Development and validation of knowledge, attitude, self-efficacy, and practice towards childhood autism spectrum disorder questionnaire (KASP-ASDQ) among primary care doctors

Primary care doctors (PCDs) play a key role in early identification of autism spectrum disorder (ASD). Knowledge, attitude, self-efficacy, and practice (KASP) towards childhood ASD in PCDs remain poorly understood, and validated tools to measure these domains are scarce. This study aimed to develop and validate a comprehensive questionnaire to measure the knowledge, attitude, self-efficacy, and practice towards childhood autism spectrum disorder (KASP-ASDQ). This study was conducted in two phases among PCDs. In Phase 1, content development team identified the construct of the questionnaire and items were generated using the deductive method based on literature review and existing tools. Phase 2a involved content validation by 7 expert panels and face validation by 10 PCDs. Phase 2b involved construct validity using exploratory factor analysis. Internal consistency was measured using Kuder-Richardson Formula 20 (KR-20) and Cronbach’s alpha, and test-retest reliability was evaluated using intraclass correlation coefficients (ICC) over 2–4 weeks period. Two items were removed after content validation due to low I-CVI scores. Face validation index for all items ranged from 0.80 to 1.00. Following validation, 70 items were constructed and underwent psychometric testing with 155 PCDs. Construct validity was carried out for the attitude, self-efficacy and practice domains. Items with factor loading ≤0.30 and some items with cross loadings were removed during EFA. Factor structures identified were three for attitude, two for self-efficacy, and three for practice. Item reduction yielded 64 items after construct validation. Ten items were removed from the knowledge domain producing moderate internal consistency with KR-20 of 0.5. Cronbach’s alpha values for attitude, self-efficacy and practice domains were 0.74, 0.94 and 0.89 respectively. Most items showed good to excellent test-retest reliability (ICC ≥ 0.60). The final 54-item KASP-ASDQ demonstrated satisfactory validity and reliability for assessing the level of knowledge, attitude, self-efficacy and practice towards childhood ASD among PCDs doctors in Malaysia.