BILM’s Clinical Knowledge Summaries (CKS) are evidence summaries on longevity medicine topics, written for UK doctors and other healthcare professionals. Each summary sets out the evidence for a test or intervention, grades its certainty (high, moderate, low or very low) and states whether a use is guideline-based, off-label or research-only. Where a summary departs from NICE guidance, the aim is to say so and explain why. The summaries support clinical judgement and shared decision-making. They do not replace NICE guidance, product licences or individual clinical assessment, and they are not advice for patients: anyone considering a test or treatment should discuss it with their own doctor.