Article type
Year
Abstract
Background: A systematic review may evaluate different aspects of a healthcare intervention. To accommodate the evaluation of various research questions, the inclusion of more than one study design may be necessary.
Objectives: To find and describe articles on methodological issues concerning the incorporation of multiple types of study designs in systematic reviews on healthcare interventions.
Methods: We searched PubMed, the Cochrane Database of Systematic Reviews, and the Cochrane Methodology Register on 31 March 2012 and identified 42 articles that reported on the integration of single or multiple study designs in systematic reviews. We summarized the contents of the articles qualitatively and assessed theoretical and empirical evidence.
Results: Many examples of reviews incorporating multiple types of studies exist and every study design can serve a specific purpose. 85% (36 of 42) of reviews reported that nonrandomized studies should be integrated in systematic reviews to complement available RCTs or replace lacking RCTs. The clinical questions of a systematic review determine the types of designs that are necessary or sufficient to provide the best possible answers.
Conclusions: The integration of multiple study designs in systematic reviews is required if patients are to be informed about the many facets of patient-relevant issues of healthcare interventions.
Objectives: To find and describe articles on methodological issues concerning the incorporation of multiple types of study designs in systematic reviews on healthcare interventions.
Methods: We searched PubMed, the Cochrane Database of Systematic Reviews, and the Cochrane Methodology Register on 31 March 2012 and identified 42 articles that reported on the integration of single or multiple study designs in systematic reviews. We summarized the contents of the articles qualitatively and assessed theoretical and empirical evidence.
Results: Many examples of reviews incorporating multiple types of studies exist and every study design can serve a specific purpose. 85% (36 of 42) of reviews reported that nonrandomized studies should be integrated in systematic reviews to complement available RCTs or replace lacking RCTs. The clinical questions of a systematic review determine the types of designs that are necessary or sufficient to provide the best possible answers.
Conclusions: The integration of multiple study designs in systematic reviews is required if patients are to be informed about the many facets of patient-relevant issues of healthcare interventions.