The methodology of many studies that have identified specific genetic loci for disorders associated with mental retardation is criticized as failing to demonstrate an association between the behavior phenotype and the genetic marker. A more appropriate methodology using a multitrait-multimethod approach is suggested. (Author/JDD)

The 1992 American Association on Mental Retardation definition of mental retardation is critiqued. The definition is seen as lacking precision and necessitating identification dependent upon assessment of behavioral dimensions for which there are no reliable measurement instruments. These problems, which are attributed to advocacy concerns, are…

Examined the accuracy and validity of self-reports and their effect on tests of attitude-behavior relationships. Self-reports were reasonably accurate, but they produced results different from actual behavior in attitude-behavior tests. Concludes that self-reports and actual behavior should be measured, tested, and modeled separately. (Author/LS)

Ethnographic techniques were applied to a post hoc examination of children's incidental behaviors during a metalinguistic intervention procedure--behaviors ignored in the original experimental design. The reflective and qualitative nature of ethnography was used to account for the 12 phonologically impaired 4-year-olds' varied perceptions of…

Argues that rank order correlations may not be ubiquitously suitable for assessing the relations between children's behavior or characteristics at one age or in one situation, and those shown later or in another context. (HOD)

Even though attrition presents a serious threat to the validity of longitudinal research, there is a lack of standardization for reporting it. To examine the effectiveness of four tests for attrition -- two for external validity and two for internal validity -- the tests were applied to two large scale projects: the first, Project HASP, is a…