Sensitivity to change of the Quebec Back Pain Disability Scale and the Dallas Pain Questionnaire

Abstract

Objective To study and compare the sensitivities to change of the French versions of the Quebec Back Pain Disability Scale (QBPDS) and the Dallas Pain Questionnaire (DPQ). Method A retrospective study of the medical records of 30 chronic low back pain (LBP) outpatients undergoing a 4-week functional training program in a physical medicine and rehabilitation unit. Physical data (a visual analogue pain scale, the Schöber index, Sorensen and Shirado tests and the finger-to-floor distance) and functional status (QBPDS and DPQ scores) were measured at D0 and D25. Sensitivity to change was assessed in terms of the standardized response mean (SRM) and the effect size (ES). Results With the exception of the DPQ's “social interest” domain, all QBPDS and DPQ scores improved significantly over the course of the rehabilitation programme. Sensitivity to change was high for the QBPDS (SRM = 0.80; ES = 0.62) but only moderate for the DPQ (SRM = 0.59; ES = 0.61). Discussion-Conclusion Our results show that the QBPDS was more sensitive to clinical change than the DPQ in a sample of chronic LBP sufferers. It would be interesting to assess this sensitivity in a population of acute LBP patients and to evaluate the long-term effects of a functional rehabilitation program on the DPQ's “social interest” domain.