Psychometric properties of the Thai version of Allen Cognitive Level Screen-5 (Thai ACLS-5) for individuals with schizophrenia

Background: Cognitive impairment is a critical concern for individuals with schizophrenia, affecting their occupational performance, daily activities, and the potential for rehabilitation and skill development. The Allen Cognitive Level Screen-5 (ACLS-5) is a standardized, performance-based assessment designed to evaluate functional cognitive abilities and limitations, providing guidance for individualized interventions. However, there is currently no Thai translation for the ACLS-5. Objectives: This study aimed to translate the ACLS-5 into Thai using a back-translation method and to evaluate its psychometric properties, focusing on construct validity and inter-rater reliability, to ensure its suitability for use in Thai clinical settings. Materials and methods: The ACLS-5 was translated from English into Thai following Beaton’s protocol, a five-step process for cross-cultural adaptation, and the pre-final version was tested on a sample of 30 individuals with schizophrenia to assess cultural adaptation and content validity. Construct validity was evaluated using a sample of 102 participants, comprising of 51 individuals with schizophrenia and 51 healthy individuals. Inter-rater reliability was examined by two occupational therapists who independently evaluated 38 participants from the schizophrenia group. Results: In the translation and cultural adaptation phase, the names of the stitching tasks were modified to match Thai culture. Feedback from the Allen Cognitive Group suggested that the terms lacked direct Thai equivalents; consequently, they remained in their original English form. The pre-final Thai ACLS-5 was tested with 30 individuals with schizophrenia, in which it was reported that the instructions were clear and easy to understand. The Mann-Whitney U test indicated a significant difference in construct validity between individuals with schizophrenia and healthy controls (Z=-6.511, p<0.000), confirming the assessment’s effectiveness in distinguishing cognitive impairment. The intraclass correlation coefficient (ICC) for inter-rater reliability was 0.932, demonstrating excellent reliability. Conclusion: These findings confirm that the Thai ACLS-5 is a valid and reliable assessment for evaluating functional cognition in individuals with schizophrenia. It allows for a quick and effective assessment of functional cognition in clinical settings. Future research should examine usage in different populations to further establish its utilization.