Bias in the reporting of sex and age in biomedical research on mouse models

Lack of accurate method reporting is one of the primary causes of irreproducibility in biomedical research. In animal-based biomedical research, both sex and age affect the disease phenotypes; modifying their susceptibility, presentation and response to treatment. Here we look at these two variables by using text-mining across available full text articles that report investigations where mice were the focus of the study. We found that, although there is an improvement during the last two decades, the lack of reporting of these variables is still a concern; only about 50% of the papers published in 2014 stated these variables. In addition, we observed a sex-bias variability according to the field of study. We hope that this text-mining strategy can be taken as a starting point for future more focused assessment of literature, both in preclinical and clinical studies, and thus impact on the reproducibility of findings and on future study validity.