Reliability, Validity, and Sensitivity Measures of Expanded and Revised Version of the Short-Form McGill Pain Questionnaire (SF-MPQ-2) in Iranian Patients with Neuropathic and Non-Neuropathic Pain

Abstract

The aim of this study was to assess validity, reliability, and sensitivity of the Persian version of the short-form McGill Pain Questionnaire 2 (SF-MPQ-2) in patients with neuropathic and non-neuropathic pain. Beaton's guideline was used to translate and adapt the SF-MPQ-2 to Persian. One hundred eighty-four patients with subacute and chronic non-neuropathic pain and 74 patients with painful diabetic peripheral neuropathy (total 258) attending multidisciplinary pain clinic participated in the study. Internal consistency and intraclass correlation coefficient (ICC) were estimated for participants who had completed the questionnaire in the morning and evening of the first day. The visual analog scale (VAS) and the present pain intensity (PPI) were also recorded to test convergent validity of the questionnaire. Sensitivity to change was examined after a standard treatment and validated by means of the patient global impression of change (PGIC) in addition to VAS and PPI. Exploratory factor analysis (EFA) was used to find possible components. Cronbach's alpha was 0.906, which showed high internal consistency. ICC (0.941) revealed test-retest reliability. There was high correlation between the mean VAS and the mean total score (r = 0.926). Patients in different levels of PPI and PGIC exhibited significant differences among their mean total scores (P < 0.05). EFA revealed four components similar to the original SF-MPQ-2. The Persian translation of the expanded and revised version of the SF-MPQ-2 is a highly reliable, sensitive, and valid instrument to evaluate pain in patients with and without neuropathic etiology.