About 45 R packages to analyze data using item response theory (IRT) have been developed over the last decade. This article introduces these 45 R packages with their descriptions and features. It also describes possible advanced IRT models using R packages, as well as dichotomous and polytomous IRT models, and R packages that contain applications…

Two types of classification error are possible in competency tests: erroneous classification of an individual as a "master" of the subject (Type II error), and erroneous classification of a master as a "nonmaster" of the subject (Type I). If steps are taken to minimize Type II errors, an artificially high number of true masters…

The taxonomy developed by J. Klecan-Aker et al. to investigate the use of various speech acts in response to questions during a structured picture-description task was evaluated. Results indicated that the taxonomy was sufficient to handle the responses of a group of 12 language-impaired children, aged 7-11. (JDD)

Self-Knowledge Development Theory (SKDT) by Weinstein and A. Alschuler (1985) is a structural developmental theory positing four stages in the development of self-knowledge. The Experience Recall Test-2 (ERT2) is described, which is the most recent instrument developed for assessing the SKDT. Self-knowledge is defined as the ability to describe…

The Groningen Social Disabilities Schedule for the assessment of social dysfunctioning of psychiatric patients is described. The measure is based on social role theory and the hierarchy in social disabilities as well as compatibility with the International Classification of Impairments. The semistructured measure allows for posing supplementary…

Forty parents of children with autism or pervasive developmental disorder completed the Wing Subgroups Questionnaire, developed for subclassifying children into one of L. Wing's three hypothesized subgroups. Results indicated that the questionnaire has adequate external criterion-referenced validity, with similar subgroup ratings made by…

Analysis of data from the Behaviour Disorder Scale for 405 adults and adolescents with intellectual disability revealed that subjects exhibited a mean of 14 problem behaviors per person. Factor analysis identified two general syndromes (a conduct syndrome and an emotional syndrome), raising the possibility of dealing with sets of problem behaviors…

This study examined the validity and internal and interrater reliability of the Wing Subgroups Questionnaire, an assessment that classifies children with autism into subtypes. Subjects were 42 students (ages 5 to 22) enrolled in multihandicapped special education classrooms. Findings support the reliability and validity of the questionnaire for…

This study examined effects of negative versus positive symptom formats on the assessment and subsequent classification of ADHD in children in public schools. Symptoms associated with the disorder based on the Diagnostic and Statistical Manual of Mental Disorders Fourth Edition (DSM-IV) were presented to parents and teachers of referred children…