Identifying Young Children with Language Impairments: Measurement Issues Mabel L. Rice Presentation...

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Identifying Young Children with Language Impairments:

Measurement IssuesMabel L. Rice

Presentation at ASHA Conference for Speech-Language Pathologists in Schools 

Nashville, TennesseeSaturday, July 13, 2002

The Problem of Identification Kindergarten children with Specific Language

Impairments (SLI) can be difficult to identify (cf. Only 29% of kindergarten children known to have SLI were enrolled in intervention; Tomblin et al., 1997)

Variation in rates of language acquisition among young unaffected children adds to the complexity of identification of affected children

Conventional Measures, and the Normal Curve Assumption for Language Assessment

Assumption of an age-referenced normal distribution of children on a general language dimension

Num

ber

of

Child

ren

Performance Level

Related properties About 16% score 1 SD or more below the

mean About 2% score 2 or more SD below the

mean About 66% score within 1 SD of the mean

Positive applications Determine the prevalence of SLI (about 7%

in 5-year-olds; Tomblin et al., 1997) Determine the likelihood of speech

impairments with language impairment (less than 2% in the general population of 5-year-olds; Tomblin et al., 1997)

Determine long-term prognosis (individuals are likely to remain in the low levels of performance; Johnson et al., 1999)

Limitations No intrinsic cut-off score for “affected” No obvious way to interpret the test score in

terms of particular linguistic content No way to interpret a child’s progress toward

the adult grammar

A Grammatical Marker Approach Obligatory properties of clausal

structure These balls/*these ball She is walking/*she walking She walks outside/*she walk outside Yesterday she walked

outside/*yesterday she walk outside Does she like to walk?/*she like to walk?

Distributional Properties of a Grammatical Marker

Sensitivity and Specificity Sensitivity: rate of identifying true cases of

affectedness Specificity: rate of identifying true cases of

unaffectedness

Clinical Characteristics of a Grammatical Marker

By a certain age, grammatical markers would show little variation across unaffected children

Affected children would perform below the unaffected children

High levels of sensitivity and specificity Content would be meaningful for interpretation

of a child’s language deficits Child’s performance would be interpretable in

terms of the adult grammar Markers could persist over time

A Finiteness Grammatical Marker Theoretical Linguistics

Morphology and syntax are related in the area of morphosyntax

Finiteness is a property of clause structure that shows up as verbal forms inflected for tense and/or subject/verb agreement

Examples of finiteness markers Patsy walks home (third person singular subject, present

tense) Patsy walked home yesterday (no subject agreement,

regular past tense) Patsy ran home yesterday (no subject agreement, regular

past tense) Patsy is walking (third person singular subject, auxiliary

present tense) Patsy is happy (third person singular subject, copular

present tense) Does Patsy walk home? (third person singular, auxiliary

present tense)

In English, young children grow into consistent use of finiteness markers, during a period of Optional Infinitives (Wexler, 1994), evident in dropped finiteness markers, thought to be related to the need to mark grammatical tense (TNS).

Research with Young Children with SLI

Criteria for SLI in Rice Longitudinal Study Inclusionary

Expressive language: Low MLU Receptive language: Low comprehension

vocabulary (PPVT) Low performance on standardized omnibus

language test

Exclusionary No hearing loss Nonverbal IQ in normal range or above No known neurological or psychosocial problems Passed a phonological screening

Outcomes of Research

SLI children start later, and show slower acquisition timing although similar growth curves

Composite Tense

Age in Years

87;676;665;654;643;63

Me

an

Pe

rce

nt C

orr

ect

100

80

60

40

20

5N

3N

SLI

Grammatical marker is apparent in judgments as well as productions

A' Adult Versus OI Grammar

Age in Years

87;676;665;654;64

Mea

n A

' S

core

s

1.0

.9

.8

.7

.6

5N

3N

SLI

Young children show variation that disappears by age 5 years, at adult grammar

Composite TNS Scores Over Time

Age in Years

87;676;665;654;643;63

Sco

re

100

80

60

40

20

0

3N

SLI

OI A': Growth Curve

Age in Years

87;676;665;654;64

A' S

co

res

1.0

.8

.6

.4

.2

0.0

3N

SLI

SLI children show variation in a range far below age expectations

At the same time of variation as TNS-marking, other elements of morphosyntax are unaffected

