Results from many large clinical trials are never published

A new analysis of 585 large, randomized clinical trials registered with ClinicalTrials.gov finds that 29 percent have not been published in scientific journals. In addition, nearly 78 percent of the unpublished trials had no results available on the website, either.

As a result, nearly 300,000 people who were enrolled in the 171 unpublished trials "were exposed to the risks of trial participation without the societal benefits which accompany the dissemination of trial results," said Christopher W. Jones, MD, a former resident physician at University of North Carolina School of Medicine who is now an attending physician at Cooper Medical School of Rowan University in Camden, N.J. and lead author of the study published in the Oct. 29, 2013 issue of the British Medical Journal.

Non-publication of clinical trials has been a controversial issue in recent years. In particular, industry-funded – such as those paid for by pharmaceutical companies – have come under fire on allegations that such trials are often not published when the results are not favorable to the drug or other product being tested.

Against this background, the study authors set out to determine what happened to 585 large, with at least 500 participants that were registered with ClinicalTrials.gov and completed before January 2009. ClinicalTrials.gov is a website that provides patients, their family members, , researchers and the public with easy access to information on publicly and privately supported clinical studies on a wide range of diseases and conditions.

Of the 585 registered trials, 171 (29 percent) had not been published by November 2012, when the final literature search for this study was conducted. Non-publication was more common among trials that received industry funding (32 percent ) compared to those without industry funding (18 percent). Of the 171 unpublished trials, 133 (78 percent) had no results available in ClinicalTrials.gov.

"Clinical trials are an essential source of information for how to care for patients. Additional policies are needed to ensure that results of all large clinical are made publicly available in a timely manner," said Timothy F. Platts-Mills, MD, an assistant professor of emergency medicine at UNC and senior author of the study.

add to favorites email to friend print save as pdf

Related Stories

Children continue to be underrepresented in drug trials

Jul 23, 2012

(HealthDay) -- Even for conditions with a high pediatric disease burden, only a small proportion of clinical drug trials study pediatric patients, according to research published online July 23 in Pediatrics.

Recommended for you

What are the chances that your dad isn't your dad?

Apr 16, 2014

How confident are you that the man you call dad is really your biological father? If you believe some of the most commonly-quoted figures, you could be forgiven for not being very confident at all. But how ...

New technology that is revealing the science of chewing

Apr 15, 2014

CSIRO's 3D mastication modelling, demonstrated for the first time in Melbourne today, is starting to provide researchers with new understanding of how to reduce salt, sugar and fat in food products, as well ...

After skin cancer, removable model replaces real ear

Apr 11, 2014

(HealthDay)—During his 10-year struggle with basal cell carcinoma, Henry Fiorentini emerged minus his right ear, and minus the hearing that goes with it. The good news: Today, the 56-year-old IT programmer ...

Italy scraps ban on donor-assisted reproduction

Apr 09, 2014

Italy's Constitutional Court on Wednesday struck down a Catholic Church-backed ban against assisted reproduction with sperm or egg donors that has forced thousands of sterile couples to seek help abroad.

User comments

Adjust slider to filter visible comments by rank

Display comments: newest first

Sinister1811
3 / 5 (16) Oct 30, 2013
Nooo.. Oh really?! And that, my friends, is why in this stone age there isn't a cure or effective treatment for anything.

I looked at that site a few times, and they don't publish anything. This is just the typical incompetence that you'd expect from high paid medical research these days.
Sinister1811
3 / 5 (16) Oct 30, 2013
Knowing this, it does actually make me wonder what they do with all this research money they get from grants and charity donations.