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The Perception of RiskMessages RegardingElectromagnetic Fields:Extending the ExtendedParallel Process Model toan Unknown RiskShari McMahan , Kim Witte & Jon'a MeyerVersion of record first published: 10 Dec2009.

To cite this article: Shari McMahan , Kim Witte & Jon'a Meyer (1998): ThePerception of Risk Messages Regarding Electromagnetic Fields: Extending theExtended Parallel Process Model to an Unknown Risk, Health Communication,10:3, 247-259

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HEALTH COMMUNICATION, 10(3), 247-259 Copyright O 1998, Lawrence Erlbaum Associates, Inc.

The Perception of Risk Messages Regarding Electromagnetic Fields:

Extending the Extended Parallel Process Model to an Unknown Risk

Shari McMahan School of Social Ecology

University of California, Irvine

Kim Witte Department of Communication

Michigan State University

Jon'a Meyer Department of Sociology

Rutgers University

The Extended Parallel Process Model (EPPM) was developed as a model to assist in the development of effective risk communication messages, specifically messages that elicit adaptive behavioral responses. It has shown to be effective in several settings invoking clearly delineated dangers (e.g., safety belt usage, condom usage). Unfortunately, communicating risk messages is not always so straightforward. One increasing concern in the risk communication field is the controversy over electro- magnetic fields (EMFs) and the uncertain hazards they present to individuals. The purpose of this study is to test the EPPM with this unknown risk and to explore which type of risk message may motivate adaptive behavioral responses. In accordance with the EPPM model, 251 participants received either a low- or high-threat risk message and a list of control measures they could use to reduce their exposure to EMFs. Results suggest that the EPPM model can be extended to an unknown risk.

The Extended Parallel Process Model (EPPM) was developed by Witte (1991) as a model t o assist in the development of effective risk communication messages,

Requests for reprints should be sent to Shari McMahan, School of Social Ecology, University of California, I ~ i n e , CA 92697. E-mail: smcmahan@ecology.soceco.uci.edu

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248 MCMAHAN, WITTE, MEYER

specifically messages that elicit adaptive behavioral responses to the threat of AIDS infection. The EPPM integrates 40 years of empirical research on risk perception and incorporates three major theoretical approaches: the fear-as-acquired-drive model (Hovland, Janis, & Kelly, 1953; Janis, 1967); the parallel process model (Leventhal, 1970); and protection motivation theory (Rogers, 1975, 1983).

The EPPM proposes that in response to a risk message, individuals initially evaluate the threat represented by the hazard. This is termed the primary appraisal. If the individual perceives the threat to be insignificant, the risk message is too weak to elicit any response. If the threat is perceived to be meaningful (e.g., severe or relevant), however, the individual is then motivated to consider the recommended response. This next process is termed the secondary appraisal. The greater the perceived significance and relevance of the threat, the greater is the motivation to begin the secondary appraisal.

When a threat is perceived as high, the results of the secondary appraisal determine whether individuals will implement danger-control responses (i.e., adap- tive behavioral changes) or fear-control responses (i.e., defensive avoidance). Of course, the intention of the risk message is to elicit danger-control responses so that fear-control responses are undesirable.

The EPPM proposes that risk messages can elicit both types of responses. Individuals may respond to high-threat messages by choosing fear-control re- sponses when they feel they cannot avoid the threat. Perceived efficacy is low in this case, leading to defensive avoidance, message derogation, or perceived ma- nipulation to reduce fear. Such individuals would be more likely to simply dismiss the message itself or otherwise cast aspersions on their need to take action. The message then loses its potential to create behavioral change.

If individuals believe they can easily and effectively avoid the threat, on the other hand, perceived efficacy is high and danger-control processes dominate. In this case, risk messages can be effective in motivating protective behaviors.

Overall, in order to be effective, risk messages must contain both a threat component (which creates a perception of personal susceptibility and severity) and an eficacy component (which provides information about measures the reader is able to employ to reduce the threat). Unfortunately, things are not always so straightforward in communicating risk messages. Deficiencies in scientific knowl- edge, lack of expert consensus, and the public's use of qualitative risk factors such as "voluntariness" or "dread" in making risk judgments play a role in making risk messages difficult to design.

