Fig. 1

Details of the observation period of the included knee OA patients. Note. This figure shows details of the observation period of the included knee OA patients. Patients aged ≥ 30 with a first knee OA diagnosis (i.e. incident) between 1 July 2011 and 31 December 2016 and valid database history of at least 12 months prior to study entry were included in the study cohort. Patients were required to have at least three years of observation time after the index date, as pilot testing showed that most GP consultations for knee OA occurred within this period. Information was extracted from the full EHRs on the GP’s management at each consultation in this period from six months before the index date to three years after the index date