School Bullying: Development and Some Important Challenges Dan Olweus Research Centre for Child and Youth Mental Health, Uni Health, Uni Research, and University of Bergen, PB 7810, Bergen NO-5020 Norway; email: [email protected]Annu. Rev. Clin. Psychol. 2013. 9:751–80 First published online as a Review in Advance on January 3, 2013 The Annual Review of Clinical Psychology is online at http://clinpsy.annualreviews.org This article’s doi: 10.1146/annurev-clinpsy-050212-185516 Copyright c 2013 by Annual Reviews. All rights reserved Keywords definition, bully, victim, cyber bullying, peer relations research Abstract After sketching how my own interest and research into bullying problems began, I address a number of potentially controversial issues related to the definition and measurement of such problems. The importance of maintain- ing the distinctions between bullying victimization and general victimization and between bullying perpetration and general aggression is strongly em- phasized. There are particular problems with the common method of peer nominations for purposes of prevalence estimation, comparisons of such es- timates and mean levels across groups and time, and measurement of change. Two large-scale projects with time series data show that several recent claims about cyber bullying made in the media and by some researchers are greatly exaggerated and lack scientific support. Recent meta-analyses of the long- term outcomes for former bullies and victims provide convincing evidence that being involved in such problems is not just a harmless and passing school problem but something that has serious adjustment and public health con- sequences that also entail great costs to society. Another section presents my view of why the theme of bullying took quite some time to reach the peer relations research community in the United States and the role of a dominant research tradition focusing on “likeability” in this account. In a final section, I summarize some reasons why it may be considered impor- tant and interesting to focus both research and intervention on bully/victim problems. 751 Annu. Rev. Clin. Psychol. 2013.9:751-780. Downloaded from www.annualreviews.org by University of Bergen UNIVERSITETSBIBLIOTEKT on 03/30/13. For personal use only.
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CP09CH27-Olweus ARI 25 February 2013 18:29
School Bullying:Development and SomeImportant ChallengesDan OlweusResearch Centre for Child and Youth Mental Health, Uni Health, Uni Research, andUniversity of Bergen, PB 7810, Bergen NO-5020 Norway; email: [email protected]
Annu. Rev. Clin. Psychol. 2013. 9:751–80
First published online as a Review in Advance onJanuary 3, 2013
The Annual Review of Clinical Psychology is online athttp://clinpsy.annualreviews.org
This article’s doi:10.1146/annurev-clinpsy-050212-185516
definition, bully, victim, cyber bullying, peer relations research
Abstract
After sketching how my own interest and research into bullying problemsbegan, I address a number of potentially controversial issues related to thedefinition and measurement of such problems. The importance of maintain-ing the distinctions between bullying victimization and general victimizationand between bullying perpetration and general aggression is strongly em-phasized. There are particular problems with the common method of peernominations for purposes of prevalence estimation, comparisons of such es-timates and mean levels across groups and time, and measurement of change.Two large-scale projects with time series data show that several recent claimsabout cyber bullying made in the media and by some researchers are greatlyexaggerated and lack scientific support. Recent meta-analyses of the long-term outcomes for former bullies and victims provide convincing evidencethat being involved in such problems is not just a harmless and passing schoolproblem but something that has serious adjustment and public health con-sequences that also entail great costs to society. Another section presentsmy view of why the theme of bullying took quite some time to reach thepeer relations research community in the United States and the role of adominant research tradition focusing on “likeability” in this account. In afinal section, I summarize some reasons why it may be considered impor-tant and interesting to focus both research and intervention on bully/victimproblems.
Research on bully/victim problems over the past 15 years or so has exploded, and there has beena parallel increase in attention from the media, schools, and relevant authorities. In my view,this has been a successful and fortunate development by and large. Like any relatively new field,however, the field of bullying research is to some extent plagued by problems, disagreements,and unresolved issues. To achieve a solid and coherent body of knowledge with well-replicatedfindings, it is important to reach some consensus on important conceptual and methodologicalissues. In this review, I take a largely critical-analytical approach and focus more on problems thanon successes. I begin by describing how my own interest and research on these problems started
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and conclude by summarizing some reasons why it may be considered important and interestingto focus both research and intervention on bully/victim problems.
A terminological note: I use the terms bullying, bully/victim problems, bullying others/beingbullied, and bullying perpetration/bullying victimization as approximate synonyms in this review.Although we try as much as possible to avoid the labels bully and victim in practical interventionwork and otherwise, they are the terms used regularly in the research literature and are also usedin the present text.
THE BEGINNINGS
A strong societal interest in the phenomenon of peer bullying first started in Sweden in the late1960s and early 1970s under the designation mobbning or “mobbing” (Heinemann, 1969, 1972;Olweus 1973a). The term was introduced into the public Swedish debate by a school physician,P.-P. Heinemann, in the context of racial discrimination (Heinemann 1969). Heinemann had“borrowed” the term mobbing from the Swedish version of a book on aggression written by thewell-known Austrian ethologist, Konrad Lorenz (1963, 1968). In ethology, the word mobbing isused to describe a collective attack by a group of animals on an animal of another species, which isusually larger and a natural enemy of the group. In Lorenz’s book (1963), mobbing was also usedto characterize the action of a school class or a group of soldiers ganging up against a deviatingindividual. Parenthetically, it was later was found out that it was not Lorenz who used the termmobbing in his German original but the Swedish translator, himself an ethologist by profession(Lagerspetz et al. 1982).
The term mob has been used for quite some time in social psychology (Lindzey 1954) andto some extent by the general public in English-speaking countries, to describe a relatively largegroup of individuals—a crowd or a mass of people—joined in a common activity or goal. Asa rule, the mob has been formed by accident, is loosely organized, and exists only for a shorttime. In the social psychological literature, distinctions have been made between several types ofmobs, including the aggressive mob (the lynch mob) and the panic-stricken mob (the flight mob).Members of the mob usually experience strong emotions, and the behavior and reactions of themob are considered to be fairly irrational (see Lindzey 1954).
At an early point in this debate, I expressed doubts about the suitability of the term mobbing,as used in ethology/social psychology, to describe the kind of peer harassment that occurred inschool settings (Olweus 1973a, 1978). Generally, with my background in aggression research (e.g.,Olweus 1969, 1973b), I felt that the connotations implied in the concept of mobbing could easilylead to inappropriate expectations about the phenomenon of bullying and to certain aspects of theproblem being overlooked.
One particular point of concern with the term mobbing related to the relative importance ofthe group versus its individual members. The notion that school mobbing is a matter of collectiveaggression by a relatively homogeneous group did in my view obscure the relative contributionsmade by individual members or small subgroups. More specifically, the role of particularly activeperpetrators or bullies could easily be lost sight of within this group framework. In this context, Ialso questioned how often the kind of all-against-one situations implied in mobbing actually occurin school. If harassment by a small group or by a single individual were the more frequent type inschools, the concept of mobbing might, for example, result in teachers having difficulty identifyingthe phenomenon of bullying in their classrooms. In addition, the concept of mobbing often seemsto place responsibility for potential problems with the recipient of the collective aggression, thevictim, who is seen as irritating or provoking the majority of ordinary students in one way oranother. This was clearly the situation in the early Swedish debate.
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Use of the concept of mobbing might also lead to an overemphasis on temporary and situa-tionally determined circumstances: “The mob, suddenly and unpredictably, seized by the mood ofthe moment, turns on a single individual, who for some reason or other has attracted the group’sirritation and hostility” (Olweus 1978, p. 5). Although I believed that such temporary emotionaloutbreaks from a group of school children could occur, I considered it more important to directattention to another kind of situation, in which an individual student is exposed to aggressionsystematically and over longer periods of time—whether from another individual, a small group,or a whole class (Olweus 1973a, 1978).
An additional problem was that, at that time, there existed basically no empirical research datato shed light on the many issues and concerns involved in the general debate about the bullyingphenomenon. Against this background, I initiated in Sweden (I am a native Swede who has livedin Norway for more than 40 years), in the early 1970s, what now appears to be the first systematicresearch project on bullying by peers. Results from this project were first published as a book inSwedish in 1973 (Olweus 1973a). In 1978, a somewhat expanded version of this book appearedin the United States under the title Aggression in the Schools: Bullies and Whipping Boys (Olweus1978). A key aim of this research was to sketch a first outline of the anatomy of peer harassment inschools and to seek empirical answers to at least some of the key questions that had been in focusin the public Swedish debate.
In retrospect, I think it is fair to say that this project and later research (e.g., Farrington1993; Olweus 1978, 1993, 1994) have shown that several of my early concerns were justified. Forexample, there is no doubt that students in a class vary markedly in their degree of aggressivenessand that these individual differences tend to be quite stable over time, often over several years,if no systematic intervention is introduced (Olweus 1977, 1979). This and similar statements inmy writings have sometimes been interpreted as if I don’t apply or appreciate a group perspectiveon bullying problems. That is a misunderstanding: A group (and larger-context) perspective onbullying problems is certainly both necessary and valuable, but so is an individual differenceperspective (see, e.g., Olweus 2001, pp. 14–17, about the bullying circle, among other things).
