Challenges in synthesizing and interpreting the evidence from a systematic review of multifactorial interventions to prevent functional decline in older adults

A systematic review of multifactorial assessment and management interventions to prevent functional decline in older adults was undertaken for the U.S. Preventive Services Task Force. It was not possible to determine net benefit because of heterogeneity of studies, including how older adults were selected and their risk of functional decline; the broad spectrum and multifactorial nature of interventions evaluated; the suboptimal and inconsistent use of outcomes measured; and the inconsistent and inadequate reporting of data that might allow comparison of populations, interventions, and outcomes between studies. This review process illustrated the complexities encountered when synthesizing and interpreting the evidence in geriatric research and methods of reviewing complex interventions and multiple interrelated health outcomes. This article summarizes the review findings, focusing on methodological challenges, and offers suggestions to researchers on the design, reporting, and analysis of trials that would help address these challenges and allow for better interpretation of evidence in the future.