A scoping review on reporting of methods in DSS colitis mouse models.

Inflammatory bowel diseases (IBDs) are a major health burden, and incidence as well as prevalence have increased over the last decades. Colitis animal models are used to explore the underlying pathogenesis of and therapeutic options for IBD. Since the reporting of specific aspects of colitis studies using mice has been criticized in the past, we performed a scoping review based on the PRISMA guidelines to assess putative improvements in the quality of reporting. A defined search for dextran sulfate sodium (DSS) murine colitis models was performed in three literature databases (PubMed, PubMed Central®, and Embase) for two time periods: 2007/2008 and 2017. Data were extracted from 122 articles published in 2007/2008 and 236 publications from 2017. We checked the articles for the reporting of details of the colitis model (DSS properties, manufacturer, concentration, duration of application, mouse strain, sex, source), measures to reduce allocation, performance and detection bias (randomization and blinding), and information on clinical assessment, refinements, and humane endpoints. Our results showed that there was significant improvement over time in the scores for refinement and, based on this, also the completeness score. However, the other aspects were poorly reported, suggesting that this research field may need to adopt reporting guidelines such as ARRIVE, the Gold Standard Publication Checklist, or the colitis methods checklist when writing and reviewing publications.