Similarly, the research clearly shows that a relatively small number of students in a classroomare usually much more actively engaged in the harassment or bullying than others, who are notdirectly involved in bullying at all or only in more or less marginal roles (Olweus 1993, 2001).Reports from bullied students indicate that they are most often mainly bullied by a small groupof two or three students (Olweus & Solberg 1998), often with a negative leader. In addition, aconsiderable proportion of the victims, some 25% to 35%, report that they are mainly bulliedby a single student (Olweus & Solberg 1998). Data from researchers in England, Holland, andJapan, participating in the same cross-national project on bully/victim problems, indicate thatthis is largely true also in other ethnic contexts with (partly) different cultural backgrounds andtraditions ( Junger-Tas & Kesteren 1998, Morita & Soeda 1998, Smith et al. 1999). Further, theseand other data (e.g., Rigby & Slee 1991) also show that a considerable proportion of the studentsin a class have a relatively negative attitude toward bullying and would like to do, or actually tryto do (according to self-reports), something to help the victim.
This research-based picture of peer harassment in schools is very different from what is gen-erally implied in the social psychological or ethological concepts of mobbing. Also, the use ofthe term mobbing (and derivatives of it) by Scandinavians has certainly come to deviate fromboth the scientific and the ordinary English root meaning of the term. This is particularly evidentwhen we hear a (Scandinavian) student saying “he/she mobbed me today.” Obviously, the wordmobbing has gradually, and in part on the basis of highly publicized research findings, acquired anew meaning in Scandinavian everyday language, loosely implying relatively systematic, repetitiveharassment of an individual (or possibly a group) by one or more other individuals (usually but
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not necessarily by a peer/peers). This new meaning of the word is well established in Norway,Sweden, and Denmark.
At the same time, it was clear at an early stage that, for an English-speaking audience, the termsmob and mobbing are not very useful in describing the phenomenon of bullying; they typicallyelicit associations in the direction of the social psychological/ethological concepts and the originalmeaning of the word mob. On the basis of experiences along these lines, I decided to use theterm bully/victim (or whipping boy) problems (instead of, or in addition to, mobbing) in my earlywritings in English (e.g., Olweus 1978). And most of the international attention to these problemsover the past 20 years or so concerns some variant of the term bullying and not mobbing.
At the time of initiation of my first research project on bullying, it was not possible, or evendesirable, to set forth a very stringent definition of peer harassment or bullying. However, theneed for a relatively clear and circumscribed definition became urgent in connection with thegovernment-initiated campaign against bullying in Norway in 1983 (Olweus 1986, 1993). Specif-ically, an important part of this campaign was a nationwide registration of bully/victim problemsby means of a student questionnaire that I developed. The basic definition of bullying or peervictimization underlying the construction of the questionnaire was the following: A student isbeing bullied or victimized when he or she is exposed, repeatedly and over time, to negative ac-tions on the part of one or more other students. This definition emphasized intentionally negativeor aggressive acts that are carried out repeatedly and over time. It was further specified that inbullying there is a certain imbalance of power or strength. The student who is exposed to negativeactions has difficulty defending himself or herself (for further details, see Olweus 1993, 1999a).
MEASURING BULLY/VICTIM PROBLEMS WITH THE OLWEUSBULLYING QUESTIONNAIRE
In my first research project on bullying comprising some 900 boys who were 13 to 15 years oldat the first time of measurement, I used a combination of teacher nominations and peer ratings toclassify students as victims (whipping boys), bullies, and “control boys” (Olweus 1973a, 1978). Theproject also used a number of other data sources including self-reports, mother reports, stress hor-mone data, projective techniques, and psycho-physiological measurements (e.g., Olweus 1980a,b;Olweus et al. 1988). Although a number of self-report items related to bullying and victimizationwere included in the project, they were not used in the classification of the students into the vari-ous bully/victim categories. However, extensive experience with the questionnaire I developed inthe context of Norway’s nationwide 1983 campaign against bullying and the associated interven-tion project from 1983 to 1985 (Olweus 1991, 2005) convinced me that a carefully constructedquestionnaire can be an excellent tool for the measurement of bully/victim problems.
Although the basic definition of bullying (involving the three criteria listed above) has beenretained unchanged, the “definition” presented to the students in a revised version of the question-naire, the Revised Olweus Bullying Questionnaire (OBQ) (in earlier writings, often referred to asthe Olweus Bully/Victim Questionnaire; Olweus 1996, 2007), has been somewhat expanded. Inthe latest version of the questionnaire (Olweus 2007) this (copyrighted) definition reads as follows:
We say a student is being bullied when another student, or several other students,
� say mean and hurtful things or make fun of him or her or call him or her mean and hurtful names� completely ignore or exclude him or her from their group of friends or leave him or her out of
things on purpose� hit, kick, push, shove around, or lock him or her inside a room
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� tell lies or spread false rumors about him or her or send mean notes and try to make other studentsdislike him or her
� and other hurtful things like that.
When we talk about bullying, these things happen repeatedly, and it is difficult for the student beingbullied to defend himself or herself. We also call it bullying when a student is teased repeatedly in amean and hurtful way. But we do not call it bullying when the teasing is done in a friendly and playfulway. Also, it is not bullying when two students of about the same strength or power argue or fight.
After a general or global question about being bullied in the past couple of months (or bullyingother students, in a different section of the questionnaire), taking all possible forms of bullyinginto account, the students are asked to respond to questions about nine specific forms of bullyingthey may have been exposed to. These various forms of bullying comprise direct physical andverbal (including racial and sexual) harassment and threatening and coercive behaviors, as well asmore indirect or relational ways of harassment in the form of intentional social isolation, havingrumors spread, and manipulation of friendship relationships. There are also some questions aboutdigital or cyber bullying (below).
The questionnaire can be administered in both anonymous (e.g., Olweus 2005) and confidential(e.g., Olweus 1991, Solberg & Olweus 2003) modes. To make the measuring instrument moresensitive to change, most of the questions refer to a specific, relatively short reference period,“the past couple of months.” For most of the questions, the response alternatives are frequencyalternatives, and they are made as concrete as possible: “I have not been bullied at school in thepast couple of months,” “it has only happened once or twice,” “2 or 3 times a month,” “about oncea week,” and “several times a week,” usually coded from 0 to 4. The questionnaire also containsseveral questions about the reactions of “others” to bullying, as perceived by the respondents; thatis, the behavior and attitudes of teachers, peers, and parents. These questions provide importantinformation about the school’s efforts to counteract bullying and in which areas additional effortsmay be particularly needed.
DEFINITION OF BULLYING
As defined above, bullying is a subset of aggressive behavior, which in turn is generally definedas “behavior intended to inflict injury or discomfort upon another individual” or in similar terms(Berkowitz 1993, Olweus 1973b, Tedeschi & Felson 1994). Since most bullying occurs withoutapparent provocation on the part of the targeted child or youth, it is usually considered to be a formof proactive aggression (in contrast to reactive aggression; Coie & Dodge 1998). Bullying is thusaggressive behavior with certain special characteristics such as an asymmetric power relationshipand some repetitiveness.
Use of the three criteria of intentionality, some repetitiveness, and imbalance of power forclassification of a behavior as what can be called traditional or conventional bullying seems to havebeen well accepted among both researchers and practitioners for a substantial number of years(e.g., Smith & Brain 2000, Smith et al. 2012). With the advent of cyber bullying, that is, bullying viaelectronic forms of contact (Smith et al. 2008) or communication, concerns have been raised aboutwhether and possibly how both the repetitiveness and the power imbalance criteria in the generaldefinition of traditional bullying can be applied to cyber bullying. It is obvious, for example, thatsome ways of being cyber bullied such as having been exposed to a personally embarrassing pictureor video on a website are usually single—and not repeated—acts for both target and perpetratorbut can spread quickly to a large group of people. And how should one conceive of the power
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imbalance in episodes of cyber bullying? Before addressing such questions, I want to make a fewcomments on the three basic criteria used in the general definition of (traditional) bullying.
Intentionality
As mentioned above, the concept of aggressive behavior(s) implies an intent or desire/aim toinflict harm (injury or discomfort) upon another. Some people have raised concerns about theuse of intentionality of bullying behavior as a form of aggressive behavior: How do we knowthat the perpetrator really intends to harm the other person? And following up: If this is part ofthe definition, should not the investigator/observer/researcher make sure/document that this isactually the case? The issue of intentionality has a long history of discussion among aggressionresearchers, and with regard to most behaviors that are considered aggressive the assessment ofintentionality typically does not come from asking the perpetrator about his or her intentions,for example, but rather from an analysis and understanding of the context. If it can be impliedor assumed that the perpetrator(s) knows or understands that the exerted behavior is or will beperceived as unpleasant and maybe distressing or harmful by the targeted person, such presumedawareness on the part of the perpetrator is usually enough to classify the behavior as aggressive.Such assessments are also likely to be an important part of the targeted person’s evaluation ofthe situation and the motive(s) behind the behavior. Some aggression researchers also want toadd that the behavior the target is exposed to should be “unwanted” by the target, in orderto clearly differentiate it from potentially hurtful behaviors in a sadomasochistic context. Withregard to intentionality, an exception is also made for potentially hurtful behaviors when used inthe context of a “social role” such as that of dentists or surgeons who intentionally “inflict injuryand discomfort” upon their patients but where there is typically no reason to assume an underlyingintent/desire to hurt or harm (Buss 1961).
