Systematic Reviews are, at their simplest level, comprehensive evidence reviews on a specific topic (e.g., programs, interventions, research questions). Exhaustive literature searches are completed and located evidence (i.e., journal articles) is analysed, synthesized, compared, assessed for quality, and summarized. Systematic reviews began in the clinical sciences and typically use randomized controlled trials (RCT) as the 'gold standard' in terms of evidence.
Since the use of RCTs can often be unethical in population or public health studies, systematic reviews are less common in the population or public health literature. However, in recent years more studies that use qualitative methodology have begun to be included in systematic reviews. An important background article on systematic reviews is:
Mullen PD, Ramirez G. The promise and pitfalls of systematic reviews. Annual Review of Public Health. 27:81-102, 2006. [PubMed]
The systematic review "movement" that has transformed medical journal reports of clinical trials and reviews of clinical trials has taken hold in public health, with the most recent milestone, the publication of the first edition of The Guide to Community Health Services in 2005. In this paper we define and distinguish current terms, point out important resources for systematic reviews, describe the impact of systematic review on the quality of primary studies and summaries of the evidence, and provide perspectives on the promise of systematic reviews for shaping the agenda for public health research. Several pitfalls are discussed, including a false sense of rigor implied by the terms "systematic review" and "meta-analysis" and substantial variation in the validity of claims that a particular intervention is "evidence based," and the difficulty of translating conclusions from systematic reviews into public health advocacy and practice.
Cochrane Database of Systematic Reviews: Cohrane Systematic Reviews are the 'Gold Standard' of systematic reviews; over 6000 systematic reviews and protocols (reviews currently underway) are available.
PubMed Clinical Queries: Systematic reviews, meta-analyses, and other reviews are available from PubMed via Clinical Queries
The Community Guide: Initiative that uses systematic reviews to answer questions about what policies, interventions, programs, etc work in public health. Can search by Topic Area, Policies, Education, Funding and more.
Health-Evidence.ca: A compilation of Canadian health promotion and public health interventions; each study is assessed and ranked in terms of study strength.
PROSPERO: A new international registry of systematic review protocols developed in the UK. Prospero advocates for registration of reviews to limit reporting bias. As it is a new resource, the number of reviews available is limited at this point.
Systematic Reviews Journal: A new open-access journal that encompasses all aspects of the design, conduct, and reporting of systematic reviews
Resources for Systematic Reviews & Evidence-based Public Health Practice - From the University of Texas School of Public Health Library, this site contains a wealth of information on: