Reliability and validity of the Turkish version of Post-COVID-19 Functional Status Scale

Background/aim: The post-COVID-19 Functional Status (PCFS) has recently been developed for functional outcomes of COVID-19 upon discharge and in long term. The purpose of this study was to investigate the reliability and validity properties of the Turkish version of the PCFS in Turkish post-COVID-19 patients with hospitalized and nonhospitalized during infection. Materials and methods: One hundred participants with post-COVID-19 were included in this cross-sectional study. Test-retest reliability of the Turkish version of PCFS assessed by intraclass correlation coefficient (ICC) and Cronbach's alpha was calculated for internal consistency. For construct validity, correlation coefficients between the Turkish version of PCFS developed by translation-back translation method and modified Medical Research Council (mMRC) dyspnea scale (MMRC), London Chest Activities of Daily Living (LCADL) scale, Barthel Index (BI) were analyzed. Results: For test-retest reliability analysis, ICC ranged between 0.734 and 0.880. The total ICC score was 0.821, indicating excellent reliability. The Cronbach's alpha value of the PCFS test and retest scores were recorded as 0.821 indicating that the scale is quite reliable. The PCFS score was moderately correlated with the mMRC score (r = 0.534, p < 0.001) and weakly correlated with the LCADL self care (r = 0.311, p = 0.002), domestic (r = 0.277, p = 0.005), physical activity (r = 0.342, p < 0.001), leisure subscores (r = 0.434, p < 0.001) and total score (r = 0.399, p < 0.001). Conclusion: The Turkish version of the PCFS scale is reliable scale that reflects activity limitation and functional status after COVID-19. The Turkish version of the PCFS will be a guide for rehabilitation professionals to understand functional limitation after COVID-19 and to direct interventions accordingly to functional status of the patients at discharge and in long term.