These consider some of the issues relating to the use of animals in biomedical research:
Unfortunately not. There is good evidence that only a few animal researchers are aware of the many ways in which their experiments can be biased (Reichlin et al 2016) and that only a few researchers take steps to minimise the possibility of these biases (Kilkenny et al 2009). For example only a minority of animal researchers allocate animals to study groups randomly (Hirst et al 2014; Macleod et al 2015; Henderson et al 2015) with the result that unconscious bias creeps in. Studies that do not use random allocation are more likely to report positive findings (Bebarta et al 2003; Hirst et al 2014). Another way in which bias can be introduced is when the person assessing the outcomes of an experiment is aware which group received the experimental treatment. This is a problem in animal research (Henderson et al 2015; Bebarta et al 2003; Perel et al 2007; Kilkenny et al 2009; Hirst et al 2014; Macleod et al 2015); studies in which the researcher assessing outcomes knew which group received the experimental treatment were more likely to report positive findings (Bebarta et al 2003; Vesterinen et al 2010).
Furthermore, simplistic statistical analyses are often used that do not account for factors such as the age or sex of the animals. Not taking such factors into account may alter the results of experiments. For example there are at least 50 publications describing drugs that extend the lives of mice with motor neurone disease. Researchers identified factors (such as age and sex) that might have altered this body of research and then repeated the experiments, this time correctly taking account of such factors. They found that none of the drugs now extended the mice’s lives and concluded that the original positive findings were unlikely to have been due to the effect of the experimental drugs, but were most likely due to the experiments not being conducted properly (Scott et al 2008).
As a result of the lack of scientific rigour in animal research, it can be seen that large bodies of animal research report positive findings that are not actually real, but that are a function of poorly designed experiments. At present most animal research is of such poor quality that no reliable conclusions may be drawn from it. This wastes animals’ lives, squanders research funding and endangers humans who participate in clinical trials that are based on misleading animal data.