The impact of pharmaceutical company funding on results of randomized trials of nicotine replacement therapy for smoking cessation: a meta‐analysis*

Abstract

Compared with independent trials, industry-supported trials were more likely to produce statistically significant results and larger odds ratios. These differences persisted after adjustment for basic trial characteristics. Although we had no data on the amount of funding for each trial, it is possible that more resources led to higher treatment compliance and therefore greater efficacy in industry-supported trials. Differences can also possibly be explained by publication bias with several small, null-effect industry studies not having reached publication. After adjustment for this possible bias, results for industry trials were lower and similar to non-industry results. Similarly, the overall estimate of the net effect for these products reduces to about 5% attributable 1-year successes. This remains of considerable public health benefit. Registration of clinical trials has become mandatory in many countries since most of the trials considered here were conducted, and this should reduce the potential for publication bias in future.

A manifesto for reproducible science

“…The need for these committees grew out of the well-understood financial conflicts of interest that exist in many clinical trials. The sponsor of a trial may be the company manufacturing the product, and any intentional or unintentional influence can distort the study design, analysis and interpretation of results for the ultimate financial benefit of the manufacturer at the cost of the accuracy of the science and the health benefit to the consumers 37,38 . Non-financial conflicts of interest also exist, such as the beliefs and preconceptions of individual scientists and the stakes that researchers have in obtaining publishable results in order to progress their career 39,40 .…”

Dissemination and publication of research findings: an updated review of related biases

“…[288][289][290][291][292][293][294][295][296][297][298] Jorgensen et al compared Cochrane reviews with industry-supported meta-analyses of the same drugs. They found that industry-supported metaanalyses of drugs 'were less transparent, had few reservations about methodological limitations of the included trials, and had more favourable conclusions than the corresponding Cochrane reviews'.…”

RESPONSE TO GREENE ET AL.: INDUSTRY FUNDING AND PLACEBO QUIT RATE IN CLINICAL TRIALS OF NICOTINE REPLACEMENT THERAPY: A COMMENTARY ON ETTER ET AL. (2007)

“…The study by Greene et al [1] is a useful complement to our 2007 study, in which we observed a larger effect for NRT in industry-sponsored trials than in independent trials [2]. We offered two explanations for this result.…”