Regular -s Plurals

Age in Years

87;676;665;654;643;63

Mean P

erc

ent C

orr

ect

100

80

60

40

20

5N

3N

SLI

Lexical indices show consistent variation across the growth curve, and do not differentiate SLI from younger language-equivalent children

PPVT Raw Scores

Age

8.07.06.05.04.03.0

Score

120

100

80

60

40

20

0

5N

3N

SLI

Timing of acquisition differs for morphosyntactic and morphophonological components of TNS-marking Past tense variables

Regular (e.g., walked) Finite (e.g., fell/falled) Irregular (e.g., fell)

Past TNS probe: SLI Group

Round

7654321

Mean P

erc

enta

ge

100

80

60

40

20

0

Regular past probe

% correct

Irregular past probe

% finite

Irregular past probe

% correct

Past TNS probe: 3N Group

Round

7654321

Mean P

erc

enta

ge

100

80

60

40

20

0

Regular past probe

% correct

Irregular past probe

% finite

Irregular past probe

% correct

Past TNS probe: 5N Group

Round

7654321

Mean P

erc

enta

ge

100

80

60

40

20

0

Regular past probe

% correct

Irregular past probe

% finite

Irregular past probe

% correct

Growth curve components and predictors of growth are similar for TNS/finiteness indices, but differ from morphophonological index TNS productions

Linear and quadratic components for SLI and MLU groups; same curves for both groups

Non-predictors: Intelligence, vocabulary (PPVT-R), mother’s education

Predictor: MLU

Grammaticality Judgments: OI Grammar/Bad Agreement Grammar Linear and quadratic components for SLI and

MLU groups; same curves for both groups Non-predictors: Intelligence, vocabulary (PPVT-

R), mother's education Predictor: MLU

Irregular past tense Linear growth only, for both groups Non-predictors: Mother's education Predictors: MLU, vocabulary, intelligence

Finite Past Tense Linear and quadratic components for SLI and

MLU groups; same curves for both groups Non-predictors: Intelligence, vocabulary,

mother's education Predictor: MLU

Conclusions: TNS/AGR marking (finiteness) follows growth curves that are linear + quadratic in shape and growth is not predicted by intelligence, vocabulary or mother's education, and is positively predicted by MLU, although not strongly. When morphophonological accuracy is included in the measurement, the growth curve becomes linear only and the predictors shift to include a child's vocabulary and non-verbal intelligence.

Rice/Wexler Test of Early Grammatical Impairment

Advantages compared to other language measures Focus on finiteness is conceptually sound in

terms of the linguistic properties of adult grammar

Performance can be directly interpreted as describing fundamental properties of what a child knows about grammar

Performance can be interpreted in terms of a child's progress toward the adult grammar

Content focuses on a property of English grammar that is known to be well mastered by children before they enter school

Focuses on a property of grammar known to be difficult for children with language impairments

Can identify affected children whose sole developmental deficit is language impairment (i.e., SLI)

Well suited to identify children of school-entry age who need early intervention

High levels of sensitivity and specificity, leading to accurate identification of affected children, without a high rate of false identification of unaffected children

Includes a screening version

General Overview Consists of five probe tasks and screener:

Phonological Third person singular Past tense BE/DO Grammaticality judgment Screener portion is average of third person

singular and past tense

For children ages 3 to 8 years Normed to two groups of children per 6-

month age interval: Language impaired group and control (normal) group

Procedures not usually found in conventional language tests Phonological probe as screening for test

appropriateness Attention to the syntactic context for

morphological assessment Focus on a morphological class instead of an

individual item (e.g., regular verb morphology and class of these verbs instead of a particular lexical item)

Differentiation of grammatical functions of a given morpheme (e.g., BE copula vs. auxiliary, questions vs. statements)

Percentage correct of "attempted structures" instead of items correct/total items (i.e., partitioning of off-task or irrelevant items out of scoring)

Calculation of multiple outcomes scores, to form composites and to be considered individually

