Reliability, Responsiveness, and Interpretability of the Participation Questionnaire for Preschoolers with Autism Spectrum Disorder

This cohort study aimed to evaluate the test–retest reliability, responsiveness, and interpretability of the Participation Questionnaire for Preschoolers (PQP), a tool for assessing participation in preschool children with autism spectrum disorder (ASD). Caregivers of children with ASD aged 51–75 months completed online surveys at four time points over six months. Test–retest reliability was examined using intraclass correlation coefficients (ICCs) for 275 participants. Responsiveness was examined by analyzing correlations between changes in PQP scores and the Strengths and Difficulties Questionnaire and the Family Outcomes Survey based on four predefined hypotheses. To assess interpretability, the Global Rating of Change (GRC) Scale was used as an anchor to analyze receiver operating characteristic curves and estimate minimal important change (MIC). ICCs ranged from 0.80 to 0.92 for individual subscales and reached 0.93 for the total score. Three of four hypotheses for responsiveness were supported. However, the correlation between the GRC Scale and changes in PQP scores was below 0.3, preventing MIC calculation. Although the MIC could not be calculated, the PQP’s strong test–retest reliability and responsiveness provide a foundation for future research.