This study links data from the UK Renal Registry and the Intensive Care National Audit and Research Centre (ICNARC) which holds the National Cardiac Arrest Audit (NCAA) database. By linking data from the two registries, we will have a dataset of people receiving dialysis or living with a transplant who experienced cardiopulmonary resuscitation (CPR) in hospital. We will be able to analyse these data to see how many people receiving dialysis or living with a transplant in England receive CPR in hospital each year, and how well they do after the CPR, for example how long do they live for and what their crude level of functioning is when they leave hospital, and how this changes based on factors such as their age or sex. This information will help doctors, patients, and their loved ones make advance care planning decisions based on up to date information that is relevant to them.