Use of the General Practice Research Database (GPRD) for respiratory epidemiology: a comparison with the 4th Morbidity Survey in General Practice (MSGP4)

摘要

BACKGROUND—The GeneralPractice Research Database (GPRD) covers over 6% of the population ofEngland and Wales and holds data on diagnoses and prescribing from 1987 onwards. Most previous studies using the GPRD have concentrated on druguse and safety. A study was undertaken to assess the validity of usingthe GPRD for epidemiological research into respiratory diseases.
METHODS—Age-specificand sex-specific rates derived from the GPRD for 11 respiratoryconditions were compared with patient consultation rates from the 4thMorbidity Survey in General Practice (MSGP4). Within the GPRDcomparisons were made between patient diagnosis rates, patientprescription rates, and patient "prescription plus relevantdiagnosis" rates for selected treatments.
RESULTS—There was goodagreement between consultation rates in the MSGP4 and diagnosis or"prescription plus diagnosis" from the GPRD in terms of pattern andmagnitude, except for "acute bronchitis or bronchiolitis" where thebest comparison was the combination category of "chest infection"and/or "acute bronchitis or bronchiolitis". Within the GPRD,patient prescription rates for inhalers, tuberculosis or hayfevertherapy showed little similarity with diagnosis only rates but asimilarity was seen with the combination of "prescription plusdiagnosis" which may be a better reflection of morbidity thandiagnosis alone.
CONCLUSIONS—The GPRDappears to be valid for primary care epidemiological studies bycomparison with MSGP4 and offers advantages in terms of large size, alonger time period covered, and ability to link prescriptions withdiagnoses. However, careful interpretation is needed because not allconsultations are recorded and the coding system used contains termswhich do not directly map to ICD codes.