Chapter 3: Defining the criteria for including studies and how they will be grouped for the synthesis | Cochrane
Cite this chapter as: McKenzie JE, Brennan SE, Ryan RE, Thomson HJ, Johnston RV, Thomas J. Chapter 3: Defining the criteria for including studies and how they will be grouped for the synthesis [last updated August 2023]. In: Higgins JP, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, et al, editor(s). Cochrane Handbook for Systematic Reviews of Interventions version 6.5. Cochrane, 2024. Available from cochrane.org/handbook. One of the features that distinguishes a systematic review from a narrative review is that systematic review authors should pre-specify criteria for including and excluding studies in the review (eligibility criteria, see MECIR Box 3.2.a). When developing the protocol, one of the first steps is to determine the elements of the review question (including the population, intervention(s), comparator(s) and outcomes, or PICO elements) and how the intervention, in the specified population, produces the expected outcomes (see Chapter 2, Section 2.5.1 and Chapter 17, Sect