Patient characteristics and stratification factors reported within rheumatology: A scoping review of randomized trials included in Cochrane reviews

Background: Contextual factors (CFs) are important for interpreting the results of trials. The so-called ‘effect modifying contextual factors’ (EM-CFs) are factors modifying the treatment effect in a trial. To ensure consistent reporting and stratification of trial results, allowing for future evidence synthesis, a consensus-based set of important EM-CFs is needed. A first step involves collecting candidate EM-CFs.