Some Repetitiveness
A major reason why I introduced the criterion of repetitiveness was that one can then be morecertain that the negative behavior is intended. However, I never thought of this as an absolutelynecessary criterion (Olweus 1993, 1999a). In the definition of bullying presented in the OBQ,the original formulation is “When we talk about bullying, these things happen repeatedly,” butthe response alternatives also include “once or twice” (in the past couple of months). In somerecent versions of the questionnaire, including the one used in Norway, we have made a slightmodification by stating that “these things may happen repeatedly” or “are usually repeated,”depending on what is most natural with the relevant language.
Power Imbalance
The third criterion of a power imbalance favoring the perpetrator(s) is quite important and alsoclosely associated with the general issue of who is to define when bullying has occurred or occurs.In my view, the ultimate “power of definition” must reside with the targeted student—at least as abasic point of departure. Given the sometimes complex and subtle behaviors involved in bullyingand maybe a particular historical personal background for the behavior, it is often very difficultfor a “reasonable outside” person (cf. Smith et al. 2012) to assess the situation correctly. At thesame time, it is clear that a closer investigation of the situation may sometimes reveal that thingsare more complex than they appear on the surface and that perspectives from the outside may bevery helpful in finding solutions to the problematic situation. In this context, however, one must
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also be aware of the tendency of some schools (as potential judges) to portray, when confronted,even obviously abusive situations as “regular peer conflicts” between equals as a way of escapingresponsibility.
What this implies is that we are here dealing with a power imbalance as perceived by thetargeted youth. The perceived imbalance is likely to be associated with such objective factors asphysical strength or difference in numbers but may also relate to differences in self-confidence,popularity/status in the peer group, and the like. One important aspect here is very likely thetargeted student’s perception of how difficult it would be for him/her to defend him/herself ina reasonable way and maybe with some success. Another aspect is of course how the studentperceives the motives behind the behavior s/he is exposed to, whether or not it is perceived asaiming to hurt and create problems for him/her.
What About the Three Criteria as Regards Cyber Bullying?
The issue of whether and how the three key criteria of traditional bullying can be applied to cyberbullying is discussed in considerable detail in a recent chapter by Smith et al. (2012). After thought-ful consideration of a number of different aspects, the authors reach the tentative conclusion thatthe three key criteria defining traditional bullying are largely applicable to cyber bullying as well.They suggest that the imbalance of power can be assessed “in terms of differences in technologicalknow-how between perpetrator and victim, relative anonymity, social status, number of friends,or marginalized group position” (p. 36). In partial contrast to my position stated above, however,they do not think the imbalance of power should be based on the victim’s perception but ratherfrom an “outside” perspective as much as possible.
It is of vital importance for the building of a solid and cohesive body of knowledge aboutbullying that researchers can reach and use in their research a reasonably common conceptualdefinition of the phenomenon. But empirical analyses can also help inform such a development.In the following analyses, the main focus is on whether the ordinary response alternatives of theOBQ can be meaningfully used also with cyber bullying items.
The aim of these analyses was to examine if cyber bullying items (being bullied) would relatedifferently than the global traditional bullying items to a variable that these items can be expectedto correlate with (Olweus 2012a). Poor self-esteem is one variable that has been found to be linearlyrelated to the five frequency response alternatives of the global being bullied question in the OBQ(varying from “not bullied in the past couple of months” to “several times a week”; Solberg &Olweus 2003). The background for this comparison is that some forms of cyber bullying can referto single—and not repeated—events but still be shared with a large group of people and be readagain and again. Being exposed to such cyber behavior can certainly be very distressing for thetarget, and it might be considered a “misclassification” if the targeted student were categorizedas “not being cyber bullied” because the event happened only once (with the common “2 or 3times a month” as a lower-bound criterion for classifying a respondent as being bullied). If suchmisclassifications occurred for several episodes of cyber bullying, one would not expect a regularlinear increase in poor self-esteem with increasing frequency of cyber bullying but rather somedifferent pattern with an elevated level of poor self-esteem for the “once or twice” category.
This was clearly not the result of our empirical analyses, where we found a linear-increasing re-lation between the five response alternatives for the general being cyber bullied question and poorself-esteem. Students who were exposed to cyber bullying more often tended to have systematicallypoorer self-esteem. This result is very similar to what has been found in previous analyses of tradi-tional global being bullied questions. Similar results were also obtained when the relation between
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five different means or channels of being bullied—by email, instant messaging, chat room, websiteand mobile/cell phones—and poor self-esteem was examined (for details, see Olweus 2012a,b).
In this context, it is also worth pointing out that some forms of traditional bullying, for example,that of having false rumors spread, are somewhat similar to the special forms of cyber bullyingwith regard to the implicated spreading mechanisms (Smith et al. 2012, Ybarra et al. 2012). Forfalse rumors (and other traditional forms) there was also a regular linear relation between the fivefrequency categories and poor self-esteem. Applying the standard criterion of some repetition fordefining somebody as being bullied thus appears to have functioned quite well also for this formof (indirect) bullying. What these results indicate is that cyber bullying items seem to function inroughly the same way as items on traditional bullying—which could be a desirable result from theperspective of simplicity or parsimony. It must be emphasized, however, that only one “external”psychosocial adjustment variable has been used in these analyses, poor self-esteem. This variableis no doubt a meaningful and important variable for this kind of analyses, but to find out if theobtained results can be generalized more broadly, it is obviously necessary to use a larger set ofexternal variables and more channels or means of cyber bullying. There is clearly a need for moreresearch on such issues.
SOME MEASUREMENT ISSUES
Distinctions Between Bullying Victimization and General Victimization andBetween Bullying Perpetration and General Aggression
As mentioned, bullying is conceived of as a special form of aggressive behavior in the context ofa power-imbalanced relationship. From a conceptual point of view, the most important charac-teristic distinguishing bullying from generally aggressive behavior—often without an identifiedor consistent target—is no doubt the power imbalance between the perpetrator(s) and the target.We have repeatedly argued on purely conceptual grounds that not including the power imbalancein the measurement procedures in one way or another is likely to have some unfortunate con-sequences (Olweus 2010, Solberg et al. 2007). One consequence relates to the fact that studentswho themselves initiate many aggressive interactions are likely to be exposed to aggressive actsfrom their opponents also when they are clearly the winners of the aggressive interaction. Thesestudents will then correctly report that they have been exposed to aggressive acts and as a con-sequence also be included in the total group of victims (including bully-victims). However, suchstudents are likely to be partly different from students who have been exposed to the aggressive actsin the context of a bullying relationship with a clear power imbalance. To classify such aggressivestudents as victims would also increase the overlap between bullies and victims as well as the cor-relation between victimization and aggression/bullying variables in dimensional analyses, possiblyleading to largely incorrect conclusions that bullies and victims are the same students, as has beenreported in some research (see Solberg et al. 2007). Generally, the distinctions mentioned abovealso lead naturally to a separation of three groups of key actors involved in bully/victim problems,representing very different reaction patterns and personality profiles: pure bullies or bullies only,pure victims or victims only, and bully-victims (Olweus 1978, 1993; Solberg et al. 2007, 2010).
There may also be unfortunate consequences when it comes to intervention. General aggressivebehavior is sometimes interpreted as a natural and maybe healthy response to an oppressive societyor a disadvantaged situation, whereas being a victim of bullying by powerful peers constitutes aviolation of fundamental human rights (Olweus 1993). A school’s moral obligation to counteractand prevent the latter kind of malignant behavior will certainly be much more compelling than toreduce aggressive behavior in general.
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Does the Power Imbalance Make a Difference?
But does it make a difference if the power imbalance aspect is included in the empirical mea-surement procedures? In the OBQ, the power imbalance implied in bullying is introduced as aqualifying part of the general definition presented to the students (see definition above). Based onthe picture of the pure victims/victims only generated from the students’ responses (Solberg et al.2010), it is our clear impression that the students have an understanding of the difference betweenbeing exposed to aggressive behavior in a power-imbalanced relationship, that is, being bullied,and being exposed to (recurrent) aggressive acts in a fight or conflict between students of roughlyequal power or strength. However, we have not ourselves studied the problem systematically froman empirical point of view.
In a relatively recent paper, Hunter et al. (2007) took a more direct approach to the powerimbalance issue. In their study of approximately 1,400 students in the 8 to 13 years age range, theresearchers asked the participants to indicate via self-report how often they had been exposed to anumber of aggressive behaviors in the past two weeks. In addition, the participants were asked toindicate if the aggressor(s) in question was more “powerful” as reflected in greater physical strength,higher popularity, or a situation in which the perpetrator was part of a group. Victims of bullying,that is, students exposed to aggression in a power-imbalanced relationship, perceived significantlymore threat and less control over their situation in addition to being more depressed, engagingin more wishful thinking, and seeking more social support than the other group. In conclusion,the authors emphasized the importance of making a distinction between peer-victimized studentsand bullied students with the presence of a power imbalance as the differentiating criterion. Theresults of this study clearly suggest that, from the perspective of the targeted students, bullying isa more serious and hurtful form of peer aggression.
A couple of conclusions from a paper by Ybarra and colleagues (2012) are also relevant inthis context. In two different studies reported in the same article, members from an online panelwere randomized to different conditions varying the form of administration of a questionnaireon bullying and cyber bullying. An important result was that using “a behavioral list of bullyingexperiences without either a definition or the word ‘bully’ results in higher prevalence rates andlikely measures experiences beyond the definition of ‘bullying’ ” (Ybarra et al. 2012, p. 5). Theprevalence data for the various forms were also checked for possible misclassification, and a follow-up question about the power imbalance between the perpetrator(s) and the target was clearly mosteffective in reducing misclassification.
