Methods used to select results to include in meta-analyses of nutrition research: A meta-research study

Abstract

Objectives: To investigate how often review authors encounter multiple results from included studies that are eligible for inclusion in a particular meta-analysis, and how often methods to select results are specified. Methods: MEDLINE and Epistemonikos were searched (January 2018–June 2019) to identify systematic reviews with meta-analysis of the association between food/diet and health-related outcomes. A random sample of these reviews was selected, and for the first presented (index) meta-analysis, rules used to select effect estimates to include in this meta-analysis were extracted from the reviews and their protocols. All effect estimates from the primary studies that were eligible for ..