Systematic review and meta-analysis of preclinical studies

The preclinical research community faces an ever-expanding corpus of biomedical literature, making it challenging to keep abreast with the latest findings. This hampers evidence-based research and informed decision-making. Thus, reliable tools are warranted to manage this evidence and maximize the global investment in research. Systematic reviews, syntheses of existing scientific evidence that address a focused question in an unbiased manner and using explicit methods, have gained momentum as an effective solution. Systematic reviews have an important role in uncovering problems in preclinical research, informing best practice guidelines, reducing research waste, promoting reproducibility and guiding translational research. Systematic reviews of preclinical studies also promote ethical animal use by maximizing the use of existing animal studies, thereby fostering animal welfare. However, poorly performed systematic reviews can produce unreliable results, leading to incorrect conclusions about the underlying literature. This Primer presents guidance for conducting a rigorous systematic review with or without meta-analysis of preclinical studies including animal and in vitro studies. It also discusses the limitations of systematic reviews and outlines current developments such as systematic review automation. By following this Primer, researchers can ensure the rigour and usefulness of their systematic reviews, ultimately benefiting decision-making and research outcomes in preclinical research. Preclinical systematic reviews look at scientific evidence addressing focused questions from animal research studies to inform future clinical research. In this Primer, Ineichen et al. discuss the best practices for conducting preclinical systematic reviews, promoting reproducibility and guiding translational research.