Methodology Review

Industry sponsorship and research outcome

  1. Andreas Lundh1,*,
  2. Sergio Sismondo2,
  3. Joel Lexchin3,
  4. Octavian A Busuioc2,
  5. Lisa Bero4

Editorial Group: Cochrane Methodology Review Group

Published Online: 12 DEC 2012

Assessed as up-to-date: 30 SEP 2010

DOI: 10.1002/14651858.MR000033.pub2

How to Cite

Lundh A, Sismondo S, Lexchin J, Busuioc OA, Bero L. Industry sponsorship and research outcome. Cochrane Database of Systematic Reviews 2012, Issue 12. Art. No.: MR000033. DOI: 10.1002/14651858.MR000033.pub2.

Author Information

  1. 1

    Rigshospitalet, The Nordic Cochrane Centre, Copenhagen, Denmark

  2. 2

    Queen's University, Department of Philosophy, Kingston, Ontario, Canada

  3. 3

    York University, School of Health Policy and Management, Toronto, Ontario, Canada

  4. 4

    University of California San Francisco, Department of Clinical Pharmacy and Institute for Health Policy Studies, San Francisco, California, USA

*Andreas Lundh, The Nordic Cochrane Centre, Rigshospitalet, Blegdamsvej 9, 7811, Copenhagen, DK-2100, Denmark. al@cochrane.dk.

Publication History

  1. Publication Status: Edited (no change to conclusions), comment added to review
  2. Published Online: 12 DEC 2012

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Abstract

  1. Top of page
  2. Abstract
  3. Plain language summary

Background

Clinical research affecting how doctors practice medicine is increasingly sponsored by companies that make drugs and medical devices. Previous systematic reviews have found that pharmaceutical industry sponsored studies are more often favorable to the sponsor’s product compared with studies with other sources of sponsorship. This review is an update using more stringent methodology and also investigating sponsorship of device studies.

Objectives

To investigate whether industry sponsored drug and device studies have more favorable outcomes and differ in risk of bias, compared with studies having other sources of sponsorship.

Search methods

We searched MEDLINE (1948 to September 2010), EMBASE (1980 to September 2010), the Cochrane Methodology Register (Issue 4, 2010) and Web of Science (August 2011). In addition, we searched reference lists of included papers, previous systematic reviews and author files.

Selection criteria

Cross-sectional studies, cohort studies, systematic reviews and meta-analyses that quantitatively compared primary research studies of drugs or medical devices sponsored by industry with studies with other sources of sponsorship. We had no language restrictions.

Data collection and analysis

Two assessors identified potentially relevant papers, and a decision about final inclusion was made by all authors. Two assessors extracted data, and we contacted authors of included papers for additional unpublished data. Outcomes included favorable results, favorable conclusions, effect size, risk of bias and whether the conclusions agreed with the study results. Two assessors assessed risk of bias of included papers. We calculated pooled risk ratios (RR) for dichotomous data (with 95% confidence intervals).

Main results

Forty-eight papers were included. Industry sponsored studies more often had favorable efficacy results, risk ratio (RR): 1.32 (95% confidence interval (CI): 1.21 to 1.44), harms results RR: 1.87 (95% CI: 1.54 to 2.27) and conclusions RR: 1.31 (95% CI: 1.20 to 1.44) compared with non-industry sponsored studies. Ten papers reported on sponsorship and effect size, but could not be pooled due to differences in their reporting of data. The results were heterogeneous; five papers found larger effect sizes in industry sponsored studies compared with non-industry sponsored studies and five papers did not find a difference in effect size. Only two papers (including 120 device studies) reported separate data for devices and we did not find a difference between drug and device studies on the association between sponsorship and conclusions (test for interaction, P = 0.23). Comparing industry and non-industry sponsored studies, we did not find a difference in risk of bias from sequence generation, allocation concealment and follow-up. However, industry sponsored studies more often had low risk of bias from blinding, RR: 1.32 (95% CI: 1.05 to 1.65), compared with non-industry sponsored studies. In industry sponsored studies, there was less agreement between the results and the conclusions than in non-industry sponsored studies, RR: 0.84 (95% CI: 0.70 to 1.01).

Authors' conclusions

Sponsorship of drug and device studies by the manufacturing company leads to more favorable results and conclusions than sponsorship by other sources. Our analyses suggest the existence of an industry bias that cannot be explained by standard 'Risk of bias' assessments.

 

Plain language summary

  1. Top of page
  2. Abstract
  3. Plain language summary

Industry sponsorship and research outcome

Results from clinical studies on drugs and medical devices affect how doctors practice medicine and thereby the treatments offered to patients. However, clinical research is increasingly sponsored by companies that make these products, either because the companies directly perform the studies, or fully or partially fund them. Previous research has found that pharmaceutical industry sponsored studies tend to favor the sponsors’ drugs much more than studies with any other sources of sponsorship. This suggests that industry sponsored studies are biased in favor of the sponsor’s products.

This review is an update of a previous review on this topic that looked only at drug studies. It uses more rigorous methodology and also investigates sponsorship of medical device studies. The primary aim of the review was to find out whether the published results and overall conclusions of industry sponsored drug and device studies were more likely to favor the sponsors’ products, compared with studies with other sources of sponsorship. The secondary aim was to find out whether such industry sponsored studies used methods that increase the risk of bias, again compared with studies with other sources of sponsorship. We did a comprehensive search of all relevant papers published before September 2010 and included 48 papers in our review.

Industry sponsored drug and device studies more often had favorable efficacy results, (risk ratio (RR): 1.32, 95% confidence interval (CI): 1.21 to 1.44), harms results (RR: 1.87, 95% CI: 1.54 to 2.27) and overall conclusions (RR: 1.31, 95% CI: 1.20 to 1.44), compared with non-industry sponsored drug and device studies. We did not find a difference between industry and non-industry sponsored studies with respect to standard factors that may increase the risk of bias, except for blinding: industry sponsored studies reported satisfactory blinding more often than non-industry sponsored studies. We did not find a difference between drug and device studies on the association between sponsorship and conclusions. In industry sponsored studies, there was less agreement between the results and the conclusions than in non-industry sponsored studies, RR: 0.84 (95% CI: 0.70 to 1.01). Our analysis suggests that industry sponsored drug and device studies are more often favorable to the sponsor’s products than non-industry sponsored drug and device studies due to biases that cannot be explained by standard 'Risk of bias' assessment tools.