Systematic reviews on tobacco control from Cochrane and the Community Guide: Differences and similarities

Department of Health Promotion, School of Public Health, Sackler Faculty of Medicine, Tel Aviv University, Ramat Aviv, Israel.
Journal of clinical epidemiology (Impact Factor: 3.42). 06/2010; 63(6):596-606. DOI: 10.1016/j.jclinepi.2009.09.010
Source: PubMed


To compare the methods and findings of systematic reviews (SRs) on common tobacco control interventions from two organizations: the Cochrane Collaboration ("Cochrane") and the US Task Force for Community Preventive Services ("the Guide").
Literature review. We retrieved all reviews pertaining to tobacco control produced by the Cochrane and the Guide. We identified seven common topics and compared methods and findings of the retrieved reviews.
There was considerable variability in the designs of included studies and methods of data synthesis. On average, Cochrane identified more studies than did the Guide (Mean 43.7 vs. 19.0), with only limited overlap between sets of included studies. Most Cochrane reviews (71.4%) were synthesized narratively, whereas most Guide reviews (85.7%) were synthesized using a median of effect size. Despite these differences, findings of the reviews yielded substantial agreement.
Cochrane and the Guide conduct SRs on similar tobacco control-related topics differently. The SRs of the two organizations include overlapping, but nonidentical sets, of studies. Still, they usually reach similar conclusions. Identification of all pertinent original studies seems to be a weak point in the SR process. Policy makers should use reviews from both organizations in formulating tobacco control policy.

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    • "Furthermore, the limited sensitivity of search strategies is shared by many, if not most, reviews: it has been pointed out that the systematic reviews of the same topic by the Cochrane Collaboration and the Task Force on Community Preventive Services differ not only in methods of synthesis of the results, but also in the number of identified studies, with an only limited overlap between sets of included studies [80]. Indeed, our meta-review identified systematic reviews with similar objectives, covering similar periods of time that had retrieved different numbers of primary RCTs. "
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    • "Reviewing all of the evidence is rarely a feasible strategy for those developing plans. Yet, even a review of reviews in this field is challenging, especially as reviews may be of varying quality and produce conflicting results [19]. An alternative is to draw on authoritative sources of systematic reviews, and base recommendations on interventions proposed by leading agencies. "
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