Exploratory factor analysis (EFA) is a widely used but poorly understood statistical procedure. This paper described EFA and its methodological variations. Then, key methodological variations were used to evaluate EFA usage over a 10-year period in five leading developmental disabilities journals. Sixty-six studies were located and evaluated on multiple procedural variations. Only 35% (n = 23) of studies used EFA; principal components analysis was the model used most often (n = 40, 61%). Orthogonal rotation was used most often (n = 39, 59%). A large portion of studies ran analyses with a subject: item ratio larger than 5:1 (n = 49, 74%). Most researchers employed multiple criteria for retaining factors (n = 45, 68%). Overall, results indicated that published recommendations and guidelines for the use of EFA are largely ignored.

The goal of this review was to examine the state of Level 2, caregiver-completed rating scales for the screening of Autism Spectrum Disorders (ASDs) in individuals above the age of three years. We focused on screening accuracy and paid particular attention to comparison groups. Inclusion criteria required that scales be developed post ICD-10, be ASD-specific, and have published evidence of diagnostic validity in peer-reviewed journals. The five scales reviewed were: the Social Communication Questionnaire (SCQ), Gilliam Autism Rating Scale/Gilliam Autism Rating Scale-Second Edition (GARS/GARS-2), Social Responsiveness Scale (SRS), Autism Spectrum Screening Questionnaire (ASSQ), and Asperger Syndrome Diagnostic Scale (ASDS). Twenty total studies were located, most examining the SCQ. Research on the other scales was limited. Comparisons between scales were few and available evidence of diagnostic validity is scarce for certain subpopulations (e.g., lower functioning individuals, PDDNOS). Overall, the SCQ performed well, the SRS and ASSQ showed promise, and the GARS/GARS-2 and ASDS demonstrated poor sensitivity. This review indicates that Level 2 ASD caregiver-completed rating scales are in need of much more scientific scrutiny.

The Autism Impact Measure (AIM) was designed to track incremental change in frequency and impact of core ASD symptoms. The current study examined the structural and convergent validity of the AIM in a large sample of children with ASD. The results of a series of exploratory and confirmatory factor analyses yielded a final model with five theoretically and empirically meaningful subdomains: Repetitive Behavior, Atypical Behavior, Communication, Social Reciprocity, and Peer Interaction. The final model showed very good fit both overall and for each of the five factors, indicating excellent structural validity. AIM subdomain scores were significantly correlated with measures of similar constructs across all five domains. The results provide further support for the psychometric properties of the AIM.

Youth with autism spectrum disorder (ASD) often present with emotional problems such as anxiety and depression (American Psychiatric Association, 2013). A recent study of the Child Behavior Checklist 6-18 (CBCL; Achenbach & Rescorla, 2001) indicated good sensitivity but relatively low specificity for identifying emotional problems in youth with ASD. The current study examined the extent to which variance in the CBCL's Anxious/Depressed, Withdrawn/Depressed, Internalizing Domain, and Total Problems scales was accounted for by symptoms of emotional problems relative to ASD symptoms. Correlation and multiple regression analyses indicated that these scales measured anxiety and depression but a small statistically significant proportion of variance in Total Problems scores was also accounted for by ASD symptoms. Results contribute to the emerging evidence base for the inclusion of the CBCL in assessment protocols for assessing emotional and behavioral problems in youth with ASD.