Statistical Analysis Plan (SAP) – DREAM: an adaptive, randomised, placebo-controlled trial of duloxetine for reducing leg pain in people with chronic sciatica

DREAM is a randomised, superiority, parallel-group, placebo-controlled, participant, clinician, and assessor blinded trial with an adaptive group sequential design that allows early stopping for efficacy or futility. The purpose is to investigate whether taking 60 mg of duloxetine daily for 12 weeks in addition to guideline-recommended advice, compared with placebo in addition to guideline-recommended advice, can reduce leg pain intensity in individuals with chronic sciatica.

The primary outcome is leg pain intensity measured on a 0-10 numerical pain rating scale. It will be analysed using a repeated-measures linear mixed model. This statistical analysis plan pre-specifies the methods of analysis to be used in the interim analysis and the final analysis for the outcomes and key variables collected in the trial. It includes planned sensitivity analyses for the final analysis, including covariate adjustments and subgroup analyses, as well as the health economics analysis plan.