Real world reviews: a beginner's guide to undertaking systematic reviews of public health policy interventions

Abstract

Background The systematic review is becoming an increasingly popular and established research method in public health. Obtaining systematic review skills are therefore becoming a common requirement for most public health researchers and practitioners. However, most researchers still remain apprehensive about conducting their first systematic review. This is often because an 'ideal' type of systematic review is promoted in the methods literature. Methods This brief guide is intended to help dispel these concerns by providing an accessible overview of a 'real' approach to conducting systematic reviews. The guide draws upon an extensive practical experience of conducting various types of systematic reviews of complex social interventions. Results The paper discusses what a systematic review is and how definitions vary. It describes the stages of a review in simple terms. It then draws on case study reviews to reflect on five key practical aspects of the conduct of the method, outlining debates and potential ways to make the method shorter and smarterdenhancing the speed of production of systematic reviews and reducing labour intensity while still maintaining high methodological standards. Conclusion There are clear advantages in conducting the high quality pragmatic reviews that this guide has described: (1) time and labour resources are saved; (2) it enables reviewers to inform or respond to developments in policy and practice in a timelier manner; and (3) it encourages researchers to conduct systematic reviews before embarking on primary research. Well-conducted systematic reviews remain a valuable part of the public health methodological tool box.

Systematic reviews of the evidence on the nature, extent and effects of food marketing to children. A retrospective summary

“…The methods are intended to be transparent and therefore replicable, and to minimise selection bias. Systematic review is increasingly used to inform the development of policy and identify gaps in the research literature (Bambra, 2011;Dobbins, Jack, Thomas et al, 2007).…”

Risk/Benefit Communication about Food—A Systematic Review of the Literature

“…A systematic review uses an explicit, rigorous, and transparent methodology for identifying, selecting, and coding papers (Greenhalgh et al, 2005). It aims to support evidence based policy and practice (Chalmers, 2003) through the identification of the best available evidence for a particular research question (Bambra, 2011). To ensure rigor and transparency, a systematic review should follow an established process for: (1) identifying the review question; (2) locating and selecting relevant studies; (3) critically appraising the selected studies; (4) analyzing and synthesizing the findings from the studies; and (5) reporting (and disseminating) the review findings (Briner and Rousseau, 2011).…”

Critique of the review of 'Water fluoridation for the prevention of dental caries' published by the Cochrane Collaboration in 2015

“…It is a population level intervention and should be judged as such. [6][7][8][9][10][11][12][13][14][15] Therefore, measurement of the impact of water fluoridation is not like a clinical intervention for the following reasons. First, the context in which water is fluoridated is complex: 16,17 its introduction and maintenance requires legislation, installation and maintenance of equipment, technical training of water treatment plant operators, development and adherence to procedures and processes, and continuity of supply and regular monitoring.…”

“…Although RCTs are the method of choice for evaluating the effectiveness of medicines and some clinical interventions, literature published during the past 20 years has indicated that they are inappropriate for evaluating public health preventive programmes and other complex interventions. [6][7][8][9][10][11][12][13][14][15] Using water fluoridation as an example, it is not possible to randomly assign individuals to fluoridated and non-fluoridated water supplies. RCTs may have high internal validity, but they also may have poor external validity.…”