It is also interesting to note that in a meta-analysis of predictors of bullying and victimizationin childhood (Cook et al. 2010), there was a clearly significant moderator effect of “measurementapproach” (table 8, p. 76): The “bully group” was (also) characterized by internalizing problemswhen measurement was performed via behavioral descriptors of general aggression (average effectsize r = 0.17) rather than by specific reference to bullying (average effect size r = 0.02). (Sur-prisingly, however, and in conflict with these results, the discussion section in the paper concludesthat “effect sizes were not influenced by measurement approach,” Cook et al. 2010, p. 78.) Thesemoderator results are consistent with the arguments presented above about the increased overlapbetween bullies and victims when bullying is measured with general aggression items and withoutits defining criteria.
Generally, although there is a need for more empirical research on these issues, conceptualarguments and the reported empirical findings so far clearly support the usefulness of a distinctionbetween a bullying perpetration/bullying victimization research line on the one hand and a generalaggression/general victimization line on the other (also see an early identification of this distinctionin Schafer et al. 2002). Victims of bullying are likely to overlap in part with and can be seen as
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a subgroup of peer-victimized students with special characteristics. Similarly, students who bullyothers are likely to overlap in part with and can be seen as a subgroup of aggressive students withspecial characteristics. Although there is a good deal of overlap between the subgroups, they aredefinitely not identical. At this point in time, it is essential to be clear about these likely differences,to be more correct and precise in describing and interpreting the results of empirical studies, andnot to use the relevant terms as synonymous without empirical support. With regard to the latterpoint, authors should be careful not to present results as applying to bullying when they actuallyhave measured general victimization and general aggression (also see Hunter et al. 2007). A specialcase in point is when the results from studies based on questionnaires designed to measure generalaggression are reported as being research on bullying or bully/victim problems. Such practiceswill only create confusion and prevent building of a cohesive and consistent knowledge base.
SOME MEASUREMENT ISSUES RELATED TO THE OLWEUSBULLYING QUESTIONNAIRE
Reliability
According to Cornell & Bandyopadhyay (2010), the OBQ “is the most important and widely usedbullying survey worldwide, yet there is little published information about its reliability and valid-ity.” Although issues of the reliability and validity of the OBQ have certainly not been neglectedor understudied by me and my colleagues, the comment about the lack of published informationhas some merit. Accordingly, it is appropriate to briefly report about relatively recent studies withsuch information.
With regard to the reliability of the bullying perpetration and bullying victimization scalesof the eight or nine various forms of bullying included in the OBQ, there are now availableseven empirical studies with such information from independent researchers from several differentcountries (Fekkes et al. 2005, Felix & McMahon 2006, Ferguson et al. 2009, Hartung et al.2011, Jenson et al. 2010, Kyriakides et al. 2006, Stavrinides et al. 2010, Strohmeier et al. 2011,Theriot et al. 2005). Results have been reported in the form of internal consistency coefficients likeCronbach’s alpha or item response theory (IRT) technology and have been uniformly quite goodwith reliabilities in the 0.80–0.90 range. Similar findings are obtained in our own IRT analysesfor the bullying others scale based on a very large sample of Norwegian students (n = 48,926;Breivik & Olweus 2012).
As reported in Solberg & Olweus (2003), the correlation between school-level prevalenceestimates based on the dichotomized global being bullied and similar estimates based on the (inthis study, seven) specific forms of being bullied was quite high, r = 0.79. The correspondingcorrelation for school-level prevalence estimates based on the dichotomized global and specificbullying others items, respectively, was 0.77. After application of the Spearman-Brown formula(Guilford 1956) to estimate the school-level reliability of the combined prevalence estimates, thesecorrelations approached 0.90, indicating that such estimates did an excellent job in differentiatingthe schools from one another. These results have now been largely replicated in the recent FinnishKiVa project (Karna et al. 2011a). The results also attest to the usefulness of reporting prevalencedata based on the dichotomized (in contrast to continuous) global being bullied and bullying othersitems to the schools. As is well known, the use of dichotomized variables may imply some lossof information, but the choice of dichotomized versions for prevalence estimation (percentages)has been largely dictated by considerations of the need to give the schools feedback that is easy tounderstand and helpful in the planning of their intervention work (Solberg & Olweus 2003).
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Convergent Validity
There has been no systematic review of studies that have used both the OBQ and some formof peer nominations. However, in an unpublished meta-analysis presented at the Society for Re-search on Child Development symposium in Tampa, Florida in 2003, Card (2003) reported on21 studies of the correlation between self- and peer reports of victimization. Several of the studiesincluded had used the OBQ. The peer reports were both nominations and ratings. The aver-age correlation across the 21 studies was 0.37. Considering the fact that the studies included inthe meta-analysis were of varying quality and several of them were not particularly designedto maximize correspondence between data from the two sources, this is a quite respectableresult.
In the Finnish KiVa project (Karna et al. 2011a), data were obtained both with the OBQ andpeer ratings (n.b. not nominations) about physical, verbal, and indirect bullying victimizationand similar variables about participation in bullying perpetration (Salmivalli et al. 1996). Forthe OBQ, both the global being bullied/bullying others items and a scale of seven differentitems reflecting the various forms of bullying were used in the analyses. The three peer ratingswere averaged into two summary scores, with a reliability of 0.84 for being bullied and 0.90 forparticipation in bullying. The correlations between the global item and the scale of being bulliedversus the peer ratings of bullying victimization were 0.39 and 0.40, respectively. Correspondingcorrelations for the global bullying others item and the scale of bullying with the relevant peerratings were 0.36 and 0.34. It is interesting to note that the results for the single global itemsof the OBQ had equally strong correlations with the peer ratings as the scales representing thevarious forms of bullying (cf. Fuchs & Diamantopoulus 2009). These results were obtained onvery large samples of students in grades 3–12 (n = 19,780) before implementation of the KiVaintervention program (C. Salmivalli, personal communication). With correction for unreliability(attenuation correction), the convergent validity correlations would be even higher (Guilford1956).
These results are in stark contrast to the results obtained in some studies conducted by Cornelland his associates (Branson & Cornell 2009, Cornell 2010, Cornell & Brockenbrough 2004, Lee& Cornell 2010), where the correspondence between self-reports and standard peer nominationsof victim and bully status have been much lower, in the 0.10–0.20 range in some cases. Theremay be several reasons for this discrepancy, but in the most directly relevant of these studies,with the title “Concurrent Validity of the Olweus Bully/Victim Questionnaire” (Lee & Cornell2010), the sample used was exceptionally small considering its purpose, only 202 students. Thevery small sample size resulted in the self-identification of only two bullying students when thestandard criterion of “2 or 3 times a month” (Solberg & Olweus 2003) was applied. There wereslightly more self-reported victims (n = 13), and for being bullied, the correlation with peernominations was actually, and somewhat surprisingly, as high as 0.42, much in line with theresults just reported. In addition, as also acknowledged by the authors of all cited papers, theschools included in the research studies were all in the process of using the Olweus BullyingPrevention Program (OBPP), which may have compounded the assessment situation further.Under such conditions, strong claims about the inadequacy or lack of validity of the OBQ orself-reports about bullying and victimization in general cannot be taken quite seriously.
Summing up, the correlations in the Card meta-analysis and the KiVa project were in the 0.35–0.40 range, maybe with somewhat lower values for bullying perpetration. This result is clearlyhigher than the average association between self-reports and peer data described in a well-knownmeta-analysis of cross-informant reports on child behavior problems (r = 0.26; Achenbach et al.1987), for example.
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FACTORS CONTRIBUTING TO LACK OF CORRESPONDENCE ANDPROBLEMS WITH PEER NOMINATIONS
Although the reported results indicate that the correspondence between self-reports aboutbully/victim status with the OBQ and peer ratings/nominations concerning similar dimensionscan be considered rather satisfactory, the overlap is of course far from perfect. And there aregood grounds for not expecting such an overlap. Some of these reasons are considered in the nextsections, in which I have deliberately chosen to focus mainly on problems with peer nominations.The reason for this particular focus is that peer nominations is a very popular method, inparticular in the United States, for collecting information about peer relations including bullyingand that the methodological problems associated with its use for several purposes have receivedlittle research attention.
In a typical peer nomination procedure, students are presented with a roster of the names(and possibly pictures) of their classmates and asked to nominate a fixed number, often three,or an unlimited number of usually same-gender peers in their classroom or grade who fit oneor several descriptions of victimization/being bullied and aggression/bullying other students(Who is the kid who. . . ; He/she is picked on. . . ; Find the names of three classmates who. . .).The number or usually some percentage of nominations received is used as the student’s scoreon the relevant dimension. The scores are often standardized within gender, grade, and/orclassroom.
One likely reason for discrepancies between self-reports and peer nominations is the fact thata good deal of bullying is of a subtle and somewhat secretive nature that may be difficult for peersto observe but is clearly perceived by the targeted student and, accordingly, likely to be reportedin the OBQ.
