Diagnostic Tests for Autism in Preschool Children: A Review Protocol

In one sentence

This Cochrane protocol outlines a planned systematic review to evaluate how accurate widely used diagnostic tools (like ADOS and ADI-R) are for identifying autism in preschool children, compared to a team of experienced clinicians.

What the researchers did

The researchers designed a protocol for a Cochrane diagnostic test accuracy review. They plan to search for studies that test one or more of six common autism diagnostic tools (CARS, GARS, ADOS, ADI-R, DISCO, 3di) in children under age 6. The reference standard (the best available method to confirm the diagnosis) will be a multidisciplinary team clinical judgment. They will calculate sensitivity (how well the test catches true cases) and specificity (how well it rules out non-cases). They also plan to look at whether combining tools improves accuracy, and whether accuracy differs for subgroups like children with intellectual disability or different language levels.

What they found

• This is a protocol, so no results are reported yet. The review is planned but not completed.
• The researchers specify that they will include studies of any design that compare a diagnostic tool to multidisciplinary team clinical judgment.
• They will assess risk of bias using the QUADAS-2 tool (a standard checklist for diagnostic studies).
• They will summarize sensitivity and specificity for each tool, and for combinations of tools, using meta-analysis if possible.

What this means for families and therapists

• For parents: When your child is evaluated for autism, the clinician may use one or more standardized tools. This review will help clarify how reliable those tools are for preschool-aged children.
• For therapists: If you are involved in diagnostic assessments, this review may guide which tools to use and whether combining them adds value.
• For both: The review will also explore whether tools work differently for children with additional conditions like intellectual disability, which can inform more tailored assessments.

Limitations and what we don't know yet

• This is only a protocol — the actual review has not been conducted. No conclusions can be drawn yet.
• The planned review will depend on the quality and quantity of available studies, which may be limited.
• The reference standard (multidisciplinary team judgment) is itself not perfect and may vary across settings.
• The review will only cover preschool children, so findings may not apply to older children or adults.

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This is a plain-language summary of Diagnostic Tests for Autism in Preschool Children: A Review Protocol by Brignell A, Chan K, Chellew T, Maddumahewa C.V et al., Cochrane Database of Systematic Reviews (2026). Source license: CC-BY-NC-4.0. It is not medical advice — talk to a qualified clinician before changing therapy.