Recent results of the NELSON Lung Cancer Screening Trial reports reductions in lung-cancer survival but not overall survival - The desire to detect disease even earlier means Overdiagnosis is on the rise. However, the interpretation of screening trial results is problematic and often gives rise to significant uncertainties that go unanswered.\n\nCarl Heneghan, Professor of Evidence-Based Medicine, employs evidence-based methods to research diagnostic reasoning, test accuracy and communicating diagnostic results to a wider audience.\n\nThis talk was held as part of the Evidence-Based Diagnosis and Screening module which is part of the MSc in Evidence-Based Health Care and the MSc in EBHC Medical Statistics.