Cultural adaptation, translation and validation of Cochin Hand Function Scale and evaluation of hand dysfunction in systemic sclerosis

Objectives Hand dysfunction causes significant reduction in quality of life in systemic sclerosis. We assessed the validity and reliability of the culturally adapted Indian version of Cochin Hand Function Scale (I-CHFS). We determined the factors contributing to hand dysfunction and its burden on quality of life. Method I-CHFS was formulated by replacing five questions (questions 7, 9, 10, 14 and 15) in CHFS which were determined as unsuitable in an Indian setting. The instrument was assessed for acceptability, reliability, reproducibility and validity measures. A total of 87 patients were assessed for various demographic and disease parameters, hand disability and quality of life. Results The median I-CHFS score was 22(5-54) and 04 (0.5-17.5) among diffuse (dcSSc) and limited cutaneous systemic sclerosis (lcSSc). I-CHFS showed good reproducibility (interclass correlation coefficient = 0.92) and a strong correlation with I-HAQ (r(s) = 0.832), usual activities EQ-5D-5L (r(s) = 0.744), self-care EQ-5D-5L (r(s) = 0.734) and anxiety/depression EQ-5D-5L (r(s) = 0.729). It had moderate correlation with pain/discomfort EQ-5D-5L (r(s) = 0.661) and hand HAQ (r(s) = 0.576) and poor correlation with HAQ-DI (r(s) = 0.396) and modified Rodnan skin score (r(s) = 0.390). Finger to table distance, finger to palm distance in extension and limited hand modified Rodnan skin score were significantly associated with higher values of I-CHFS. Conclusions Hand dysfunction in systemic sclerosis is substantial and contributes significantly to poor quality of life. The culturally adapted I-CHFS is a valid and reliable tool to assess it and correlated well with the overall disease burden.