The authors of the study -- published in the current issue of the Journal of the American Medical Association -- recommend that researchers resist pressures to end clinical trials early and continue trials for longer periods before even considering premature termination.
“Our research shows that in most cases early stopping of clinical trials resulted in misleading estimates of treatment effects. These misleading estimates are likely to result in misguided decisions about the trade-off between risks and benefits of a therapy,” says Victor Montori, M.D., Mayo Clinic endocrinologist and corresponding author of the study. “On average, treatments with no effect would show a reduction in relative risk of almost 30 percent in stopped early trials. Treatments with a true relative risk reduction of 20 percent would show a reduction of over 40 percent.”
The clinical trials that Dr. Montori and colleagues studied were ended early because of a convincing -- and usually large -- apparent difference between an experimental treatment and an existing standard therapy. The studies were ended so participants taking a placebo or less effective medications could also take the studied drug. It usually also allows physicians to prescribe the therapy sooner because it will reach the market earlier.
Dr. Montori says almost everyone involved benefits from a trial ending early -- doctors, researchers, funding sources, pharmaceutical firms, scientific journals, even reporters -- everyone except the patient, who may end up receiving a therapy on the basis of misleading information about its benefits.
The researchers examined 63 medical questions regarding 91 truncated trials and compared them to 424 comparable trials that were not stopped early. Results showed that the studies that were stopped -- especially smaller trials of a few hundred participants -- had exaggerated or misleading treatment effects. Those misleading findings are often compounded downstream because researchers are less likely to return to the topic after what is perceived as a significant successful finding.
The authors recommend that researchers use restraint and truncate clinical trials only near the end of a study and then only with “a very good reason.” Otherwise, says Dr. Montori, patients and physicians will be making treatment choices based on inaccurate information, or worse, opting for one treatment when another may be more appropriate.
The study was supported by the Medical Research Council of the U.K. Other authors include Dirk Bassler, M.D.; Matthias Briel, M.D.; Qi Zhou, Ph.D.; Stephen Walter, Ph.D.; Gordon Guyatt, M.D.; and Diane Heels-Ansdell, all of McMaster University, Ontario; Melanie Lane, Mayo Clinic; and Paul Glasziou, M.B.B.S., Ph.D., University of Oxford, England.About Mayo Clinic
Robert Nellis | Newswise Science News
Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
Computer scientists use wave packet theory to develop realistic, detailed water wave simulations in real time. Their results will be presented at this year’s SIGGRAPH conference.
Think about the last time you were at a lake, river, or the ocean. Remember the ripples of the water, the waves crashing against the rocks, the wake following...
An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.
Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...
Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.
Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...
Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.
As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...
Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.
With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...
19.06.2017 | Event News
13.06.2017 | Event News
13.06.2017 | Event News
29.06.2017 | Physics and Astronomy
29.06.2017 | Life Sciences
29.06.2017 | Health and Medicine