Data Format

The data collected from general practices are held within a relational SQL database (with multiple rows of data allowable per patient) in 6 raw files:

  • Patient Data – patient demographics
  • Clinical Data – medical history pertaining to a selection of clinical records defined by a compiled list of Read codes.
  • Therapy Data – details of prescriptions for drugs issued by GPs. Drug codes are based on British National Formulary (BNF) codes (to be replaced by SNOMED in 2018)
  • Referral Data – referrals to external care centres e.g. secondary care locations/hospitals and reasons for referral information
  • Practice Data – contains practice administration information
  • Questionnaire Data – contain anonymous patient questionnaire records for child asthma, adult asthma and COPD

Presently, all data in the database are coded using Read coding system. However, along with all other healthcare services in the UK OPCRD will transfer from Read Codes to the SNOMED CT system for clinical terminology by April 2018.

More information on the structure and content of the data is accessible from the OPCRD Technical Workbook.