Sub-group analyses
LBP
SECONDARY
We intend to perform exploratory sub-group analyses to assess the effect of a small number of participant baseline variables as treatment effect modifiers. Example variables considered for moderation analyses include the number of previous LBP episodes, baseline levels of physical activity, sedentary behaviour, and age. We intend to later publish a publicly available protocol (i.e. on open science framework) for subgroup analyses which will include hypotheses on the direction of effect. We anticipate only using the primary outcome for these analyses, but this may change if for example we find no main effect for the primary outcome but a worthwhile effect for one of our key secondary outcomes (e.g. disability). We also intend to conduct a Complier Average Causal Effect (CACE) analysis to estimate the effect of the intervention in compliers [