To identify issues and potential solutions in formulating review questions for complex interventions.
Question formulation is a vital process, and when formulated carefully the question should dictate the most appropriate methods, processes and types of evidence to address it. Producing a well-formulated review question represents a decision making process that aims to define the scope, participants and interventions in a way that enables comparison. In the case of complex interventions, however, the different elements in the intervention can increase heterogeneity in ways that are difficult to predict at the question formulation stage. Further heterogeneity can occur due to unreported variations in implementation and contextual factors. Given these challenges, what are useful approaches to formulating review questions for complex interventions? This workshop will present a brief overview of the challenges of question formulation, followed by specific examples relating to the factors that influence question development for complex intervention reviews. Potential influencing factors include the background knowledge of the review team; review and service users’ perspectives; existing programme theory; heterogeneity in populations; and the organisation of different propositional strands. Possible solutions and the implications of various decisions will be considered via group discussion.