Effects of self-discrepancies on activity-related behaviour: explaining disability and quality of life in patients with chronic low back pain.

In chronic low back pain (CLBP) research, the self-discrepancy model has been applied to explain dysfunctional avoidance and persistence behaviour. The main aim of this study was to evaluate whether specific self-discrepancies in patients with CLBP are associated with the abovementioned types of activity-related behaviour and whether changes in self-discrepancies over time are associated with changes in activity-related behaviour. Furthermore, the aim was to evaluate whether avoidance and persistence behaviour are associated with a higher level of disability and a diminished quality of life and whether changes over time in avoidance and persistence behaviour result in changes in disability and quality of life. A longitudinal cohort study in a sample of patients with CLBP (N=116), in which self-discrepancies, disability, quality of life, and objectively registered characteristics of activity-related behaviour were measured, was performed to evaluate the pathways in the aforementioned self-discrepancy model. Results indicate that patients with CLBP who feel closer to their ideal-other show more characteristics of persistence behaviour. Patients who move further away from their ideal-own also show more characteristics of persistence behaviour. Furthermore, in patients characterized as avoider, a decrease in a patient's daily uptime was associated with a decrease of mental health-related quality of life.