Abstract
BACKGROUND: Multidisciplinary pain management programs based on cognitive behavioral training (CBT) principles have been shown moderately effective in improving daily functioning in patients with chronic low back pain (CLBP). To optimize health-related outcomes as daily functioning, a clear understanding of the working mechanisms of these programs is warranted. Being confident to achieve a desired outcome, i.e. self-efficacy, is suggested to be a more potent determinant for beneficial treatment outcomes than restructuring the patient's dysfunctional behavioral cognitions (pain catastrophizing and fear of movement [FoM]), but the evidence is scarce. The objective of this study was twofold: 1) to determine whether a two-week pain management program resulted in post-treatment improvements in self-efficacy and decreased dysfunctional behavioral cognitions in patients with CLBP, and 2) to examine the unique contribution of self-efficacy to improvement in post-treatment disability. METHODS: A secondary analysis of an historical cohort study was performed, including 524 patients (59% females). PRIMARY OUTCOME: functional status (Oswestry Disability Index v2.1a). SECONDARY OUTCOMES: catastrophizing (Pain Catastrophizing Scale), FoM (Tampa Scale for Kinesiophobia), and self-efficacy (Pain Self-Efficacy Questionnaire). ASSESSMENTS: pre-, post-treatment, 1, and 12-months follow-up. Paired Student's t-tests were applied and clinical relevancy of improvements was described using minimal clinical important changes. Adjusted multivariate linear regression analyses were performed to explore the unique contribution of self-efficacy. RESULTS: The mean age of patients was 46 (SD = 9.5) years and they had longstanding CLBP (mean 12.5 [SD = 10.8] years). Mean functional status, self-efficacy, and dysfunctional behavioral cognitions improved significantly at post-treatment, with improvements maintained at 12 months follow-up. Post-treatment relevant improvements in self-efficacy and dysfunctional behavioral cognitions ranged from 62.4% (FoM) to 68.7% (self-efficacy). Post-treatment self-efficacy improved the model explaining post-treatment functional disability (basic model R(2) = 0.49, F((6,517)) = 83.67, p < 0.001; final model R(2) = 0.57, F((8,515)) = 85.20, p < 0.001). This was further substantiated by the relative contribution (standardized betas) of self-efficacy: 5.67 times more than catastrophizing and 9.75 times more than FoM. CONCLUSIONS: Targeting self-efficacy contributes to fast improvement in functional status for selected and motivated patients with persistent CLBP. In pain management programs and (online) self-management programs for CLBP, targeting patients' self-efficacy should have a prominent place.