Editing Randomized controlled trial (section)

=== Conflict of interest dangers ===

A 2011 study done to disclose possible [[conflicts of interest]]s in underlying research studies used for medical meta-analyses reviewed 29 meta-analyses and found that conflicts of interests in the studies underlying the meta-analyses were rarely disclosed.  The 29 meta-analyses included 11 from general medicine journals; 15 from specialty medicine journals, and 3 from the [[Cochrane Collaboration|Cochrane]] Database of Systematic Reviews. The 29 meta-analyses reviewed an aggregate of 509 randomized controlled trials (RCTs). Of these, 318 RCTs reported funding sources with 219 (69%) industry funded. 132 of the 509 RCTs reported author conflict of interest disclosures, with 91 studies (69%) disclosing industry financial ties with one or more authors. The information was, however, seldom reflected in the meta-analyses. Only two (7%) reported RCT funding sources and none reported RCT author-industry ties. The authors concluded "without acknowledgment of COI due to industry funding or author industry financial ties from RCTs included in meta-analyses, readers' understanding and appraisal of the evidence from the meta-analysis may be compromised."<ref>{{Cite web |title=How Well Do Meta-Analyses Disclose Conflicts of Interests in Underlying Research Studies &#124; The Cochrane Collaboration |url=http://www.cochrane.org/news/blog/how-well-do-meta-analyses-disclose-conflicts-interests-underlying-research-studies |archive-url=https://web.archive.org/web/20141216145035/http://www.cochrane.org/news/blog/how-well-do-meta-analyses-disclose-conflicts-interests-underlying-research-studies |archive-date=2014-12-16 |access-date=2011-08-19 |publisher=Cochrane.org}}</ref>

Some RCTs are fully or partly funded by the health care industry (e.g., the [[pharmaceutical industry]]) as opposed to government, nonprofit, or other sources. A systematic review published in 2003 found four 1986–2002 articles comparing industry-sponsored and nonindustry-sponsored RCTs, and in all the articles there was a correlation of industry sponsorship and positive study outcome.<ref name="Bekelman-2003">{{Cite journal |vauthors=Bekelman JE, Li Y, Gross CP |year=2003 |title=Scope and impact of financial conflicts of interest in biomedical research: a systematic review |journal=JAMA |volume=289 |issue=4 |pages=454–465 |doi=10.1001/jama.289.4.454 |pmid=12533125}}</ref> A 2004 study of 1999–2001 RCTs published in leading medical and surgical journals determined that industry-funded RCTs "are more likely to be associated with statistically significant pro-industry findings."<ref name="Bhandari-2004">{{Cite journal |vauthors=Bhandari M, Busse JW, Jackowski D, Montori VM, Schünemann H, Sprague S, Mears D, Schemitsch EH, Heels-Ansdell D, Devereaux PJ |date=February 2004 |title=Association between industry funding and statistically significant pro-industry findings in medical and surgical randomized trials |url=http://ecmaj.com/cgi/content/full/170/4/477 |journal=CMAJ |volume=170 |issue=4 |pages=477–480 |pmc=332713 |pmid=14970094}}</ref> These results have been mirrored in trials in surgery, where although industry funding did not affect the rate of trial discontinuation it was however associated with a lower odds of publication for completed trials.<ref name="Chapman-2014">{{Cite journal |vauthors=Chapman SJ, Shelton B, Mahmood H, Fitzgerald JE, Harrison EM, Bhangu A |date=December 2014 |title=Discontinuation and non-publication of surgical randomised controlled trials: observational study |journal=BMJ |volume=349 |pages=g6870 |doi=10.1136/bmj.g6870 |pmc=4260649 |pmid=25491195}}</ref> One possible reason for the pro-industry results in industry-funded published RCTs is [[publication bias]].<ref name="Bhandari-2004" />  Other authors have cited the differing goals of academic and industry sponsored research as contributing to the difference. Commercial sponsors may be more focused on performing trials of drugs that have already shown promise in early stage trials, and on replicating previous positive results to fulfill regulatory requirements for drug approval.<ref>{{Cite journal |vauthors=Ridker PM, Torres J |date=May 2006 |title=Reported outcomes in major cardiovascular clinical trials funded by for-profit and not-for-profit organizations: 2000-2005 |journal=JAMA |volume=295 |issue=19 |pages=2270–2274 |doi=10.1001/jama.295.19.2270 |pmid=16705108 |doi-access=free}}</ref>