Validity and reliability of the Turkish version of the Ottawa Sitting Scale in patients with acute stroke

Purpose: To investigate the validity and reliability of the Turkish version of the Ottawa Sitting Scale (OSS-T) in patients with acute stroke.Materials and methods: The Berg Balance Scale (BBS) and Trunk Impairment Scale (TIS) were used to determine the validity of the OSS-T. The OSS-T was re-applied by the same rater after an interval of 7 days to determine the reliability. To test inter-rater reliability, the evaluation was repeated by a second rater 1 day after the first evaluation. Reliability was quantified using intraclass correlation coefficients (ICC), and validity was assessed by correlating the OSS-T scores with the results of the other measures.Results: The ICC of the total OSS-T score for inter-rater reliability was 0.996 and for intra-rater reliability, it was 0.951. The Cronbach's a coefficient used to determine internal consistency was 0.980, which indicates excellent reliability. A strong positive correlation was found between OSS-T and TIS (rho = 0.861, p < 0.001), and between OSS-T and BBS (rho = 0.875, p < 0.001). An evident 2-factor structure was shown by the results of the factor analysis.Conclusions: The results of this study indicated that the OSS-T has strong measurement properties, making it a valid and reliable tool for research and clinical practice in patients with acute stroke.