Validation of Persian Multiple Sclerosis quality of life-29 (P-MSQOL-29) questionnaire

Multiple sclerosis (MS) is the most prevalent neurological disease among young adults. Because of the chronic nature of this disease, it is important to assess quality of life in these patients. The Multiple Sclerosis Quality of Life -29 (MSQOL-29) questionnaire which contains two main scales, Physical Health Composite (PHC) and Mental Health Composite (MHC), has been designed for this goal. The purpose of the present study is to translate and validate a Persian version of MSQOL-29 (P-MSQOL-29).

Using the forward-backward translation method, a panel of experts established the content validity of P-MSQOL-29. It was then administered to 100 patients with MS who also completed the Short Form-12 (SF-12) questionnaire. Cronbach's alpha was used to assess the internal consistency of P-MSQOL-29. Spearman's correlation coefficient was used to analyze the concurrent validity when correlating the items of P-MSQOL-29 to SF-12.

Mean (Standard Deviation) of PHC and MHC for all patients was 51 (16.4), and 58 (23), respectively. Cronbach's alpha was 0.7 for PHC and 0.9 for MHC. Thirty patients completed the questionnaire again after 3-4 weeks, Intraclass Correlation Coeffiecient (ICC) was 0.80 for PHCs and 0.85 for MHCs (both P values < 0.01). A moderate to high correlation was detected between MHC/PHC and the corresponding scales of SF-12 (MHC with Mental Component Score: ρ = 0.55; PHC with Physical Component Score: ρ = 0.77; both P values < 0.01).

P-MSQOL-29 is a valid and reliable questionnaire and can be used for assessing quality of life in patients with MS.