Psychometric properties of the Preschool Anxiety Scale in 2-6-year-old Chinese autistic children

Anxiety is a frequent comorbidity of autism spectrum disorder; however, early identification is hindered by a lack of validated assessment instruments for preschool autistic children. This study aims to evaluate the psychometric properties of the Preschool Anxiety Scale (PAS) in a large cohort of autistic toddlers and preschoolers, including its performance across demographic and clinical subgroups. We identified 905 Chinese autistic children (ages 2–6 years) enrolled in the Shanghai Autism Early Developmental study. Psychometric evaluation included internal consistency, construct validity, and convergent and divergent validity with the Strengths and Difficulties Questionnaire (SDQ) internalizing and externalizing scores, respectively. Subgroup analyses evaluated the stability of these measurements across age, sex, autistic symptom severity, and intellectual functioning and developmental status, and examined group differences in PAS scores. The PAS exhibited good internal consistency and acceptable convergent and divergent validity across the full sample (Cronbach’s alpha, 0.896; Pearson’s r, 0.278 with SDQ internalizing score, compared to 0.151 with SDQ externalizing score) and examined subgroups. While the original five-factor model exhibited suboptimal fit in a confirmatory factor analysis, an exploratory factor analysis supported a more parsimonious one- or two-factor structure, suggesting that anxiety symptoms may be less clearly differentiated by PAS within study population. These findings support the PAS as a reliable and valid tool for assessing anxiety symptoms in Chinese autistic preschoolers. The shift in factor structure from the original validation suggests future adaptation to this population. These insights can help in guiding interventions and understanding the anxiety profiles in Chinese young autistic children more effectively.