Autism screening questionnaire: Diagnostic validity

TLDR

Good interview and diagnostic measures for autism and other pervasive developmental disorders (PDDs) are available but there is a lack of a good screening questionnaire. The study aimed to develop and test a screening questionnaire based on items from the Autism Diagnostic Interview–Revised. A 40‑item Autism Screening Questionnaire (ASQ) was created and evaluated on 160 PDD and 40 non‑PDD participants. The ASQ demonstrated strong discriminative validity between PDD and non‑PDD across all IQ levels, with a cut‑off of 15 most effective, though it was less able to distinguish autism from other PDD subtypes, confirming its overall effectiveness as a screening tool.

Abstract

Background Good interview and diagnostic measures for autism and other pervasive developmental disorders (PDDs) are available but there is a lack of a good screening questionnaire. Aims To develop and test a screening questionnaire based on items in the best available diagnostic interview – the Autism Diagnostic Interview – Revised (ADI–R) Method A 40 -item scale, the Autism Screening Questionnaire (ASQ), was developed and tested on a sample of 160 individuals with PDD and 40 with non-PDD diagnoses. Results The ASQ has good discriminative validity with respect to the separation of PDD from non-PDD diagnoses at all IQ levels, with a cut-off of 15 proving most effective. The differentiation between autism and other varieties of PDD was weaker. Conclusions The ASQ is an effective screening questionnaire for PDD.