Hindi translation and validation of Cambridge-Hopkins Diagnostic Questionnaire for RLS (CHRLSq)

BACKGROUND: Restless legs syndrome also known as Willis-Ekbom's Disease (RLS/WED) is a common illness. Cambridge-Hopkins diagnostic questionnaire for RLS (CHRLSq) is a good diagnostic tool and can be used in the epidemiological studies. However, its Hindi version is not available. Thus, this study was conducted to translate and validate it in the Hindi speaking population. MATERIALS AND METHODS: After obtaining the permission from the author of the CHRLSq, it was translated into Hindi language by two independent translators. After a series of forward and back translations, the finalized Hindi version was administered to two groups by one of the authors, who were blinded to the clinical diagnosis. First group consisted of RLS/WED patients, where diagnosis was made upon face to face interview and the other group — the control group included subjects with somatic symptoms disorders or exertional myalgia or chronic insomnia. Each group had 30 subjects. Diagnosis made on CHRLSq was compared with the clinical diagnosis. STATISTICAL ANALYSIS: Analysis was done using Statistical Package for Social Sciences (SPSS) v 21.0. Descriptive statistics was calculated. Proportions were compared using chi-square test; whereas, categorical variables were compared using independent sample t-test. Sensitivity, specificity, and positive predictive value of the translated version of questionnaire were calculated. RESULTS: Average age was comparable between the cases and control group (RLS/WED = 39.1 ± 10.1 years vs 36.2 ± 11.4 years in controls; P = 0.29). Women outnumbered men in the RLS/WED group (87% in RLS/WED group vs 57% among controls; χ(2) = 6.64; P = 0.01). Both the sensitivity and specificity of the translated version was 83.3%. It had the positive predictive value of 86.6%. CONCLUSION: Hindi version of CHRLSq has positive predictive value of 87% and it can be used to diagnose RLS in Hindi speaking population.