When should systematic reviews of effects restrict studies to those conducted in low- and middle-income countries: A proposal?

Article type
Authors
Munabi-Babigumira S1, Lewin S1, Glenton C1, Oxman A1
1Norwegian Knowledge Centre for the Health Service, Norway
Abstract
Background: The Norwegian satellite of the Cochrane Effective Practice and Organisation of Care (EPOC) group produces reviews that address health system questions relevant to low- and middle- income countries (LMICs). It is not always clear if review authors should restrict searches to LMICs or focus on the global evidence.

Objectives: To suggest issues to consider when deciding whether or not to restrict systematic reviews to LMICs.

Methods: Reasons to restrict the focus of a review to LMICs were developed through discussions among the EPOC editorial team.

Results: Suggested reasons to restrict a review to LMIC are: i)The intervention(s) and/or problem that the review addresses is highly relevant in LMIC and of little or no relevance in high-income countries (HICs), and; ii)There are compelling reasons to believe that the problem or the intervention(s) or the outcomes of interest are different in LMICs and HICs, and the intervention(s) would be expected to function differently in LMICs and HICs, so that the evidence would be unlikely to be transferable between LMICs and HICs. Reasons that do not adequately justify restricting the focus of an EPOC review to studies from LMICs include: i)The interventions are common in LMICs and uncommon in HICs, but there are not compelling reasons to believe that the problem or the interventions or the outcomes of interest are different in LMICs and HICs, and the intervention(s) would not be expected to function differently in LMICs and HICs; and ii)The researchers or those who commissioned the review are particularly interested in evidence from LMICs.

Conclusions: When proposing a review that is restricted to evidence from LMIC, authors need to justify why. Further work is needed to examine whether there are differences in effects for similar interventions implemented in LMICs and HICs.