It was set up in 2002 by Professor Julia Hippisley-Cox with EMIS Health (a leading commercial supplier of GP computer systems for over 55% of UK practices). QResearch is the largest database of its kind in the UK and one of the largest databases of its kind worldwide. It includes longitudinal data spanning more than 30 years which is updated regularly. GP data is linked at individual patient level to Hospital Episode Statistics (HES), civil registry, cancer registry, Intensive Care National Audit & Research Centre (ICNARC), Public Health England (PHE) Second Generation Surveillance System (SGSS) COVID-19 test results, ONS occupation data, and COVID-19 vaccination data from the National Immunisation Database making it an extremely rich resource for epidemiology-related research. QResearch is a non-profit collaboration between University of Oxford and EMIS and is aiming to facilitate access to health care records for research purposes.