Guest blog: Over 80% of venous ulcer trials have not been registered
In our recent systematic review of 204 clinical trials involving venous leg ulcers published in 76 journals since 2001, we found that over 80% of trials had not been registered.
This included trials of drugs, medical devices, and other interventions.
Only 38 of the trials in our review reported registration, while 166 trials were not registered. Registration rates have been increasing in recent years, but fewer than half of the trials we looked at were registered in any given year.
The registered trials in our sample were twice as likely to report sufficient information on randomisation and allocation concealment, and were about three times more likely to report adverse events.
In theory, the International Committee of Medical Journal Editors (ICMJE) has required prospective registration of trials before publication since 2004. However, according to the ICMJE website, 59 of the 76 journals that published venous ulcer trials have not committed to supporting trial registration. This includes seven of the 10 journals that published five or more trials.
(As others have pointed out, journal endorsement or encouragement alone will be insufficient to ensure comprehensive trial registration. Journal editors and reviewers need to be much more viligant in their scrutiny of trials submitted for publication. Note that registering clinical trials has been a global ethics requirement since 2013.)
Our review also found that venous ulcer trials reported harms in a wide variety of ways:
78 trials did not include any adverse events in the report
41 trials reported all-cause adverse events
18 trials reported only venous ulcer related adverse events
23 trials reported only treatment-related events
2 trials reported only serious adverse events
18 trials reported no adverse events occurred (without reporting what type of event might have been included)
24 trials did not specify what adverse events were being reported
Underlying this dynamic is lack of consistent guidance from key players:
The US Food and Drug Administration (FDA) does not include any relevant guidance in their document on trials of treatments for chronic cutaneous ulcers.
The 2010 CONSORT update and checklist only requires reporting of important harms, although it does reference the 2004 extension on reporting of harms.
Efforts to reach a consensus on reporting core outcomes in venous ulcer trials have yet to bear fruit.
Trial registration is the single modifiable factor that journal editors could use to improve reporting in venous ulcer trials.
This guest blog was written by Andrew Jull. He is a Professor of Nursing at the University of Auckland, an editor with the Cochrane Collaboration Wound Review Group, and leads the 4VLU Research Collaboration in New Zealand. TranspariMED did not fact check the contents of this blog. Professor Jull can be contacted via Twitter: @1commonreader