Systematic review of clinical guidance documents for autism spectrum disorder diagnostic assessment in select regions.

Only 11 guidance documents met inclusion criteria. The search was limited to English documents from Canadian, American and UK professional associations and English-speaking single-payer government systems. Screening, full-text review and content analysis were done by one reviewer, not independently by two. The review examined guideline quality and content, not diagnostic accuracy in patients. Two included documents were no longer endorsed: the 2001 AAP document was replaced in 2007, and the ASHA guideline was rescinded in 2015. Wait time recommendations were given without supporting evidence or clear consensus. The review did not cover all testing involved in ASD diagnosis, such as genetic testing, because it did not influence service eligibility.

The authors declared no competing interests for Penner, Ungar and Andoni. Dr Anagnostou served as a consultant to Roche, received grant funding from Sanofi Canada and SynapDx, received royalties from APPI and Springer, and received kind support from AMO Pharmaceuticals. Melanie Penner received salary funding from the Clinician Investigator Program at the University of Toronto, a Canada Graduate Scholarship, and a salary award from the Department of Paediatrics at the University of Toronto. The named funder was the University of Toronto Faculty of Medicine.

Do not read the broad support for multidisciplinary team assessment as proof that team diagnosis is more accurate than solo diagnosis. The review found little to no empirical evidence that team assessment is more accurate than solo assessment.