Selection of potential treatment effect modifiers for the effectiveness of chiropractic manipulation
headache
Since the RCT, this study is based on, is the first to study the effect of chiropractic manipulation for headache in children, we cannot base the choice of potential effect modifiers on results from previous RCTs. Neither are we aware of any attempt to identify potential effect modifiers based on observational data. Therefore, as recommended by Hancock et al. [In some cases, baseline variables were combined to describe constructs which can be aligned with the variables described in the literature. This process is described in Additional file Description of the 16 candidate variables