The EPPM has the capacity to help us design effective risk messages--especially for those risks that arouse great levels of fear. By focusing message writers on the elements necessary to create change, the EPPM offers insight into how to channel an individual's fear into a motivator for effective action, rather than into an inhibitor of self-protective behavior.

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UNKNOWN RISKS

One increasing concern has been the controversy over electromagnetic fields (EMFs). Two peculiarities of EMFs create difficulties in determining effective risk-reduction strategies. First, findings suggest that EMFs may not follow a typical dlose-response relation. For example, some biological effects that are seen at lower exposure levels are not found at higher levels (Blackman, Benane, Elliot, House, & Pollock, 1988; Blackman, Kinney, House, & Joines, 1989). In laboratory studies, there is a greater efflux of calcium that occurs between cell membranes. As the intensity increases, the effects diminish. If the same principle were extrapolated to humans, reducing exposure could theoretically lead to greater risk.

The second difficulty is the nature of hazard. It is not known at this time what specific aspect of exposure to EMFs is significant (National Institute of Environ- mental Health Sciences & US. Department of Energy, 1995). For example, is it the average time of exposure that causes health effects, or is it peak field strength? Studies have found support for each of these two hypotheses. Accurate risk messages, then, may be very difficult to fashion.

This does not mean that EMFrisk messages must always be hygienically sterilized t~o exclude any mention of potential harms about which science is uncertain. In the absence of scientific certainty, Morgan (1989) argued that we have a moral obligation to tell the public that exposure to EMF may adversely affect their health and to inform them that people should avoid EMF exposure when it is reasonable, practical, relatively inexpensive, and simple to do so. Witte (1994) suggested that even if the true risk of a hazard is unknown, risk managers can prevent panic responses by (a) acknowledging this uncertainty, and (b) offering specific steps that individuals can take to effectively reduce the occurrence of the threat or minimize harm firom the threat should it occur. According to this line of reasoning, EMF risk messages should concede that the exact harm caused by EMFs is unknown but should still present risk minimization strategies "just in case" they really are unsafe.

The purpose of this study is test the EPPM with an unknown risk, EMFs, and to explore which type of risk message may motivate adaptive behavioral responses to unknown risks. That the true nature of EMFs is uncertain makes them an ideal way to test the EPPM's generalizability from more easily understood hazards (e.g., injuries due to operating heavy factory machinery) to risks that are difficult to discuss in undebatable terms.

METHODS

Participants

The participants were 25 1 college undergraduates who were offered extra credit for their participation in the study. The participants were told that educational

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materials about EMFs, targeted for college students, were being developed and that it was essential to receive their honest opinions and responses to the materials so that they could be further refined. Each participant was randomly assigned to either the low-threat or high-threat message group.

The sample was predominately female (66%, n = 165) and single (94%, n = 237). Nearly half (48%, n = 121) were Asian; the remainder were White (21%, n = 53), Hispanic (14%, n = 35), and other ethnicities. The participants ranged in age from 19 to 39 years; the mean age was 22. Although the participants were college students, no particular field of study predominated; roughly equal numbers were in social sciences, applied social sciences, and physical sciences. These demographics are reflective of the population at the campus where the study took place.

Procedures

Following an experimental design, naive participants were asked to complete questionnaires immediately after exposure to a risk message concerning EMF exposure. Each participant was also provided with his or her own copy of a list of recommendations for reducing exposure.

Risk Messages

Each participant received either a low- or high-threat risk message. Both messages included an explanation of the properties of EMFs, a brief summary of the findings of epidemiological studies regarding EMF and health effects, and an acknow- ledgment of scientific uncertainty regarding exposure assessment. Both messages also discussed the source of EMFs (the nature of the hazard) and the suggestion that exposure levels can be reduced by simply increasing one's distance from electrical devices, especially household appliances.

Although there were many similarities between the messages, the high- threat message was designed to produce high perceived severity and suscep- tibility and the low-threat message was designed to produce low perceived severity and susceptibility. The low-threat message informed the reader that some EMFs occur naturally (e.g., due the earth's magnetic fields), whereas the high-threat message did not discuss this natural source of EMFs and instead emphasized that EMFs are invisible and cannot be detected by hu- mans. Unlike the low-threat message, the high-threat message used the term radiation and presented exposure estimates for a typical home and near electrical household appliances. In addition, the high-threat message men- tioned that some studies have linked childhood cancer to EMFs, whereas the low-threat message stressed the inconclusiveness regarding health effects studies in the literature.