Second, in the OBQ the students report on the frequency with which they have been bul-lied/bullied other students, whereas the peer nomination method measures frequency of nomina-tions of “extreme students,” not the frequency or seriousness of the implicated behaviors. It maybe reasonable to assume that a high proportion of the nominations that more extreme individualsare likely to receive actually reflects some frequency/seriousness (and maybe degree of visibility)dimension, at least roughly. However, for less extreme individuals, it is by no means evident thatan average number of nominations, for example, directly translates into an average level or fre-quency/seriousness of problem behaviors. Also, in most peer nomination studies a considerableproportion of students receive no nominations at all (e.g., Espelage et al. 2003), and individu-als with zero scores cannot without further analyses be assumed to have identical low levels ofthe characteristic in question. In addition, it can be shown that the variance and distribution ofnominations for a classroom (or grade) are substantially influenced by the number of nominators(classroom size) and the degree of internominator agreement. As a consequence, behaviorally fairlynonextreme students also may well be selected into the extreme group (for example, students witha standard score +1 above the mean) from relatively smaller classrooms and/or classrooms withpoor internominator agreement (typically with smaller variance). The effects of such mechanisms,which are not well described and understood, are also likely to reduce correspondence with self-report data. In this context, it should be emphasized that peer ratings in which all students in theclassroom or other relevant group usually are being assessed escape several of the problems withnominations mentioned in this paragraph.
Third, as has been documented in our studies (Olweus 1993, 1999b), a good deal of bullying iscarried out by older students toward younger ones. To be bullied by older students will be capturedin the key questions in the OBQ but is less likely to be registered in the peer nominations, whichtypically only refer to students in the nominators’ own classroom or grade.
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Fourth, as has also been documented in our studies (Olweus 1993, 1999b), a good deal of bulliedgirls report that they are mainly bullied by boys. Such cross-gender bullying will be captured inthe key questions in the OBQ but probably not in peer nominations that are often restricted tosame-gender nominees. In particular, girls bullied by boys and boys bullying girls may not be wellidentified under peer nomination conditions.
Fifth, the common practice of statistically standardizing peer nominations within class-room, gender, and/or grade will often result in the removal of meaningful between-classroom/gender/grade variance. To illustrate, if there is a marked difference in the number/proportionof nominations of bullying (extreme) students for grade 4 and grade 5 and these data are stan-dardized within grade, this means that this developmental difference is effectively eliminated.The two distributions of standardized nominations will have the same mean values and standarddeviations in spite of the fact that one grade has a much higher level of problems with bul-lying. As a related consequence, the most extreme students in each grade will receive roughlysimilar standardized values even if the extreme students in the most aggressive grade have re-ceived larger numbers/higher proportions of nominations. Since such differences in the level ofproblems are likely to be captured in self-reports, the practice of standardizing also may reducethe degree of correspondence between self- and peer reports. Results similar to those achievedthrough statistical standardization are likely to be obtained by procedurally restricting nomina-tions to students of the same category (classroom/gender/grade) in combination with use of afixed number of nominations (e.g., Find the three same-gender peers in the class who fit thedescription. . .”).
In sum, there is actually a good deal of overlap between data from self-reports and peer nom-inations as evidenced by correlations in the 0.35 to 0.40 range. As a more detailed examinationreveals, however, there are also clear differences in what the two methods are likely to measure andin how the raw data are used or “transformed” to generate the variables of interest. According tothe analysis presented here, most of the reasons for the discrepancies are linked to characteristics ofthe peer nomination method. Nonetheless, with an acceptable level of internominator agreementand a large enough group of nominators, peer nominations may provide reasonably adequate mea-sures of relatively stable, individual-differentiating bully/victim characteristics, at least as regardsmore visible or “public” forms of bullying and the more extreme individuals in the peer group.Generally, it is likely that the possible strength of the typical peer nomination method lies morein the identification of distinct extreme groups than in creating distributions of students roughlyarranged/ranked according to frequency or seriousness on the problematic behavior dimensions.The latter fact is also the reason why peer nomination data are not well suited for prevalenceestimation and for comparisons of prevalence estimates or mean levels across groups and timepoints (for details, see Olweus 2010, pp. 20–21). Against this background, it is obvious that peernomination data cannot be considered some kind of gold standard or ultimate criterion of thevalidity of self-reports on bully/victim problems.
One final point about the limitations of the peer nomination methodology concerns the mea-surement of change. Both peer nominations and self-report instruments such as the OBQ havebeen used for the measurement of possible effects of antibullying interventions, that is, to measurechange. How do these two methods compare in that regard?
Unfortunately, the very nature of the peer nomination procedure will tend to discount possiblechanges in the level of problems over time. Even if the overall level of problems has decreasedsubstantially in a school after an intervention, many bullying students nominated one year ormaybe six months earlier will most likely be nominated again as bullying other students. Thisis simply because they still are the students who fit the descriptions best even if most of themhave considerably reduced their bullying behavior at follow-up. The same will probably apply to
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students who have been bullied. The effects of such mechanisms are likely to be accentuated if thestudents are given instructions to nominate a fixed number of peers, which will tend to serve asa kind of standardization within classroom/grade/time point and will largely reduce or eliminatepossibilities for registering change.
Another important difference is that in the questions of the OBQ, for example, it is repeatedlyemphasized that the responses concern “the past couple of months.” The absence of such a refer-ence period in most peer nomination methods reinforces the focus on stable or typical behaviorpatterns or situations rather than change.
In contrast, the self-report questionnaire measures mostly painful subjective experiences ofbeing bullied, and if clear changes occur in the levels of bullying, this is likely to be quicklyregistered by the targeted student. Similarly, students who bully other students will tend to noteif their behavior is questioned, blocked, or confronted by teachers or peers, and maybe reportedto parents.
Generally, it seems that the value of peer nominations has been exaggerated and the problemsassociated with the methodology correspondingly underrated. There is simply a strong need formuch more methodological groundwork to find out if at all, and in which cases how, commonpeer nomination methods can be meaningfully used for prevalence estimation and the studyof developmental changes including comparisons of prevalence estimates or mean values acrossgroups and time.
In drawing these conclusions, I have disregarded the possible ethical problems associated withthe use of peer nominations for socially undesirable behavior patterns including “like-least nomi-nations.” In several countries, including the Scandinavian countries and Australia, many researchprojects with such peer nominations very likely would be rejected for ethical reasons by the researchevaluation committees.
ISSUES RELATED TO CYBER BULLYING
Over the past five or six years, newspapers, the popular press, and the research community, as wellas educators and parents, have paid a good deal of concerned attention to a relatively new form ofbullying among school children and youth, usually named cyber bullying or electronic bullying.As suggested in a previous section, cyber bullying is broadly defined as bullying performed viaelectronic forms of contact or communication such as mobile/cell phones or the Internet. Thegeneral picture created in the media—and often also by researchers and authors of books on cyberbullying—is that cyber bullying is very frequent, that it has increased dramatically over time, andthat this new form of bullying has created many new victims and bullies in addition to the victimsand bullies involved in traditional bullying. In addition, it is often argued or implied that cyberbullying is very difficult for adults to discover and counteract, creating a feeling of powerlessnessin adults and maybe students as well.
In the following sections, I argue that claims about cyber bullying made in the media andelsewhere are often greatly exaggerated and that several such claims have very little scientific sup-port. My arguments are based on empirical analyses of several large-scale studies, two of whichhave cross-sectional or school-level longitudinal data concerning time trends in the United Statesand Norway, respectively, at four and five time points (for more details, see Olweus 2012a,b).Furthermore, I report some analyses about the possible effects of being exposed to cyber bul-lying. Finally, I also present some thoughts on how to counteract cyber bullying and suggeststeps a school or community can take to further reduce and prevent cyber bullying among theirstudents.
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17.2
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Figure 1US time series data for 2007–2010 for verbal bullying (being bullied) and cyber bullying (being bulliedelectronically). Data from all over the United States. Total n = 447,000.
Claims About Prevalence and Time Trends
The first two major media and, in part, researcher claims to be scrutinized assert that cyberbullying is a very frequent phenomenon among today’s children and youth and that the frequencyor prevalence of the phenomenon has increased dramatically in recent years.
One of the obvious reasons why some researchers (several of whom seem to come from fieldsother than psychology) have reported high or very high prevalence figures of cyber bullying is thatcyber bullying has been studied “in isolation,” that is, outside a general context of (traditional)bullying and often also without a general student-friendly definition of what is meant by bullying.To put cyber bullying in proper perspective, it is in my view necessary to study it in the contextof (traditional) bullying more generally. As implied in previous sections of this review, one cannottalk about a phenomenon as bullying unless a reasonably precise definition has been provided tothe respondents or the formulation of the questions or other measures used make it quite clearthat the contents conform to what is usually implied in bullying.
The results that are obtained when cyber bullying is studied in the broader context of otherforms of bullying (as with the Olweus Bullying Questionnaire) are shown in Figures 1 and 2.Figure 1 illustrates the results for a very large US sample (with approximately 440,000 students) forbeing exposed to direct verbal bullying and to cyber bullying, respectively, for the four consecutiveyears between 2007 and 2010. The average across-time prevalence for being verbally bullied is17.6, and the corresponding figure for being cyber bullied is 4.5%. The average for bullying othersverbally is 9.6%, whereas the corresponding figure for cyber bullying others is 2.8% (Figure 2).
The Norwegian data with prevalence figures from 41 schools over a five-year period from2006 to 2010 show a very similar pattern of results but at somewhat lower prevalence levels(Olweus 2012a).
