Validation and determining an optimal cut-off score of the Infant Behavior Checklist for autism spectrum disorder.

Aim: Given the escalating prevalence of autism spectrum disorder (ASD), the persistent paucity of child psychiatrists in Japan, and the need to prepare for unforeseen situations, such as the COVID-19 pandemic, it is essential to establish a reliable screening tool. This study aims to validate the Infant Behavior Checklist (IBC) developed by Japanese experts and determine its appropriate cut-off score.

Methods: A total of 354 clinic-referred children, along with their caregivers, participated in this research.