“Nonindustry-Sponsored Preclinical Studies on Statins Yield Greater Efficacy Estimates Than Industry-Sponsored Studies: A Meta-Analysis”, 2013-12-09 (; backlinks; similar):
Industry-sponsored clinical drug studies are associated with publication of outcomes that favor the sponsor, even when controlling for potential bias in the methods used. However, the influence of sponsorship bias has not been examined in preclinical animal studies.
We performed a meta-analysis of preclinical statin studies to determine whether industry sponsorship is associated with either increased effect sizes of efficacy outcomes and/or risks of bias in a cohort of published preclinical statin studies. We searched MEDLINE (January 1966–April 2012) and identified 63 studies evaluating the effects of statins on atherosclerosis outcomes in animals. Two coders independently extracted study design criteria aimed at reducing bias, results for all relevant outcomes, sponsorship source, and investigator financial ties. The I2 statistic was used to examine heterogeneity. We calculated the standardized mean difference (SMD) for each outcome and pooled data across studies to estimate the pooled average SMD using random effects models. In a priori subgroup analyses, we assessed statin efficacy by outcome measured, sponsorship source, presence or absence of financial conflict information, use of an optimal time window for outcome assessment, accounting for all animals, inclusion criteria, blinding, and randomization.
The effect of statins was statistically-significantly larger for studies sponsored by nonindustry sources (−1.99; 95% CI −2.68, −1.31) versus studies sponsored by industry (−0.73; 95% CI −1.00, −0.47) (p < 0.001). Statin efficacy did not differ by disclosure of financial conflict information, use of an optimal time window for outcome assessment, accounting for all animals, inclusion criteria, blinding, and randomization. Possible reasons for the differences between nonindustry-sponsored and industry-sponsored studies, such as selective reporting of outcomes, require further study.
Author Summary: Industry-sponsored clinical drug studies are associated with publication of outcomes that favor the sponsor, even when controlling for potential bias in the methods used. However, the influence of sponsorship bias has not been examined in preclinical animal studies. We performed a meta-analysis to identify whether industry sponsorship is associated with increased risks of bias or effect sizes of outcomes in a cohort of published preclinical studies of the effects of statins on outcomes related to atherosclerosis. We found that in contrast to clinical studies, the effect of statins was statistically-significantly larger for studies sponsored by nonindustry sources versus studies sponsored by industry. Furthermore, statin efficacy did not differ with respect to disclosure of financial conflict information, use of an optimal time window for outcome assessment, accounting for all animals, inclusion criteria, blinding, and randomization. Possible reasons for the differences between nonindustry-sponsored and industry-sponsored studies, such as selective outcome reporting, require further study. Overall, our findings provide empirical evidence regarding the impact of funding and other methodological criteria on research outcomes.