Video demonstration of procedures

Tryout and Standardization Sampling

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Outcomes

Growth curves – percentiles and means per age, with reference to normal samples

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Specificity/selectivity, with reference to normal and affected samples (bimodal distribution) percentage children per age group above or below a given level of performance

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Criterion Scores Suggested "cut points" for performance

within the normal range, referenced to affected group as well as normal group, with at least 80% sensitivity Example: For screening subtests for age range

of 4.06 to 4.11, criterion = .65

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Further Data Reporting

Means and standard deviations per measure, per group, per age level

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Box and whiskers plot to show within group variation per measure per age level

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Reproduced by Permission. Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychology Corporation.

Using the Rice/Wexler in Clinical Practice

Establishing eligibility for services As a screening tool Interpreting the Rice/Wexler scores

Elicited grammar composite Phonological probe Third person singular Past Tense BE/DO Grammaticality Judgments

Comparisons with related test data Interpreting children's performance

relative to nonverbal intelligence and parental education levels

Concluding Comments A "marker" approach to identification adds

a valuable clinical resource to assessment tools

Estimates of sensitivity and specificity provide valuable reference points for establishing criteria for identification and tracking a child's progress level

Theoretically motivated research can generate new evidence that leads to new clinical instruments and new approaches to assessment

ReferencesBedore, L. M., & Leonard, L. B. (1998). Specific Language Impairment

and grammatical morphology: A discrimination function analysis. Journal of Speech, Language, and Hearing Research, 41, 1885-1192.

Fey, M. E., & Loeb, D. F. (2002). An evaluation of the facilitative effects of inverted yes-no questions on the acquisition of auxiliary verbs. Journal of Speech, Language, and Hearing Research, 45, 160-174.

Cleave, P. L., & Rice, M. L. (1997). An examination of the morpheme BE in children with specific language impairment: The role of contractibility and grammatical form class. Journal of Speech, Language, and Hearing Research, 40, 480-492.

Johnson, C. J., Beitchman, J. H., Young, A., Escobar, M., Atkinson, L., Wilson, B., Brownlie, E. G., Douglas, L., Taback, N., Lam, I., & Wang, M. (1999). Fourteen-year follow-up of outcomes. Journal of Speech, Language, and Hearing Research, 42, 744-760.

Norbury, C. F., Bishop, D. V. M., & Briscoe, J. (2001). Production of English finite verb morphology: A comparison of SLI and mild-moderate hearing impairments. Journal of Speech, Language, and Hearing Research, 44, 165-178.

Oetting, J. B., & McDonald, J. L. (2001). Nonmainstream dialect use and specific language impairment. Journal of Speech, Language, and Hearing Research, 44, 207-223.

Paradis, J., & Crago, M. (2000). Tense and temporality: A comparison between children learning a second language and children with SLI. Journal of Speech, Language, and Hearing Research, 44, 834-847.

Paradis, J., Crago, M., Genesee, F., & Rice, M. L. (2001, June). French-English bilingual children with SLI: How do they compare with their monolingual peers? Poster presented at the Symposium for Research on Children with Language Disorders, Madison, WI.

Redmond, S. M., & Rice, M. L. (1998). The socioemotional behaviors of children with SLI: Social adaptation or social deviance? Journal of Speech, Language, and Hearing Research, 41, 688-700.

Rice, M. L. (1999, July). GAPS over time: Longitudinal observations of children with SLI. Paper presented at the VIIth congress of the International Association for the Study of Child Language, San Sebastian, Spain.

Rice, M. L. (2000). Grammatical symptoms of specific language impairment. In D. V. M. Bishop & L. B. Leonard (Eds.), Speech and language impairments in children: Causes, characteristics, intervention and outcome. East Sussex, UK: Psychology Press Ltd.

Rice, M. L. (in press). A unified model of specific and general language delay: Grammatical tense as a clinical marker of unexpected variation. To appear in Y. Levy & J. Schaeffer (Eds.), Language competence across populations: Toward a definition of SLI: Mahwah, NJ: Lawrence Erlbaum.