With regard to the second claim concerning the presumably dramatic increase of cyber bul-lying over time, both figures (as well as the Norwegian data) show that basically no systematicchange in prevalence has occurred over the time periods studied. This is true of both being cyberbullied and cyber bullying others as well as of being bullied and bullying others with direct verbalmeans.
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Stud
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Figure 2US time series data for 2007–2010 for verbal bullying (other students) and cyber bullying (other students).Data from all over the United States. Total n = 440,000.
As documented here, cyber bullying is actually a quite low-prevalent phenomenon, representingonly some 25% to 35% of the level of traditional bullying with direct verbal means. It is obviousthat the “psychological threshold” for endorsing the global items on cyber bullying is much higherthan for direct verbal bullying (Breivik & Olweus 2012). The two global questions about cyberbullying are actually among the various bullying items/forms with the lowest prevalence rates.There is no doubt that many more children and youth are involved in traditional verbal bullyingthan in cyber bullying.
Similarly, and in spite of increasing accessibility and use of mobile phones and computers, therewere no indications of increases in prevalence of cyber bullying over time, both as regards beingbullied and bullying other students. The same was true of direct verbal bullying.
Degree of Overlap of Traditional Bullying with Cyber Bullying
A third common claim made by the media and some researchers alike is that the new form of cyberbullying has created many new victims and perpetrators of bullying. This claim is based on anassumption and maybe some empirical data to suggest that children and youth who are involvedin cyber bullying are to a considerable degree different from those engaged in traditional bullying.
When this claim was checked empirically (Olweus 2012a), the results documented a very highdegree of overlap: Of students who had been exposed to cyber bullying in the US sample, 88%had been bullied in at least one traditional way. For cyber bullying others, the overlap also was88%. The results for the Norwegian schools were similar, with degree of overlap being 93% and91%, respectively.
In these analyses, there was thus only a very small percentage, about 10% of the participants,who had only been cyber bullied or had only cyber bullied others. These results suggest that thenew electronic media have actually created few new victims and bullies. To be cyber bullied orto cyber bully other students seems to a large extent to be part of a general pattern of bullying,where use of the electronic media is only one possible form and, in addition, is a form with a quitelow prevalence.
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These results also suggest that even if most cyber bullying actually occurs outside schoolhours, as has been documented in several other surveys, many—very likely, most—episodes ofcyber bullying originate in the school setting.
Are There Negative Effects of Cyber Bullying, and How Do We Find Out?
There have been many reports in the research literature and the media about the negative ef-fects of being exposed to cyber victimization—but they usually do not take into account possiblyconcurrent bullying victimization in “traditional” ways. Since a majority or maybe most cyber-bullied children are also exposed to traditional bullying, as discussed in the previous section, it isdifficult to know if, and to what extent, the reported negative effects actually are a consequenceof cyber bullying, over and above the well-documented negative effects of traditional bullying. Inthe article referred to (Olweus 2012a), I presented two sets of analyses with poor self-esteem asthe outcome variable and concluded tentatively that the issue of possible negative effects of beingcyber bullied may be context specific: If a student was bullied only (or mainly) via electronic means(which was the case for a small group of subjects), this seemed to have a negative effect on hisor her psychosocial adjustment or well-being. If the student was exposed to both traditional (tosome non-negligible degree) and cyber bullying, however, the additional effect of cyber bullyingseemed to be trivial. To find out about the possible negative effects of cyber victimization is acomplex and challenging research task, and my conclusion above should certainly be consideredpreliminary and tentative.
Unfortunate Consequences of the Distorted Media Picture
Getting back to the media picture, I want to briefly touch on two likely unfortunate consequences.First, such a distorted portrayal of reality will probably generate a lot of unnecessary anxietyand tension among parents and maybe teachers and students. It may also create feelings of pow-erlessness and helplessness in the face of the presumably “huge” and ubiquitous cyber bullyingproblem.
Second, such a picture is likely to result in an unfortunate shift in the focus of antibullyingwork if digital bullying is seen as the key bullying problem in the schools. This would probablyalso result in funneling a lot of resources in a wrong direction while traditional bullying—whichis clearly the most prevalent and most serious problem—would be correspondingly downgraded.
But should the results and conclusions be interpreted to mean that we should just disregard andstop bothering about cyber bullying among children and youth? No, this would not be a helpful lineof action. Since both intuition and some empirical research asking about the perceived impact ofhypothetical cyber bullying exposures (Smith et al. 2008) clearly suggest that some forms of bully-ing such as posting painful or embarrassing pictures or videos may have markedly negative effects,it is important also to take cyber bullying seriously both in research and intervention/prevention.It has not been my intention to trivialize or downplay cyber bullying, but I definitely think it isnecessary and beneficial to place cyber bullying in proper context (with traditional bullying) andto have a more realistic picture of its prevalence and nature.
How Can We Counteract and Prevent Cyber Bullying?
Very briefly, technologically oriented researchers and many book authors tend to emphasize theimportance of teaching students, parents, and educators various aspects of “netiquette” concerningsuch things as Internet safety, how the different technologies function, and how to behave properly
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on the Internet. It is probably useful for most students, parents, and educators today to achievea certain level of such basic knowledge about the new technologies. And many schools couldcertainly benefit from introducing and strictly enforcing clear rules about the use of cell phonesand computers or the Internet in the schools. At the same time, there seem to be basic limitationsto what can be achieved with such a technological approach, according to a recent small-scalemeta-analysis (Mishna et al. 2011).
Given that traditional bullying is much more prevalent than cyber bullying and that the greatmajority of cyber-bullied students are also bullied in traditional ways, it is natural to recommendschools to direct most of their efforts to counteracting traditional bullying, preferably using aprogram with documented effects (cf. Ttofi & Farrington 2009). In some of our own large-scaleintervention studies with relatively few measures focusing directly on cyber bullying (Olweus &Limber 2010), we have observed that levels of cyber bullying have gone down substantially in par-allel with reductions in traditional bullying. Such effects have also been convincingly documentedin a recent paper from the Finnish KiVa project (Salmivalli & Poyhonen 2011). The authorsconclude that “reducing cyber bullying does not necessarily require programs tailored to targetespecially these specific forms of bullying” (p. 68).
Such a conclusion is certainly in line with the general thrust of the arguments presented above.At the same time, I think we should also make use of the possibility that attention to cyber bullyingcases can lead to a disclosure of what actually goes on in terms of traditional bullying in the schoolcontext. In addition, the great focus on cyber bullying in the media and research can probably beused to revitalize societal interest in the phenomenon of school bullying more generally and theneed to systematically address this pressing social problem.
A System-Level Proposal
Technological experts tell us that in most cases, it is quite possible, although maybe somewhat timeconsuming, to disclose the sender(s) of negative bullying messages communicated via electronicmeans. Accordingly, I have proposed that an important and presumably quite effective measurean individual school or community can take in counteracting and preventing cyber bullying isto invest time and technical competence in disclosing thoroughly a few identified cases of cyberbullying—and then communicate clearly and openly (but anonymously) the results to the students.This system-level strategy will probably substantially increase the perceived risk of disclosure andvery likely be able to reduce further the already low prevalence of cyber bullying.
THE LONG-TERM OUTCOMES FOR BULLIES
Although myriads of studies have been conducted on the concurrent characteristics of bullies,victims, and bully-victims (see, e.g., Arseneault et al. 2010, Jimerson et al. 2010 for overviews),much less research has examined the long-term outcomes for these groups based on prospectivestudies. An early such study, often referred to as the first of its kind, was my study of threeconsecutive community cohorts of boys from Greater Stockholm (n = 780) who had participatedin my first research project on bullying when they were in grades seven to ten (Olweus 1978,1991, 1993, 2010). When the criminal records of these boys were followed-up in the officialSwedish crime registers up to age 24, it was found that the former school bullies, as assessed by acombination of teacher nominations and peer ratings, were heavily overrepresented. Nearly 55%of the school bullies had at least one conviction (any kind of crime resulting in conviction) in theperiod from age 16 to 24 years, and 36% had three or more convictions, whereas only 9.8% ofthe students who had not been involved in bullying others had as many convictions. The odds
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ratio (OR) for the latter variable was 5.12. Thus, as young adults, the former school bullies hadan almost fourfold increase in the level of serious, recidivist criminality, as documented in officialregisters. For violent crimes, the results were even more marked, with 11% of former bullieshaving two or more convictions in comparison with 1.6% of the nonbullies, the OR being 7.79.
Recently, a group of researchers from the Institute of Criminology at Cambridge University(Ttofi et al. 2011a) has conducted a meta-analysis of all prospective studies they have found on therelation between bullying perpetration and later criminal and antisocial behavior, including theSwedish study. They were able to identify 18 studies with an average follow-up time of 5.4 years(varying between 0.5 and 11 years). The average age at which bullying perpetration was measuredwas 11 years (varying between 6 and 16 years). The summary effect size was OR 2.60 (CI: 2.15–3.14; z = 9.90). When controlling for a considerable number of early covariates (seven on theaverage), the adjusted summary effect size was reduced to OR = 1.82, but this was still a highlysignificant effect (CI: 1.55–2.13). Most of the studies were based on male participants, but femaleswere included in a few of them (e.g., Renda et al. 2011). Results for females were also significantand in the same direction as for males, but effects were usually weaker. Interestingly, and relatedto the previous section on the validity of self-reports, several of the studies had assessed bullyingperpetration with some version of the OBQ (e.g., Kim et al. 2011, Losel & Bender 2011). Theauthors concluded generally that school bullying is “a strong and specific risk factor for lateroffending” (Ttofi et al. 2011a, p. 81).
