Discrepancies in findings from effectiveness reviews: the case of health promotion interventions to change cholesterol levels

Abstract

The research reported in this paper aimed to determine how different search strate gies for identifying primary studies, and different inclusion criteria linked to study design, may alter the recommendations of reviews about health promotion inter ventions to change cholesterol levels. Varying search strategies have an effect on the overall number of studies that can be included and on the relative numbers of different study designs. Differences in inclusion criteria result in reviews similar in focus being different in their recommendations. Thus, methodological differences between effectiveness reviews are of substantive concern; the way a review is done affects its 'findings'. (This paper is the second in a series of three. The first was published in the previous issue of the HEJ.)