Validation of a modified McGill Pain Questionnaire for orthodontic patients

Objective: To assess better and more efficiently the aspects of pain experienced by adolescent orthodontic patients, the McGill Pain Questionnaire-Short Form (MPQ-SF) was modified (MMPQSF) and validated. Materials and Methods: Internal and external expert panels developed a MMPQ-SF with 15 descriptors and 4-point Likert severity scales (MMPQ-SF15). Seventy-five subjects undergoing orthodontic treatment gave informed consent. Sixty-one subjects completed the MMPQ-SF15, a visual analogue scale (VAS), and the present pain index (PPI) 24 hours after an orthodontic visit. Respondents were grouped by gender and treatment stage: initial (15 female, 7 male), middle (10 female, 7 male), and end (16 female, 6 male). MMPQ-SF, VAS, and PPI scores were compared by Spearman correlation analysis. Underlying constructs were explored by factor analyses. Construct validity of the MMPQ-SF was tested by analysis of variance. Results: MMPQ-SF15 and VAS (r = 0.78, r² _s = 0.61, P < .0001), MMPQ-SF15 and PPI (r = 0.84, r² _s = 0.71, P < .0001), and VAS and PPI (r = 0.70, r² _s = 0.48, P < .0001) were correlated positively and significantly. A two-factor solution (localized and generalized/emotional pain; Kaiser- Meyer-Olkin = 0.88) showed that 11 descriptors (MMPQ-SF11) accounted for 64% of response variability. Generalized/emotional pain values were significantly higher during the initial stage of treatment compared to the middle (P = .011) and end stages (P = .014). Conclusions: MMPQ-SF, particularly MMPQ-SF11, demonstrated utility in assessment of localized and generalized/emotional aspects of pain in adolescent orthodontic patients and correlated well with VAS and PPI. Future application of the MMPQ-SF11 to measure orthodontic pain more specifically could lead to more appropriate management of this important facet of therapy. (Angle Orthod. 2013;83:906-912.)