Introduction
What is new?
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Information addressing the challenges of systematic reviews of complex multicomponent interventions (CMCIs) is presented in one document.
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This information is a synthesis of the current literature and the practices of leading international experts.
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We provide a framework to consider when systematically reviewing CMCIs and analyzing the results.
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We provide an initial list of elements that should be reported in research reports and systematic reviews of complex multicomponent health care interventions.
The Agency for Healthcare Research and Quality (AHRQ)'s Effective Health Care program receives requests to synthesize evidence regarding the effectiveness and harms of complex multicomponent health care interventions, such as quality improvement, infection control, and health care informatics interventions. Systematic reviews of complex multicomponent interventions (CMCIs) provide clinicians, policymakers, and others with information about the benefits and harms of interventions for decision making about implementation; however, because of their complexity, conducting reviews on multicomponent interventions is challenging.
A number of features distinguish CMCIs from other interventions such as devices or pharmaceuticals. First, CMCIs are commonly implemented at the level of an inpatient unit, outpatient clinic, hospital, or health system rather than individual patients. Because setting characteristics may interact with the intervention, it is critical to understand and enumerate those aspects that may modify the intervention's effects and synthesize the available interventions in context of those factors. Second, it may be uncommon for studies to examine identical combinations of components. This is particularly true as CMCIs evolve over time, and researchers add or remove components based on ongoing experience. Third, the “complexity” of CMCIs implies that the interventions cannot be reduced to the sum of their individual components but rather should be analyzed as “systems.” This challenges reviewers to delineate essential from nonessential components. Ultimately, the generalizability and usability of findings from syntheses of CMCI studies may be limited unless the reviewer can address these challenges [1].
Our purpose was to outline approaches to the challenges of conducting systematic reviews of CMCIs as a step toward the development of guidance.