Validation of the Thai version of the modified social functioning scale (SFS) for individuals with schizophrenia

The Social Functioning Scale (SFS) is widely used to evaluate social functioning in individuals with schizophrenia. While validated in various cultural contexts, adaptation for Thailand is necessary to address cultural and contextual nuances. This study aimed to translate and culturally adapt the SFS into Thai and assess its reliability and validity.

A sample of 109 individuals (52.3% female) diagnosed with schizophrenia was recruited from a university hospital in Thailand. Exploratory Factor Analysis (EFA) and reliability tests were conducted on six subscales of the Modified SFS- Thai version. Concurrent validity was assessed using the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), Social and Occupational Functioning Assessment Scale (SOFAS), Scale for the Assessment of Positive Symptoms (SAPS), and Scale for the Assessment of Negative Symptoms (SANS).

EFA of four subscales-Independence Performance, Recreation, Pro-Social, and Independence Competence-revealed distinct factor structures with strong loadings. The Employment and Withdrawal/Interpersonal subscales could not undergo EFA due to binary items and insufficient sampling adequacy. Cronbach's alpha values of the modified subscales ranged from 0.75 to 0.87, indicating good internal consistency. Significant correlations with WHODAS 2.0, SOFAS, SAPS, and SANS confirmed the scale's validity.

The Modified SFS- Thai version is a reliable and valid tool for assessing social functioning in individuals with schizophrenia. Its cultural adaptation enhances its relevance in Southeast Asia, offering valuable insights for clinical practice and research in low- and middle-income countries.