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RISK MESSAGES AND ELECTROMAGNETIC FIELDS 251

Because low perceptions of efficacy typically promote maladaptive responses in which individuals act contrary to what is advocated, efficacy perceptions were not manipulated. Due to these ethical concerns, existing perceptions of efficacy were used in the analysis when examining how efficacy and threat work together to influence safety behaviors.'

Questionnaire Construction: Measures

Demographic variables. In addition to the demographics discussed pre- viously, the questionnaire also asked for proximity of home to power lines and time spent per day using electrical appliances. The average distance from the partici- pants' homes to the nearest power lines was 348 ft, and the average participant spent roughly 2% hours per day using electrical appliances. In addition, the survey assessed the degree to which participants trusted various sources of information, such as the news media, physicians, friends, and so forth, as well as whether or not they thought EMF caused a variety of diseases (e.g., breast cancer, brain tumors, leukemia, etc.). The influence of these demographic variables was controlled for in the multivariate analysis when the results were significantly affected.

The questionnaire asked about each of the six domains important to the EPPM: susceptibility, severity, response efficacy, self-efficacy, danger-control outcomes (i.e., fear, attitudes, intentions, and behaviors), and fear-control outcomes (e.g., defensive avoidance, perceived manipulation, derogation). Following the format employed by the EPPM, 5-point Likert-type response formats were used to assess participants' perceptions along the domains. The measures are briefly described in the following.

Perceived threat. The threat construct contained two dimensions, suscepti- bility and severity. Thus, two questions assessed whether participants thought EMFs would be harmful to their health (e.g., "It is likely that exposure to electro- magnetic fields will be harmful to my health"; a = .75), and another three questions assessed whether they thought health effects related to exposure to EMFs are "severe," "significant," and "serious" ( a = .91).

Perceived efficacy. Perceived efficacy was measured with three items for response efficacy (e.g., "Reducing exposure to electromagnetic fields is effective

either form of efficacy was intentionally manipulated as part of this study due to ethical concerns.

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252 MCMAHAN, WITTE, MEYER

in preventing unwanted health effects"; a = 3 2 ) and three items for self-efficacy (e.g., "Measures to control exposure to electromagnetic fields are inconvenient to use"; a = .72).

Fear. Fear arousal was measured by having participants rate, using a 5-point Likert-type scale ranging from 1 (strongly disagree) to 5 (strongly agree), how "frightened," "scared," and "anxious" they were about health effects from exposure to EMFs. Cronbach's Alpha was moderately high (.83) for this index.

Danger-Control Outcomes

Attitudes. Participants rated their attitudes toward reducing exposure to EMFs by providing the level of desirability to three index items on a 5-point Likert-type scale; for example "reducing exposure to electromagnetic fields with every use would be" 1 (extremely undesirable) to 5 (extremely desirable), a = 3 6 .

Intentions. Intent to use control measures was assessed with three items on a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree); for example, "I plan to use recommended control measures to reduce my exposure to electromagnetic fields with every use of electrical equipment/appliances", a = .94.

Behaviors. Self-reported behaviors were assessed through two items on a 5-point scale ranging from 1 (strongly disagree) to 5 (strongly agree); for example, "I currently use recommended control measures to reduce my exposure to electro- magnetic fields with every use of electrical equipment/appliances", a = 3 6 .

Fear-Control Outcomes

Defensive avoidance. Defensive avoidance was determined through an examination of the degree to which participants wanted to avoid thinking further about EMFs. Participants responded using the standard 5-point Likert-type scale utilized elsewhere in the study. For example, one statement read: "When I hear of health effects from exposure to electromagnetic fields, I spend additional time thinking about it" (a = 3 4 ) .

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RISK MESSAGES AND ELECTROMAGNETIC FIELDS 253

Message minimization. Message minimization, or denial of the importance of an EMF risk message, was determined through the measurement of the degree to which participants derogated or minimized the message (is., feelings and irnpressions of the message). The message minimization questions assessed whether participants thought the message was "exaggerated," "overblown," or "overstated (a = .93).

Perceived manipulation. The perceived manipulation questions were de- signed to determine the degree of reactance participants had against the EMF risk message. For this index, participants were asked whether they felt the message was "manipulative," "misleading," or "distorted" (a = .86).

