Primary care providers can effectively conduct the follow-up interview after a positive screening on the Modified Checklist for Autism in Toddlers (M-CHAT) without missing cases or flagging too many false positives, suggests a recent study.
“The online M-CHAT/F [M-CHAT Follow-up Interview] enabled PCPs [primary care providers] to clarify positive parent responses to M-CHAT items during well-child visits, rather than requiring another visit or call by a trained interviewer,” wrote Raymond Sturner, MD, of Johns Hopkins University, Baltimore, and his colleagues.
“This study found that the performance of the M-CHAT/F by a PCP was equivalent to one administered by trained Kennedy Krieger Institute Center for Autism and Related Disorders staff,” they wrote (Pediatrics. 2016 Aug 19. doi: 10.1542/peds.2015-3036). “This report is the first demonstrating feasibility of administration of the M-CHAT/F during the time of well-child visit in community practices.”
The authors recruited 47 primary care providers at 22 clinics in Maryland to complete an M-CHAT/F during children’s 18- and 24-month routine visits if their initial M-CHAT yielded a positive screening. Each family was then contacted again for an M-CHAT/F conducted by a trained research assistant from the Kennedy Krieger Institute Center for Autism and Related Disorders.
The PCPs volunteered for the study and primarily had suburban practices, with just 18% rural and 9% urban practices. Just under a third of children at the practices were insured by Medicaid, and the demographic breakdown included 39% white, 33% African-American, 16% Asian, and 8% Hispanic.
Of the 5,071 children screened (mean age, 23 months), 6.7% had a positive screen. Of the 197 M-CHAT/Fs the PCPs completed, 99 children then underwent a full autism spectrum disorder (ASD) diagnostic evaluation, including administration of the Autism Diagnostic Observation Schedule and the Mullen Scales of Early Learning .
PCPs and research assistants agreed 86.6% of the time on the result of the M-CHAT/F screening, with statistically equivalent positive predictive value (PPV), sensitivity, specificity, and overall accuracy. The research assistants’ PPV was 0.84, and the PCPs’ PPV was 0.88. The PPV for any developmental delay diagnosis was similarly equivalent between the research assistants and PCPs.
Dr. Sturner and his associates noted that the findings confirm “previous studies showing that most children with false-positive screens have developmental difficulties of a degree that would make them eligible for early intervention. Some children with false-positive screens had atypical features not meeting criteria for ASD.”
The National Institutes of Mental Health funded the research. Dr. Sturner is director of Total Child Health (TCH), a for-profit subsidiary of the Center for Promotion of Child Development through Primary Care, which conducted the study. Barbara Howard, MD, is president of TCH. Tanya Morrel, PhD, is an employee of and stockholder in TCH, and Paul Bergmann has consulted for the company. The remaining authors had no relevant disclosures.