The Autism Mental Status Exam Indonesian Version(AMSE-INA): A Cross-Culturally Validated Pre-Diagnostic Tool for Autism Spectrum Disorder in Resource-Limited Specialist Settings

Background In many low and middle-income countries (LMICs), diagnosis of autism spectrum disorder (ASD) is hindered by limited access to gold-standard instruments, like the Autism Diagnostic Observation Schedule-2 (ADOS-2), due to cost, training, and licensing barriers. The Autism Mental Status Exam (AMSE) is a brief, observational tool designed to structure clinical observation and support diagnostic decision-making in specialist settings where comprehensive assessments are unavailable. Objective To adapt the AMSE into Indonesian (AMSE-INA) and validate it as a pre-diagnostic tool for use by specialists in secondary/tertiary care settings in Indonesia, where access to gold-standard instruments is constrained. Methods This cross-sectional diagnostic accuracy study comprised two phases: (1) rigorous cross-cultural adaptation following Beaton et al. guidelines, and (2) psychometric validation involving 174 children (aged 18 months–18 years) referred to a developmental specialist clinic. All participants underwent assessment with the AMSE-INA, the Indonesian version of the Childhood Autism Rating Scale-2 (CARS-2 ST), and a best-estimate clinical diagnosis (BECD) based on DSM-5 criteria by an experienced consultant blinded to AMSE scores. Reliability (internal consistency, inter-rater, test-retest), validity (content, concurrent, discriminant), and diagnostic accuracy (ROC analysis) were evaluated. Results AMSE-INA demonstrated excellent inter-rater reliability (ICC = 0.97) and test-retest reliability (ICC = 0.96). Internal consistency was moderate (α = 0.66), consistent with its multidimensional construct. Content validity was excellent (I-CVI = 1.00). Concurrent validity with CARS-2 ST was strong (r = 0.85, p < 0.001). ROC analysis revealed an AUC of 0.98 (95% CI: 0.96–1.00). A cut-off score of ≥6 provided optimal diagnostic utility for specialist settings: sensitivity 88.9%, specificity 94.7%, PPV 95.7%, NPV 86.6%. Conclusion AMSE-INA is a reliable, valid, and culturally appropriate pre-diagnostic tool that can assist specialists in establishing an accurate ASD diagnosis in resource-limited settings. By providing a structured observational framework, it bridges the diagnostic gap when gold-standard tools are inaccessible, improving early intervention access in Indonesia and similar settings.