(23) Validation of a Cohort of Rheumatoid Arthritis (RA) Patients in CPRD Aurum

Publication Number: 697

Background: CPRD GOLD and CPRD Aurum are sourced from the same UK health care system but use different software platforms. Unlike the Vision patient management software that supports CPRD GOLD, CPRD Aurum uses EMIS, which was not developed with the intent to provide data for medical research. CPRD Aurum is now much larger than CPRD GOLD and has the potential to be a valuable source of data.

Objectives: Evaluate data recorded in CPRD Aurum compared to CPRD GOLD as a critical step towards making decisions about its suitability for use in medical research.

Methods: A study of quality of recording of rheumatoid arthritis (RA) diagnoses, labs, and treatments in the new CPRD Aurum database, compared to the CPRD GOLD database. Using NICE guidelines, we selected relevant indicators of RA diagnosis, treatment, and management. We included all patients in England in CPRD Aurum and CPRD GOLD with an incident diagnosis of RA on or after 1 January 2005, at least 2 years after registration.

Results: We found 53,083 and 18,167 patients with a new diagnosis of RA in CPRD Aurum and CPRD GOLD, respectively. In both databases approximately 67% were female with similar mean ages at first diagnosis. Before first RA diagnosis, CPRD Aurum patients were more likely to have more RA specific labs recorded at any time, and more supporting codes recorded. After diagnosis, CPRD Aurum patients were more likely to have 2 or more diagnoses of RA recorded and 10 or more general RA labs recorded, and patients in CPRD GOLD were more likely to have 10 or more prescriptions for conventional disease-modifying antirheumatic drugs (cDMARD). Otherwise, the distribution of drugs used to treat RA was similar between databases. The standardized incidence of RA was similar between databases. Correctness appeared somewhat higher in CPRD Aurum compared to CPRD GOLD.

Conclusions: Overall, among RA patients, recording of diagnoses, prescription drugs and labs were similar between CPRD Aurum and CPRD GOLD. Slight differences were found for a few variables under study, but overall, we found consistency between the databases. In addition, standardized incidence of RA was similar between databases. This validation study provides assurance of the quality of the new Aurum database that, given its size, could play an important role in health research.