RESULTS

Manipulation Checks

As expected, those who read the high-threat message (M = 3.79, SD = 0.86) were more likely to feel that EMFs posed serious health risks for themselves than those who read the low-threat message (M = 2.80, SD = 1.07, t(215) = -7.95, p < .0001). Similarly, those who read the high-threat message (M = 3.80, SD = 0.85) felt more susceptible to harm from EMFs than those who read the low-threat message (M = 3.43, SD = 0.95, (231) = -3 .23 ,~ < .001). In addition, those in the high-threat group (1M = 2.99, SD = 0.85) were significantly more afraid of harm from EMFs than their counterparts who read the low-threat message (M = 2.65, SD = 0.92, t(233) = -3.01, p < .01). Finally, the high-threat group (M = 2.66, SD = 0.99) was significantly more concerned than the low-threat group (M = 3.08, SD = 1.12) about harm from EMFs (t(229) = 3.16, p < .01).' Based on these results, it appears that the threat manipulation adequately produced high- and low-threat perceptions in the different conditions.

Confound Checks

There were no significant differences between the low- and high-threat groups with respect to response efficacy or self-efficacy. Similarly, there were no differences in perceived objectivity of the message, the perceived clarity of the message, the

-

2 ~ h e rating scale for concern was reversed (i.e., high concern = 1).

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254 MCMAHAN, WITTE, MEYER

level of understanding regarding EMFs after reading the message, and the degree to which individuals thought the message provided a useful source of knowledge about EMFs. Probably due to the greater amount of material presented to them, the high-threat group indicated greater learning (M = 3.46, SD = 1.13, t(236) = -3.69, p < .01) and perceived accuracy (M = 3.25, SD = 0.90, t(224) = -2.91, p < .001) from their risk message compared to the low-threat groups (M = 2.91, SD = 1.21; M = 2.89, SD = 1.05, respectively). The influence of these potential confounds was controlled for in the analysis when they significantly affected the results.

Overall Analyses

The EPPM suggests that threat motivates action but perceived efficacy determines the nature of that action. Specifically, it suggests an interaction between threat and efficacy, such that the high threat-high efficacy group will produce the strongest responses for danger control outcomes, and the other responses will be substantially weaker. Those in the low-efficacy groups will produce either no response (similar to those in low-threat conditions) or even boomerang responses, in which the opposite of what is advocated is conducted. The opposite pattern would be expected for fear-control responses, with the high threat-high efficacy group producing the least fear-control responses.

Therefore, a median split was performed to separate high perceived efficacy individuals from low perceived efficacy individuals (Mdn = 3.42) in order to create two efficacy groups. In order to assess the true effects of threat message and perceived efficacy on the danger-control and fear-control outcomes, the influence of demographics, prior beliefs about EMFs, and prior behaviors were controlled for in the analyses. Therefore, analysis of covariance was used to analyze the data in a Threat (high, low) x Perceived Efficacy (high, low) design.

Danger-Control Results

Attitudes. A significant main effect for efficacy was detected for attitudes, F(l, 93) = 9.61, p < .01. In addition, a significant interaction between threat and efficacy emerged, F(l, 93) = 3.94, p < .05, while controlling for several demo- graphic and prior beliefs and behaviors variables (i.e., marital status, time per day spent working on electrical appliances, beliefs that EMFs cause brain tumors and miscarriages, distance from one's home to nearest electrical lines, whether or not the lines could be seen from the home, and the degree of trust in physicians for information on EMFs). Consistent with EPPM predictions, threat motivated stronger or weaker attitudes, but efficacy determined whether the attitudes were

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RISK MESSAGES AND ELECTROMAGNETIC FIELDS 255

positive or negative. Those in the high-threat group with high-efficacy perceptions had the strongest attitudes (adjusted M = 4.34, SD = 0.74) toward EMF control measures whereas those in the high threat-low efficacy group had the weakest at~titudes (adjusted M = 3.38, SD = 0.87). Those in the low-threat groups, regardless of perceived efficacy level, had fairly neutral attitudes toward EMF control meas- ures (low threat-low efficacy, adjusted M = 3.64, SD = 0.89; low threat-high efficacy, adjusted M = 3.88, SD = 0.88).

