Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) Validation in Portugal: Preliminary Results

Background: Autism Spectrum Disorders (ASD) are lifelong developmental disorders, and early intervention is crucial for positive outcomes. ASD early screening in low-risk samples has been recommended as a strategy to promote early diagnosis, which facilitates early intervention. Screening procedures in Portugal are not yet common, which delays detection for many children. In order to increase ASD screening, a study using the Modified Checklist for Autism in Toddlers, Revised (M-CHAT-R) has been implemented in pediatric and childcare settings.

Objectives: The main goal of this study is to establish preliminary validity for the M-CHAT-R in Portugal as a screening tool for low-risk toddlers.

Methods: Toddlers are recruited from two sources: childcare centers and pediatric check-ups. To date, 563 toddlers between 15 and 31 months (m=22.84, SD=4.23) were screened with M-CHAT-R. Parents of toddlers at risk on M-CHAT-R completed the M-CHAT-R Follow-up as an interview, and those who continued to show risk completed an evaluation using Autism Diagnostic Observation Schedule (ADOS), Autism Diagnostic Interview Revised (ADI-R), and Griffiths Mental Development Scale.

Results: Pediatric providers were reluctant to join the study. The majority of participants (80%) were screened in the daycare setting. From the 451 screened in daycare, 41 were positive (9.1%). After the Follow-up, eight continued to screen positive and four were diagnosed with an ASD, two had other developmental delays, and two were typically developing. From the 112 toddlers screened in pediatricians’ settings, ten were positive (8.9%), after the Follow-up three continued to screen positive; one was diagnosed with ASD, one had a developmental delay, and one was typically developing. In both groups, the prevalence of ASD detected was 1 in 112.

Conclusions: Professionals from daycares were more receptive to screen for ASD than pediatricians during check-ups. Across the two groups, the M-CHAT-R performed similarly (9.1 vs 8.9% screened positive initially, similar ASD rate detected), suggesting that the setting does not impact the performance of the screening tool. ASD rates were consistent with other screening studies (Robins et al., 2014). Given the reluctance of many pediatric providers to incorporate routine ASD screening into well-child check-ups, daycare is a viable alternate setting. Portugal continues to require more information and awareness about ASD screening as an essential way to detect ASD and start early intervention as young as possible in order to improve children’s outcomes. Additional education for pediatric providers may help doctors understand the value of ASD screening in low-risk samples.