BetterRx utilises primary care electronic health records of frail and elderly (65 years+) people in the UK; containing basic patient demographics such as year of birth, sex, ethnicity, BMI and smoking history. The dataset includes medical history to identify known health conditions (e.g. diabetes diagnosis), prescription history to identify all known prescribed medications over time, linked outcomes as defined in the primary care record, hospital episode statistics (HES) and mortality (ONS), linked area deprivation defined using linked practice and patient level index of multiple deprivation (IMD). The temporal start date of GP data varies by practice, two year historic data at the point of sign up.