AbstractPurposeWhile several studies have assessed quality and completeness of recording acute medical events in Clinical Practice Research Datalink (CPRD) Aurum, evaluation of additional chronic conditions is warranted.MethodsWe selected patients with a first diagnosis of rheumatoid arthritis (RA) coded in their CPRD Aurum record between 2005 and 2019. We assessed quality of RA diagnosis by evaluating additional information in the patient record that would corroborate the diagnosis. We report recording of diagnoses, prescriptions, labs, and referrals expected to be present based on NICE guidelines for RA management.ResultsThere were 53 083 patients with a first recorded RA diagnosis during the study period: 43606 (82%) patients had RA drug treatments in their record, 7596 (14%) had supporting codes without drug treatment, and 1881 (4%) patients had only a RA diagnoses recorded in their medical record with no supporting codes or RA treatments. Patients with RA diagnosis only were more likely to be first diagnosed in the earliest time period of study. Labs for diagnosing and monitoring RA were most common among patients with RA treatment. Analgesic and glucocorticoid prescriptions were common in all study patients but were highest among patients with RA treatment. Among patients with RA diagnosis only, the overwhelming majority had only one RA diagnosis recorded (76%).ConclusionsOur findings suggest that codes expected for monitoring and treatment of RA are routinely recorded in CPRD Aurum. These results support previous assessments, which found data recorded in CPRD Aurum to be of good quality for use in research.