Intentions. A significant main effect for efficacy on intentions emerged, F(1, 24.2) = 38.43, p < .001. No other significant main effects or interactions occurred. Although the interaction did not reach significance, the pattern was consistent with EPPM predictions in that the high threat-high efficacy participants had the strong- est intentions to engage in safety behaviors (M = 3.61, SD = 0.95). Those in the low threat-high efficacy group had somewhat weaker intentions (M = 3.34, SD = 1.1 I), and those in the low-efficacy groups, regardless of level of threat, had the weakest intentions (low threat-low efficacy M = 2.67, SD = 1.02; high threat-low efficacy M = 2.76, SD = 0.78).

Behaviors. A significant main effect for efficacy emerged for behaviors, F(1, 244) = 3.88, p < .05. No other main effects or interactions emerged. In this case, the low threat-high efficacy group had the strongest safety behaviors ( M = 2.57, SD = 1.011, followed by the high threat-high efficacy group (M = 2.41, SD = 0.86). However, Tukey's multiple range tests showed no significant differences between these two groups (i.e., the low threat-high efficacy group vs. the high threat-high efficacy group). The other groups had weaker safety behaviors (low threat-low efficacy, M = 2.13, SD = 0.99; high threat-low efficacy, M = 2.34, SD = 0.97). As in intentions, perceived efficacy in one's ability to perform an effective recom- mended response appears key in promoting safety behaviors.

Fear-Control Results

Defensive avoidance. A significant main effect for efficacy was found for defensive avoidance, F(1,242) = 1 1.24, p < .OO 1. No other significant main effects or interactions were found. As expected, those in the high threat-high efficacy group were least likely to report defensive avoidance (M = 3.54, SD = 1.09), as compared to those in the high threat-low efficacy (M = 3.08, SD = 0.99), low threat-high efficacy (M = 3.36, SD = 1.09), and low threat-low efficacy (M = 2.9 1, SD = 1.09) groups.

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Message minimization. A significant main effect for efficacy was found for message minimization, F(1, 241) = 33.99, p < .0001. No other significant main effects or interactions were found. As expected, those with low efficacy perceptions were most likely to perceive manipulation (M = 2.98, SD = 0.87), as compared to those with high-efficacy perceptions (M = 2.35, SD = 0.77). Those in the high threat-high efficacy group (M = 2.33, SD = 0.77) had the weakest levels of message minimization. All other groups had higher levels of message minimization (low threat-low efficacy M = 3.07, SD = 0.99; low threat-high efficacy M = 2.38, SD = 0.77; high threat-low efficacy M = 2.89, SD = 0.77).

Perceived manipulation. A significant main effect for efficacy was found on the perceived manipulation measure, F(1, 242) = 16.97, p < .0001. No other significant main effects or interactions were found. As expected, those with low-efficacy perceptions were most likely to perceive manipulation (M = 2.49, SD = 0.82), as compared to those with high-efficacy perceptions (M = 2.07, SD = 0.74). Those in the high threat-high efficacy and low threat-high efficacy groups had the weakest levels of perceived manipulation (M = 2.07, SD = 0.80 and M = 2.07, SD = 0.67, respectively), as compared to those in the low threat-high efficacy (M = 2.58, SD = 0.94) and high threat-low efficacy (M = 2.41, SD = 0.71) groups.

Multivariate Analyses

Additional analyses were undertaken to assess simultaneously the influence of the independent variables on intentions to use EMF control measures, using an ordinary least squares multiple regression.

The independent factors included fear (those who are more afraid should be more likely to desire to protect themselves from harm), whether participants felt health effects related to exposure to EMFs are severe (a motivational factor), and message type (those who received a high-threat message should be more likely than their counterparts reading a low-threat message to desire to reduce their exposure levels). In addition, response efficacy (those who feel that control measures would be effective in reducing adverse health effects should be more likely to want to implement them) and self-efficacy (participants who feel that control measures are inconvenient should be less likely to implement them) were entered into the equation. Current use of adaptive control behaviors was entered as a control variable, as current use of control measures may affect future intentions to imple- ment similar behaviors. We wished to include a second motivational factor, whether participants believed that EMFs were likely to endanger their health, but it was multicollinear with the first motivational factor (perceptions regarding severity of health effects, correlation = .66). No other variables were multicollinear with one another. The results are shown in Table 1.

