Study of M-CHAT Psychometric Proprieties in Brazil

Abstract

This study aims to assess the psychometric properties of the instrument Modified Checklist for Autism in Toddlers (M-CHAT) in children from 24 to 36 months old with (Group 1/n = 88) and without (Group 2/n = 1116) Autism Spectrum Disorder (ASD). Internal consistency was evaluated and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were estimated. Also, the Receiver Operating Characteristic (ROC) curve was generated. To evaluate the discriminant validity, the proportion of flaws among children with and without ASD was assessed by applying the Chi-square test or by the Exact Fisher test. The number of flaws based on sex, age group, and participant’s group was also compared with the Mann-Whitney Test. The M-CHAT showed high internal consistency (0.78 and 0.86), satisfactory reproductivity (Kappa 0.60 and 0.79 and ICC = 0.87 and 0.89), high sensibility (0.807 and 0.932), specificity (0.927 and 0.706), and NPV (0.984 and 0.992); however, PPV estimates (0.467 and 0.250) were not satisfactory. Regarding the discriminant validity, the proportion of flaws was significantly higher in the group of children with ASD. Moreover, the number of flaws was larger among boys, in the age group 25-36 months, and in the group with ASD. The Brazilian version of M-CHAT has adequate psychometric properties concerning reliability, sensitivity, specificity, NPV and discriminant validity, which makes its application recommendable to track children with ASD signs.

Keywords:
Autism Spectrum Disorder; Validation Studies; Screening; Sensitivity; Specificity