INTRODUCTION: Screening for Autism Spectrum Disorders (ASD) using the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) increases early detection, allowing early interventions and improving prognosis. This tool is part of the management in case of suspected ASD in several clinical guidelines. The objective of this article was to conduct the concurrent and discrimi nant validation and the reliability analysis of M-CHAT-R/F in the Chilean population. PATIENTS AND METHOD: This is the second stage of the cross-cultural adaptation of cross-sectional design. M-CHAT- R/F was applied to a sample of 20 children with suspected ASD and 100 randomly selected healthy control children, aged between 16-30 months. Autism Diagnostic Observation Schedule (ADOS-2), considered as reference, was applied to the 20 patients of the clinical sample, to 20 children of the healthy control sample and to those cases of the healthy control sample with M-CHAT-R/F positive. Cronbach alpha was calculated, as well as M-CHAT-R/F and ADOS-2 correlation, sensitivity, and specificity analyses. RESULTS: In the healthy sample, M-CHAT-R/F was positive in two patients, with one of them positive and the other one negative for ASD with ADOS-2 test. In the clinical sample, M- CHAT-R/F was positive in all cases, three of them were negative in the ADOS-2 test. The Alfa relia bility of M-CHART-R/T was 0,889, the discriminant sensitivity and specificity were 100% and 98%, and the concurrent ones were 100% and 87.5% respectively. CONCLUSIONS: The Chilean M-CHAT- R/F version was reliable, sensitive and specific, similar to the original test, which opens the possibility for its use in clinical samples and for research. Validating M-CHAT-R/F is an ongoing process which must be further developed.
INTRODUCTION: Screening for Autism Spectrum Disorders (ASD) using the Modified Checklist for Autism in Toddlers, Revised with Follow-up (M-CHAT-R/F) increases early detection, allowing early interventions and improving prognosis. This tool is part of the management in case of suspected ASD in several clinical guidelines. The objective of this article was to conduct the concurrent and discrimi nant validation and the reliability analysis of M-CHAT-R/F in the Chilean population. PATIENTS AND METHOD: This is the second stage of the cross-cultural adaptation of cross-sectional design. M-CHAT- R/F was applied to a sample of 20 children with suspected ASD and 100 randomly selected healthy control children, aged between 16-30 months. Autism Diagnostic Observation Schedule (ADOS-2), considered as reference, was applied to the 20 patients of the clinical sample, to 20 children of the healthy control sample and to those cases of the healthy control sample with M-CHAT-R/F positive. Cronbach alpha was calculated, as well as M-CHAT-R/F and ADOS-2 correlation, sensitivity, and specificity analyses. RESULTS: In the healthy sample, M-CHAT-R/F was positive in two patients, with one of them positive and the other one negative for ASD with ADOS-2 test. In the clinical sample, M- CHAT-R/F was positive in all cases, three of them were negative in the ADOS-2 test. The Alfa relia bility of M-CHART-R/T was 0,889, the discriminant sensitivity and specificity were 100% and 98%, and the concurrent ones were 100% and 87.5% respectively. CONCLUSIONS: The Chilean M-CHAT- R/F version was reliable, sensitive and specific, similar to the original test, which opens the possibility for its use in clinical samples and for research. Validating M-CHAT-R/F is an ongoing process which must be further developed.