“Millions of Animals May Be Missing from Scientific Studies”, 2020-10-14 ():
Most animals used in biomedical experiments are not accounted for in published papers, a first-of-its-kind study suggests. The analysis found that only one-quarter of more than 5500 lab animals used over a 2-year period at one university in the Netherlands ended up being mentioned in a scientific paper afterward. The researchers believe the pattern could be similar at institutions around the world, resulting in potentially millions of animals disappearing from scientific studies.
“I think it’s just outrageous that we have such a low rate of results published for the number of animals used”, says Michael Schlüssel, a medical statistician at the University of Oxford who was not involved in the study. “If we only look for groundbreaking research, the evidence base won’t be solid”, he adds. And that could impact studies that may confirm or refute the benefits of certain drugs or medical interventions.
…For the new study, researchers asked scientists at three University Medical Center Utrecht (UMCU) departments for permission to review the study protocols they had filed with an animal ethics committee in 2008 and 2009. (They picked those years in part to be completely sure that the scientists had plenty of time to conduct and report the studies.) Then the team—led by Mira van der Naald, a doctoral student at UMCU—searched the medical literature for papers resulting from the work.
Of the approved studies, 46% were published as a full-text paper; if conference abstracts—short summaries of a talk or poster presented at a scientific meeting—were counted as well, 60% ended up being published. Yet out of the 5590 animals used in the studies, only 1471 were acknowledged in published papers and abstracts, the team reports in BMJ Open Science. Small animals, including mice, rats, and rabbits—which made up 90% of the total—were most often missing in action: Only 23% of them showed up in publications, versus 52% of sheep, dogs, and pigs.
The researchers also surveyed the scientists involved to find out why so many animals were missing. The most common reasons they gave were that the studies didn’t achieve statistical-significance, a controversial but commonly used threshold for publication; that the data were part of a pilot project; and that there were technical issues with the animal models. But none of these is a valid excuse to not publish your findings in the scientific record, says study co-author Kimberley Wever, a metascientist at Radboud University Medical Center. “All animal studies should be published, and all studies are valuable for the research community.” Not publishing all research means other scientists may waste time, effort, and money redoing studies that have previously failed, Wever says. She adds that the trend likely holds up at institutions around the world and hopes other researchers will conduct similar studies.