Concurrent validity of the ages and stages questionnaires with Bayley Scales of Infant Development-III at 2 years – Singapore cohort study

Background: With increasing acceptance of universal developmental screening in primary care, it is essential to evaluate the local validity and psychometric properties of commonly used questionnaires like the parent-completed Ages and Stages Questionnaires, 3rd Edition (ASQ-3) in identifying developmental delays. The aim of this study is to assess the convergent validity of the ASQ-3 with the Bayley Scales of Infant Development-3rd edition (Bayley-III) in identifying developmental delay in a low-risk term cohort in Singapore. Methods: ASQ-3 and Bayley-III data was collected prospectively with generation of ASQ-3 cut-off scores using three different criteria: 1-standard deviation (SD) (Criterion-I) or 2-SD (Criterion-II) below the mean, and using a Receiver Operator Curve (ROC) (Criterion-III). Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were calculated. Correlations between the ASQ-3 and Bayley-III domains were evaluated using Pearson coefficients. Results: With all three criteria across different domains ASQ-3 showed high specificity (72–99%) and NPV (69–98%), but lower sensitivity (19–74%) and PPV (11–59%). Criterion-I identified 11–21% of children as “at-risk of developmental delay,” and was the most promising criterion measure, with high specificity (82–91%), NPV (69–74%) and overall agreement of 64–71%. Moderate-strong correlations were seen between ASQ-3 Communication and Bayley-III Language scales (r = 0.44–0.59, p