In a few studies, bully status had actually been determined on the basis of a single self-reportitem (Renda et al. 2011) or a single item from the Child Behavior Checklist ( Jiang et al. 2011). Thissuggests that the findings reported in the meta-analysis very likely represent a conservative estimateof the predictive power of school bullying variables. This conclusion is further reinforced by thefact that several of the covariates (early aggressive behavior, for example) might be better regardedas a natural part of a bullying perpetration pattern than as possible confounds to be controlled. Inthis way, the covariate adjustment will thus likely represent a certain degree of overcontrol.
THE LONG-TERM OUTCOME FOR VICTIMS
The same group of researchers has conducted a similar meta-analysis of the relation between bul-lying victimization and depression (depressive states or symptoms) later in life (Ttofi et al. 2011b).In this case, 29 different studies were identified, and the summary effect size OR was 2.06 (CI:1.79–2.38; z = 9.23). The average age at which bullying victimization was measured was 12 years(varying between 8 and 18 years), and the average length of the follow-up period was 6.9 years(varying between 1 and 36 years). With control for a number of early covariates (six on average), thesummary effect size was reduced to OR = 1.74, but this was still highly significant (CI: 1.54–1.97;z = 8.77). Effect sizes were of similar magnitude for males and females. As with the meta-analysisfor bullying perpetration, the reported results are likely to be conservative estimates due to possibleovercontrol and limited reliability of some assessments of bullying victimization status.
These important meta-analyses show convincingly that being involved in such problems as abully or a victim with some regularity is not just a harmless and passing school problem. Rather,they document that such involvement is likely to result in serious long-term consequences andadjustment problems for both groups, but of a different nature: Depression and other internalizingproblems for the victims and criminality/antisocial behavior and other externalizing problems forthe bullies. As emphasized in a previous section, being bullied by peers also represents a seriousviolation of the fundamental rights of the child or youth exposed (Olweus 1993, p. 48).
In addition to resulting in substantial personal suffering and difficulties for partners and family,these problems entail huge costs for society. It has been documented that both former bullies and
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victims are “overconsumers” of society’s health and social support systems (Sourander et al. 2007).Due to long sick leaves, unemployment, and early pensioning, revenues from taxation of thesegroups will also tend to be greatly reduced. All of these likely outcomes underscore the necessityand value of counteracting and preventing these problems, not only for the sake of the victims,which is the main motivation behind interventions, but also for the sake of the bullies.
Two Swedish economists have estimated that the costs to society of a “marginalized life” (up toage 65) amount to approximately two million US dollars (Nilsson & Wadeskog 2008). Althoughthe calculations are not directly based on the lives of bullies and victims, the estimates are likelyto be roughly applicable also to a considerable proportion of such individuals. The economistsconclude (in translation): “. . .in order for an (intervention) project to be economically profitablefor society, the success rate need only be 1.5 percent” (Nilsson & Wadeskog 2008, p. 10).
EFFECTIVENESS OF ANTIBULLYING PROGRAMS
A few years ago, the Cambridge group also conducted a meta-analysis of the effectiveness of allantibullying programs in the world (Ttofi & Farrington 2009, 2011). They were able to locate 59reports representing 30 programs with scientific evaluations of reasonable quality. As a generalconclusion, the authors stated that antibullying programs are effective in reducing bullyingand victimization by 20% to 23% in intervention schools as compared with control conditions(Ttofi & Farrington 2009). Although this meta-analysis no doubt is the most comprehensive andthorough of its kind available, the considerable variation in results among programs makes onewonder if a general statement about the expectable effect of “any antibullying program” (froma potential population of programs) is defensible. A closer look at the results suggests that thechances that some programs would result in positive effects seem very small. It should also beremembered that all programs in the meta-analysis except one (the OBPP, the Olweus BullyingPrevention Program with five replications) were efficacy, first-time (nonreplicated) studies, oftenwith extra resources and support from the researchers conducting the study the result is basedon (Flay et al. 2005; also cf. the article “The desperate need for replications”, Hunter 2001).Nonetheless, the overall results of this careful meta-analysis are clearly positive and indicatethat at least some theory-guided, research-based antibullying programs very likely will leadto considerable reductions in bully/victim problems (such as the OBPP as emphasized by theauthors; Ttofi & Farrington 2009, pp. 20, 23). Although not studied directly in the meta-analysis,programs are presumably particularly likely to be successful if they are combined with a goodimplementation model and if implementation of the program is made with some degree of fidelity.
After publication of the meta-analysis just described, there are at least two additionallarge-scale intervention projects that merit attention: the Finnish KiVa project, where positiveresults have already been published (Karna et al. 2011a,b), and a three-year intervention projectwith the OBPP in Pennsylvania, where encouraging results are in the process of being analyzed(Limber & Olweus 2013).
WHY BULLY/VICTIM PROBLEMS CAME LATE INTHE UNITED STATES
In the following section of the present review, I take up again the thread from the beginningconcerning the development of the field of bullying research, with a special focus on what happenedand did not happen in the United States.
For quite some time after publication of my first study (Olweus 1973a, 1978), I worked relativelyalone on research about and intervention work against bully/victim problems at an internationallevel. However, in the early 1980s, the Finnish researcher Kirsti Lagerspetz, who before that time
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had mainly conducted research on aggression in animals, together with her associates publisheda couple of studies on school bullying (Bjorkqvist et al. 1982, Lagerspetz et al. 1982). Later on,in the late 1980s, I was visited in Bergen, maybe a year apart, by two other senior researchers,Peter Smith from the United Kingdom and Kenneth Rigby from Australia, who were interestedin doing research and also intervention work on bullying problems. Both of them became quicklyinvolved in such research and have continued to be productive and important contributors to thefield, as I believe is well known (e.g., Rigby 1996, Smith & Sharp 1994). Criminologist DavidFarrington from the United Kingdom was also an important early contributor who saw the valueand importance of studying these problems (Farrington 1993).
With regard to the development in the United States, David Perry was probably the firstresearcher to show a serious interest in the problem. But his first article with colleagues (Perryet al. 1988) was titled “Victims of peer aggression,” and Perry made it clear in his writings that hedid not directly study bullying as usually defined, but rather the not fully overlapping phenomenonof children and youth being regularly exposed to aggressive behavior from their peers (see previoussection on power imbalance).
At the time the article by Perry et al. was written, the dominant North American approach to thestudy of peer relations was to measure peer acceptance/likeability or status through positive (“likemost”) and negative (“like least”) sociometric peer nominations (as briefly described in a previoussection). Using a special classification scheme developed by Coie et al. (1982), researchers sortedtheir subjects into peer status groups of popular, controversial, neglected, rejected, and averagechildren. A special interest focused on low peer status or rejection, and it was generally believed,partly on the basis of research, that aggressive behavior on the part of the child or youth was the keydeterminant of rejected status. Much of the research from the 1980s and earlier was summarizedin an edited volume on peer rejection that was published in 1990 (Asher & Coie 1990) and in acomprehensive meta-analysis conducted by Newcomb et al. (1993).
Research on bullying in the United States did not become frequent or perceived as importantuntil the early part of the first decade of the twenty-first century, more than ten years laterthan in Europe (outside Scandinavia) and Australia. Given the great volume of US peer relationsresearch, this was somewhat surprising. It is my belief the this slow entry into the US peer relationsresearch community was to a considerable degree related to and actually a partial consequenceof the very strong position of the traditional North American research approach focusing onlikeability/acceptance as sketched above. My explication of the reasons for the slow developmentin the United States, in spite of many excellent peer relations researchers, may of course beperceived as provocative by some people, and I will therefore use some space to try and brieflyexplain the background and basis for my position.
My own disappointment with this general approach increased gradually during the latterhalf of the 1980s, and in 1989—at a well-attended Society for Research on Child Developmentsymposium in Kansas City—I expressed my major concerns and criticisms of the dominantapproach (Olweus 1989, 2001).
My key arguments related to the fact that peer rejection/likeability measures do not focusdirectly on the behavioral or personality characteristics of the rejected child. They rather reflectthe social environment’s (i.e., the peers’) evaluation of the child in the form of a general likingor disliking. Since children may be disliked or liked by their peers for very different reasons, itwas reasonable to expect considerable heterogeneity among children or youth who were rejectedby their peers. In contrast to the then dominant view that rejection was mainly a consequence ofaggression, children and youth in my own research (for example, Olweus 1978), who were bulliedby their peers and highly rejected, typically showed a very different pattern of behavior, one ofwithdrawal and anxiety and very little aggression.
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In addition, my data on boys who bullied other students did not support the view that aggressivebehavior typically or mostly leads to rejection by peers. Overall, the generally aggressive bullieswere relatively popular among both boys and girls, and they were often supported by two or threeother boys in the classroom (Olweus 1978).
In summary, in my symposium contribution, I argued that the presumably marked hetero-geneity of rejected children—with several more or less distinct subgroups of such children withvery different personality profiles and behavioral characteristics—and the nature of the rejec-tion/likeability variable would lead to problems of prediction, intervention, and understanding(see details in Olweus 2001). Instead, I argued for a stronger and direct focus on the behavioralor personality characteristics of the children or youth in their classroom contexts and, in parallel,on specific reactions on the part of the social environment.
