Reports of hundreds of biomedical experiments lack essential information.
Whereas reports of clinical trials in major medical journals routinely state how many patients die or drop out of analysis during the course of a study, animal studies generally fail to report this figure — or drop animals without saying why, according to a team led by Ulrich Dirnagl at the Charité Medical University in Berlin. That lapse could significantly bias results, the team reports in the journal PLoS Biology.
Dirnagl’s team reviewed 100 reports published between 2000 and 2013 describing 522 experiments that used rodents to test cancer and stroke treatments, and compared the numbers of animals reported in the papers’ methods and results sections. Some two-thirds of the experiments did not state whether they had dropped any animals from their final analysis. Of those that did report numbers, around 30% (53 experiments) reported that they had dropped rodents from their study analysis, but only 14 explained why. More.
“You stick your hand in a cage, and pull out a rat,” Ian Roberts, a professor of epidemiology at the London School of Hygiene and Tropical Medicine, told The Scientist. “The rats that are the most vigorous are hardest to catch, so when you pull out 10 rats, they’re the sluggish ones, the tired ones, they’re not the same as the ones still in the cage, and they’re the control.
With your coffee … We thought we were playing with the mice, but maybe they were playing with us. A racket run by King Rat? 😉
See also: Mice studies often meaningless for humans? Researcher: “Animal models are limited in their ability to mimic the extremely complex process of human carcinogenesis, physiology and progression.”
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