Questionnaires are widely used in autism assessment. However, their psychometric properties are generally not evaluated in clinical practice, and the comparability and applicability of such research is limited because questionnaires are often not simultaneously evaluated. This certainly pertains to predictive values which are highly population and setting specific. This study evaluated the power of AQ and SRS-A in predicting an ASD diagnosis within the same clinical population. The patient records of 92 adults, referred for autism assessment, were analyzed. The AQ proved somewhat better than the SRS-A at discriminating and predicting autism. The predictive values of both questionnaires were lower than reported in general population studies. Psychometric results in core publications appear less representative for clinical practice.
Keywords: AQ; ASD; Predictive value; SRS-A.