Not long before the symposium mentioned above, and unknown to me, Doran French pub-lished an article in which he had used cluster analysis with groups of rejected boys and found thatthere were two clear subtypes of rejected boys: aggressive and nonaggressive (French 1988). Thedemonstrated heterogeneity of the rejected children (also French 1990) was very much in line withmy own thinking and empirical results. Gradually, it became necessary for US peer researchers totalk about and do research on rejected-aggressive and rejected-withdrawn children as two sepa-rate groups. The sociometric label “rejected” was thus too broad and included children with verydifferent personalities and behavioral profiles. This heterogeneity could probably also explain whyseveral interventions focusing on rejected children (cf. Asher & Coie 1990) had been relativelyunsuccessful, since rejected-aggressive and rejected-withdrawn children would very likely needdistinctly different kinds of therapy or interventions (French 1988, Olweus 1989).
An additional problem with the sociometric likeability classification system was evident whenPhilip Rodkin and colleagues published an article in 2000 titled “Heterogeneity of popular boys:antisocial and prosocial configurations” (Rodkin et al. 2000). The results in this article showed thesame kind of heterogeneity with regard to popularity that had previously been demonstrated forrejection. The authors called the two different types of boys “model boys” and “tough boys.” Theauthors of this article were all students of and/or collaborators with Robert Cairns, who had devel-oped a new technique for the identification of peer cliques or subgroups and the relative centralityof the clique members. This technique was named social-cognitive mapping and was largely basedon student reports on “people in the class/school who hang around a lot” (Cairns & Cairns 1994,Cairns et al. 1989). Somewhat earlier than the Rodkin et al. article, Luthar & McMahon (1996) andParkhurst & Hopmeyer (1998) had shown that sociometric status/acceptance/likeability and per-ceived popularity (centrality, social dominance, visibility) were relatively weakly related and shouldbe best regarded as two distinct dimensions. Obviously, also the sociometric label popular was toobroad and included children and youth with very different personalities and behavioral profiles.
A recent paper by Mayeux & Cillessen (2008) has, maybe somewhat indirectly, pointed to yetanother potential problem with the dimension or label popular. What they showed was that thecorrelation between peer and self-perceptions of popular status both in the form of social pref-erence (sociometric status) and perceived popularity was weak, with correlations in the 0.10–0.30range. Obviously, many (junior high school) students simply did not know—did not have accurateperceptions—of their own social status in their peer group. Such findings raise the issue of the ex-tent to which sociometric labels such as popular or rejected actually correspond to distinct personalexperiences and can be conceptualized as meaningful potentially causal variables, for example.
In sum, although a very great number of articles, book chapters, and books have been publishedwithin the research paradigm focusing on likeability, it is my conclusion that the yield in theform of meaningful, replicated knowledge of what actually goes on in peer groups has beenrelatively meager. It appears to me that the availability of a convenient measurement technique
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Figure 3PsycINFO database citations located that use the words bully, bullying, or bullied. Updated on July 24, 2012.
and classification system did take precedence over conceptualization and problem formulation. Inmy view, this also contributed to preventing new ideas, approaches, and themes such as bullyingfrom coming into focus for quite some time.
In my symposium contribution in 1989, I called for a reorientation, and this call was reiteratedin my chapter (Olweus 2001) in the book edited by Juvonen & Graham (2001), this time in asomewhat more optimistic tone. And the developments in the late 1990s and subsequent yearswith a focus on perceived popularity as largely distinct from likeability/sociometric popularityseem to be a step in the right direction. This research is relatively closely related to the qualitative,ethnographic studies of peer relations conducted by educational sociologists such as Eder (1995)and Adler & Adler (1998). Although it is difficult to know to what extent the often extremelycomplex and subtle processes described by Eder and the Adlers can be replicated and generalized,the strong emphasis on power mechanisms and struggles in the peer group seems intuitivelymeaningful and important. The new developments among US peer relations researchers with astronger focus on perceived popularity characterized by terms such as social dominance, centrality,and visibility also make it clear that the power dimension is a key aspect of peer relations. Asdocumented in the recently published comprehensive Handbook of Peer Interactions, Relationships,and Groups (Rubin et al. 2009), for example, the approach to the study of peer relations taken bypresent-day researchers is clearly much broader and more varied than the approach taken 10 yearsago.
In parallel with this new trend, the past decade has also witnessed a marked general “reorienta-tion” with regard to research on bully/victim problems. Figure 3, which portrays the number ofPsycINFO database citations (articles, books, book chapters, etc.) of the words bully, bullying, andbullied, clearly illustrates this development, with an approximately 100-fold increase of citationsper year from 1990 to 2012. A similar development from 1978 to 2005 was shown in a paper byBerger (2007), who talked about an “explosion” of research on bully/victim problems and declaredthat “Within the past 15 years, scholars have shifted from indifference to fascination regardingbullies” (p. 91). This development is also documented in a number of edited books such as thoseby Juvonen & Graham (2001), Espelage & Swearer (2004), and Jimerson et al. (2010).
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SOME REASONS FOR FOCUSING ON BULLY/VICTIM PROBLEMS
Before closing, I would like to briefly point out some aspects of bully/victim problems, which inmy view make them attractive and interesting from both a research and an intervention/preventionperspective:
� The implicated behaviors and reactions are anchored in a social context, and there is aprimary focus on perpetrator(s)/aggressor(s), targets/victim(s), bystanders, and the peergroup(s). Generally, this entails a more or less direct attention to the power dynamics in thepeer group.
� A focus on bully/victim problems leads naturally to an examination of larger units orcontexts (a multilevel or ecological approach): classes, schools, and communities and relatedaspects including teacher behavior, classroom norms, social psychological mechanisms,and school policy. With such an approach, multilevel techniques (e.g., Heck et al. 2010,Raudenbush & Bryk 2003) are both necessary for adequate statistical treatment of researchdata and very helpful in conceptualizing and analyzing relationships and influences at andacross different levels.
� A considerable portion of what characterizes bully/victim problems can be conceptualizedin a causal-analytic framework. The implicated behaviors and reactions represent real peerexperiences (possible causal factors) with often quite serious short- and long-term conse-quences for the individuals involved and their families and partners. Longitudinal studiesmake it clear that these problems also constitute a major, not fully realized, public healthissue with great costs to society (Olweus & Breivik 2013).
� A simple description of the problems usually provides a good rationale for intervention onwhich it is relatively easy to reach consensus (at least in principle): no acceptance. The suffer-ing of the victim(s) is the main motivation behind intervention, and this can be linked to theUN Convention on the Rights of the Child and to the obligation of schools to provide a safelearning environment for every child (possibly expressed in legislation). Prevention of suchproblems also represents large economic gains to society (see, e.g., Olweus & Limber 2010).
� Antibullying work, in particular of the whole-school kind, provides a good entry point forpositive school change or organizational development more generally, which will benefit allstudents in the school.
� A focus on bully/victim problems should also be highly rewarding for both researchers andinterventionists by providing ample opportunities to make life safer and happier for largenumbers of children and youth.
CONCLUDING WORDS
Looking back on the more than 40 years since my research interest in bullying problems was firstinitiated, there are two developments that I see as particularly striking and rewarding. The firstdevelopment is the fact that there has occurred a dramatic change in many countries in the worldin the perception of bully/victim problems: from being regarded as a natural part of growingup to being viewed as a pressing social and public health issue that schools and the educationalauthorities must take seriously and counteract. The second is the documentation and (maybestill partial) understanding that it is quite possible to considerably reduce these problems with aresearch-based intervention program that is implemented with some degree of fidelity.
DISCLOSURE STATEMENT
The author is not aware of any affiliations, memberships, funding, or financial holdings that mightbe perceived as affecting the objectivity of this review.
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ACKNOWLEDGMENTS
Some of the research reported in this review was financially supported by the Norwegian Ministryof Children and Family Affairs (BLD) and the Norwegian Ministry of Education and Research,which is gratefully acknowledged. Thanks also to my collaborator Kyrre Breivik for valuablecomments on the manuscript.
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CP09-FrontMatter ARI 9 March 2013 1:0
Annual Review ofClinical Psychology
Volume 9, 2013 Contents
Evidence-Based Psychological Treatments: An Updateand a Way ForwardDavid H. Barlow, Jacqueline R. Bullis, Jonathan S. Comer,
Endophenotypes in Psychopathology Research: Where Do We Stand?Gregory A. Miller and Brigitte Rockstroh � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 177
Fear Extinction and Relapse: State of the ArtBram Vervliet, Michelle G. Craske, and Dirk Hermans � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 215
Social Anxiety and Social Anxiety DisorderAmanda S. Morrison and Richard G. Heimberg � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 249
Worry and Generalized Anxiety Disorder: A Review andTheoretical Synthesis of Evidence on Nature, Etiology,Mechanisms, and TreatmentMichelle G. Newman, Sandra J. Llera, Thane M. Erickson, Amy Przeworski,
Cognitive Interventions Targeting Brain Plasticity in the Prodromaland Early Phases of SchizophreniaMelissa Fisher, Rachel Loewy, Kate Hardy, Danielle Schlosser,
