Dickersin and Min define publication bias as the failure to publish the results of a study ‘on the basis of the direction or strength of the study findings’. This non-publication introduces a bias which impacts the ability to accurately synthesise and describe the evidence in a given area. Publication bias is a type of reporting bias and closely related to dissemination bias, although dissemination bias generally applies to all forms of results dissemination, not simply journal publications. To read the full article, log in using your NHS OpenAthens details.