Rice, M. L., & Bode, J. (1993). Gaps in the verb lexicons of children with specific language impairment. First Language, 13, 113-131.

Rice, M. L., Mervis, C., Klein, B. P., & Rice, K. J. (1999, November). Children with Williams syndrome do not show an EOI stage. Paper presented at the Boston University Conference on Language Development, Boston.

Rice, K. J., Rice, M. L, & Redmond, S. M. (2000, June). MLU outcomes for children with and without SLI: Support for MLU as a matching criterion. Paper presented at the Symposium on Research in Child Language Disorders, Madison, WI.

Rice, M. L., Spitz, R. V., & O'Brien, M. (1999). Semantic and morphosyntactic language outcomes in biologically at-risk children. Journal of Neurolinguistics, 12, 213-234.

Rice, M. L., & Tomblin, B. (1999, June). Clinical indices of language impairment: Grammatical tense compared to conventional testing. Poster presented at the Symposium on Research in Child Language Disorders, Madison, WI.

Rice, M. L., Tweed, S., & Higheagle, B. (2000, June). GAP verbs of children with SLI: Longitudinal observations. Paper presented at the 21st Annual Symposium on Research in Child Language Disorders, Madison, WI.

Rice, M. L., & Wexler, K. (1996). Toward tense as a clinical marker of specific language impairment in English-speaking children. Journal of Speech, Language, and Hearing Research, 39, 1239-1257.

Rice, M. L., & Wexler, K. (2000, November). What she saying? SLI children's judgments of questions. Paper presented at the Boston University Conference on Language Development, Boston.

Rice, M. L., & Wexler, K. (2001). Rice/Wexler Test of Early Grammatical Impairment. San Antonio, TX: The Psychological Corporation.

Rice, M. L., Wexler, K., & Cleave, P. (1995). Specific language impairment as a period of extended optional infinitive. Journal of Speech and Hearing Research, 38, 850-863.

Rice, M. L., Wexler, K., & Hershberger, S. (1998). Tense over time: The longitudinal course of tense acquisition in children with specific language impairments. Journal of Speech, Language, and Hearing Research, 41, 1412-1431.

Rice, M. L., & Wexler, K. (1995). A phenotype of specific language impairment: Extended optional infinitives. In M. L. Rice (Ed.), Toward a genetics of language (pp. 215-237). Mahwah, NJ: Lawrence Erlbaum Associates, Inc.

Rice, M. L., Wexler, K., Marquis, J., & Hershberger, S. (2000). Acquisition of irregular past tense by children with specific language impairment. Journal of Speech, Language, and Hearing Research, 43, 1126-1145.

Rice, M. L., Wexler, K., & Redmond, S. M. (1999). Grammaticality judgments of an extended optional infinitive grammar: Evidence from English-speaking children with specific language impairment. Journal of Speech, Language, and Hearing Research, 42, 943-961.

Shriberg, L. D., Tomblin, J. B., & McSweeny, J. L. (1999). Prevalence of speech delay in 6-year-old children and comorbidity with language impairment. Journal of Speech, Language, and Hearing Research, 42, 1461-1481.

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Tomblin, J. B., Records, N. L., Buckwalter, P., Zhang, Z., Smith, E., & O'Brien, M. (1997). Prevalence of specific language impairment in kindergarten children. Journal of Speech, Language, and Hearing Research, 40, 1245-1260.

Watkins, R. V., Rice, M. L., & Moltz, C. C. (1993). Verb use by language-impaired and normally developing children. First Language, 13, 113-131.

Wexler, K. (1994). Optional infinitives, head movement and the economy of derivations. In D. Lightfoot & N. Hornstein (Eds.), Verb movement. Cambridge, England: Cambridge University Press.

Wexler, K. (in press). Lenneberg's dream: Learning normal language development, and specific language impairment. To appear in Y. Levy & J. Schaeffer (Eds.), Language competence across populations: Toward a definition of SLI. Mahwah, NJ: Lawrence Erlbaum.

Zhang, S., & Tomblin, J. B. (2000). The association of intervention receipt with speech-language profiles and social-demographic variables. American Journal of Speech-Language Pathology, 9, 345-357.