NCT03743883 - EffectiveNess of Low-dose Aspirin in Prevention of Cancer in the Stomach and Oesophagus (GastrointEstinal Cancer Prevention) - United Kingdom ("ENgAGE - UK"): Study to Evaluate the Risk of Cancer in the Stomach and Oesophagus Among New Users of Low-dose Aspirin Using the THIN Database in the UK | Crick | Crick