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RISK MESSAGES AND ELECTROMAGNETIC FIELDS 257

TABLE 1 Ordinary Least Squares Regression Predicting Intent to Implement Control Measures

Variable B SE B I3 P

Threat group (1 = low, 2 = high) -.037 1 ,1190 -.0178 ,7557 Fear of EMFs ,3183 ,0686 .2773 ,0000 Self efficacy ,2710 .0446 .3038 .OW0 Response efficacy .2522 .0649 .2408 .0001 Severity of health effects .0690 . a58 .0719 ,2953 Current adaptive behaviors .I476 ,0542 .I444 ,0070 (Constant) ,0072 .2781 .9793

Note. Adjusted R~ = 40, F(6,237) = 27.84, p < .0001.

In this model, intentions to implement adaptive behaviors to reduce one's exposure to EMFs were related to perceived levels of fear, self-efficacy, and response efficacy. The EPPM model appears to hold true for unknown, as well as known, risks.

As predicted, those who were most afraid of the effects of EMF were more likely than their less-afraid counterparts to report that they would take steps to reduce their exposure to EMFs (P = .27, p = .0000). Beliefs about the efficiency of behavioral change also affected intentions to implement control measures. Those scoring high on response efficacy, for example, were more likely to report that they intended to reduce their exposure (P = .23, p = .0001). Similarly, those who reported current use of control measures were more likely to state that they would take action to reduce their EMF exposure (P = .l4, p < .01).

DISCUSSION

Because experts and lay persons process risk messages differently, it is critical to discover effective risk communication strategies to promote self-protective and adaptive behaviors. One model that helps the creators of risk messages is the EPPM model. Although this model has been used successfully with known risks, it had not been tested with an unknown risk (Witte, 1992,1994).

This study attempted to isolate the factors that lead to self-protective behaviors with unknown risks. The key reason identified for lack of adherence to risk messages has been fear. The EPPM notes that fear can be motivating or inhibiting, and that properly developed risk messages can motivate effective self-protective action. To channel fear into a motivator, people need to believe they have self-ef- ficacy and response efficacy. Specifically, people need to feel able to utilize recommended actions as well as to believe that those recommended actions effectively avert harm. This study showed that those people who were afraid of

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EMFs and had high levels of self-efficacy and response efficacy had the greatest intentions to adopt protective measures. Also, those people with the lowest levels of self-efficacy, indicating a perceived lack of ability to effectively avert harm from EMFs, were most likely to engage in fear-control responses such as defensive avoidance, message minimization, and perceived manipulation.

Thus, effective risk messages for unknown risks should promote high levels of perceived threat or fear and at the same time promote high levels of response and self-efficacy. As the study results indicate here, these types of messages result in stronger danger-control responses (in which people control the danger or threat) and weaker fear-control responses (in which people control their fear and ignore the threat). Specifically, the findings for attitudes and intentions showed that high-threat messages accompanied by high efficacy perceptions promoted the strongest intentions to engage in safety behaviors. Conversely, lower threat mes- sages with high-efficacy perceptions resulted in somewhat weaker intentions.

An exception to these findings was the behavioral results. Specifically, the behav- ioral results indicated that the low-threat message accompanied by high-efficacy perceptions promoted the most safety behaviors. However, multiple range tests indi- cated no significant differences between this group and the group expected to show the most safety behaviors (i.e., the high threat-high efficacy group). Therefore, it is possible that the means flipped due to chance alone (especially given the consistency of the other results like attitudes, defensive avoidance, perceived manipulation, etc.).

In sum, it is critical to note that when messages promote high perceived threat or fear at the expense of increases in response and self-efficacy, they run the risk of producing maladaptive fear-control outcomes. However, effective risk messages can motivate fear into greater safety behaviors by ensuring that individuals have high response and self-efficacy perceptions.

The generalizability of the findings needs to be interpreted with caution. Al- though studies have shown that college students perceive risks like other lay people, there has been little done in the way of evaluating ethnicity and risk perception of EMFs (Slovic, Fischhoff, & Lichtenstein, 1979). Studies in the future should sample a more heterogeneous population to rule out any potential biases.

The EPPM model may have important implications in the field of health communication. In the face of uncertainty, it is important to understand a model that could promote adaptive behavior. The EPPM may offer guidance to risk communicators interested In devising effective risk communication messages that yield the greatest public good.

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