Reporting and design standards are key indicators of the quality of diagnostic accuracy (validation) studies but, with the exception of aquatic animal diseases and paratuberculosis in ruminants, there is limited guidance for designing these studies in animals. There is, therefore, a need for generic guidelines that are based on disease characteristics, such as mode of transmission, latent period and pathogenesis. Comprehensive, clear and transparent reporting of primary test accuracy studies for diseases listed by the World Organisation for Animal Health (OIE) has value for the end users of diagnostic tests and, ultimately, for decision-makers, who require systematic reviews and meta-analysis of multiple tests for specified diseases and testing purposes. The recent publication of reporting standards for Bayesian latent class models, to analyse test-accuracy data from naturally occurring disease events, fills an important gap as these methods are being increasingly used for OIE-listed diseases. Adherence to design and reporting standards, as well as to guidelines, helps to ensure that research funding for test validation studies is used appropriately and that the strengths and limitations of single tests or test combinations are made clear to test users. The authors provide a review of key points that are often overlooked or misinterpreted in test validation studies, as well as two concrete examples of good practice for use as a reference point for future studies.