Primary analysis
LBP
REGRESSION, EVENT, RECURRENCE
Cox regression is planned to assess the effect of the treatment group on Hazard Ratios (HR) and to adjust for prognostic factors for recurrence of LBP, if these are unbalanced between groups despite randomisation. Kaplan–Meier survival plots will be constructed to visually display survival curves, with patients censored on the day of their last successful follow-up, or when the participant was identified to have the event (i.e. recurrence), whichever occurs first. HR and median survival times with 95% CIs will be reported. The effect of including the variables that were used for the stratified randomisation as strata in these analyses will also be assessed (i.e. clinician versus community referral and the number of previous episodes (up to 2 versus > 2 episodes)).