3 research outputs found
Financial conflicts of interest and reporting bias regarding the association between sugar-sweetened beverages and weight gain: a systematic review of systematic reviews
Background: Industry sponsorsâ financial interests might bias the conclusions of scientific research. We examined whether
financial industry funding or the disclosure of potential conflicts of interest influenced the results of published systematic
reviews (SRs) conducted in the field of sugar-sweetened beverages (SSBs) and weight gain or obesity.
Methods and Findings: We conducted a search of the PubMed, Cochrane Library, and Scopus databases to identify
published SRs from the inception of the databases to August 31, 2013, on the association between SSB consumption and
weight gain or obesity. SR conclusions were independently classified by two researchers into two groups: those that found
a positive association and those that did not. These two reviewers were blinded with respect to the stated source of funding
and the disclosure of conflicts of interest. We identified 17 SRs (with 18 conclusions). In six of the SRs a financial conflict of
interest with some food industry was disclosed. Among those reviews without any reported conflict of interest, 83.3% of the
conclusions (10/12) were that SSB consumption could be a potential risk factor for weight gain. In contrast, the same
percentage of conclusions, 83.3% (5/6), of those SRs disclosing some financial conflict of interest with the food industry
were that the scientific evidence was insufficient to support a positive association between SSB consumption and weight
gain or obesity. Those reviews with conflicts of interest were five times more likely to present a conclusion of no positive
association than those without them (relative risk: 5.0, 95% CI: 1.3â19.3). An important limitation of this study is the
impossibility of ruling out the existence of publication bias among those studies not declaring any conflict of interest.
However, the best large randomized trials also support a direct association between SSB consumption and weight gain or
obesity.
Conclusions: Financial conflicts of interest may bias conclusions from SRs on SSB consumption and weight gain or obesity