Meta-analysis of the Modified Checklist for Autism in Toddlers, Revised/Follow-up for Screening.

Researchers reviewed studies of the M-CHAT-R/F autism screening questionnaire used with toddlers. They found the tool correctly identifies about 83% of children who have autism. However, when a child screens positive, there's only about a 58% chance they'll actually be diagnosed with autism - this increases to 76% for high-risk children. The tool is useful for screening but families should understand that a positive result doesn't guarantee an autism diagnosis and further assessment is needed.

This meta-analysis examined the accuracy of the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) screening tool across 15 studies involving 49,841 children from 10 countries. The tool demonstrated moderate effectiveness with a positive predictive value of 57.7%, meaning approximately 58% of children who screen positive actually receive an ASD diagnosis. The tool showed higher accuracy in high-risk populations (75.6% PPV) compared to general population screening (51.2% PPV). Sensitivity was good at 82.6%, indicating the tool successfully identifies most children with autism, though specificity was lower at 45.7%.

The findings support continued use of M-CHAT-R/F for autism screening while emphasizing the need for appropriate counseling about diagnostic likelihood following positive screens.

M-CHAT-R/F remains a valuable autism screening tool, particularly for high-risk populations. Clinicians should counsel families that positive screens require diagnostic follow-up, with approximately 6 in 10 positive screens leading to autism diagnosis. The tool's high sensitivity supports its use for early identification while moderate positive predictive value necessitates careful communication about diagnostic likelihood.

Analysis was limited by small sample sizes for calculating negative predictive value, sensitivity, and specificity due to limited evaluation of screen-negative children. Between-study heterogeneity was present, and the analysis relied on studies with varying methodological quality.

The Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) is used worldwide to screen for autism spectrum disorder (ASD). To calculate psychometric properties of the M-CHAT-R/F for subsequent diagnosis of ASD. Systematic searches of Medline, Embase, SCOPUS, and Trip Pro databases from January 2014 to November 2021. Studies were included if they (1) used the M-CHAT-R/F (2) applied standard scoring protocol, (3) used a diagnostic assessment for ASD, and (4) reported at least 1 psychometric property of the M-CHAT-R/F.

Two independent reviewers completed screening, full-text review, data extraction, and quality assessment, following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. A random-effects model was used to derive pooled estimates and assess for between-study heterogeneity. Of 667 studies identified, 15 with 18 distinct samples from 10 countries (49 841 children) were used in the meta-analysis. Pooled positive predictive value (PPV), was 57.7% (95% confidence interval [CI] 48.6-66.8, τ2 = 0.031).

PPV was higher among high-risk (75.6% [95% CI 66.0-85.2]) than low-risk samples (51.2% [95% CI 43.0-59.5]). Pooled negative predictive value was 72.5% (95% CI 62.5-82.4 τ2 = 0.031), sensitivity was 82.6% (95% CI 76.2-88.9) and specificity 45.7% (95% CI 25.0-66.4). Negative predictive value, sensitivity, and specificity were calculated based on small sample sizes because of limited or no evaluation of screen-negative children. These results support use of the M-CHAT-R/F as a screening tool for ASD.

Caregiver counseling regarding likelihood of an ASD diagnosis after positive screen should acknowledge the moderate PPV.