CPRD: An introduction to the Clinical Practice Research Datalink in Cambridge Rupert Payne

What is CPRD? Governmental, not-for-profit research service Funded by NIHR and MHRA VAMP Research (1987)  GPRD (1993)  CPRD (2012) Provides anonymous general practice health records for public health research, with linkage to additional non-primary care data University has annual institutional license to online access of data Managed through Primary Care Unit Funded by specific projects with additional support from BRC

Primary care data collection Primary care data collected from Vision GP clinical software Data are recorded as part of routine clinical practice Coded data, free text Practices assessed for quality of data recording Feedback provided to GPs to improve/standardise recording Data anonymised at practice, then uploaded to CPRD servers for processing and validation Anonymised routine GP data since 1987, extracted from the Vision system, more recently EMIS, covering 8% of the UK population. Novel linkages can be done and CPRD has systems for facilitating clinical trials

The CPRD population 7% sample of UK population 5 million “active” patients 674 Vision practices Mean practice list size: CPRD=8400, UK=6600 CPRD population 2014 UK population Ambition is to get all patients in UK. Currently only Vision practices included. Active=live and registered

Overview of primary care data Patient – demographics, registration Practice – region, collection information Consultations – date, duration Clinical – diagnoses, administrative details Therapy – electronic prescribing Immunisation – vaccination details Referrals – to secondary care Tests – lab results, other measures Staff – staff type Surveys Biological samples Embedded trials

Linkages to other data Admitted Patient Care Hospital Episode Statistics (HES) Outpatient Hospital Episode Statistics (HES) Death Registration Data (Office for National Statistics, ONS) Cancer registry data (Public Health England) Cardiovascular registry data (Myocardial Ischaemia National Audit Project, MINAP) On-going linkage: e.g. mental health (MHMDS), HES A&E, digital imaging …plus additional bespoke linkages if required

How well are things recorded? Ambition is to get all patients in UK. Currently only Vision practices included Herrett, Int J Epidemiol 2015

CPRD clients Academia Pharmaceutical industry Government

Research that can be done with CPRD Medication and devices Drug utilisation, compliance and persistence Pharmacovigilance Pharmacoepidemiology Pharmacoeconomics Life cycle planning Licence extension research Health care interventions Comparative effectiveness research Outcomes Clinical outcomes Patient Reported Outcomes Public health research Epidemiology Health Services research Risk management research Risk-benefit research Risk score development Clinical trials Randomisation at point of care Phase 3 and 4 trials CPRD observational data resources and services Disease and drug registers Pan European and US data

Publications using CPRD Based on search of PubMed for CPRD and GPRD

Cambridge work using CPRD Work led by Autism Research Centre Women with polycystic ovarian syndrome, and their children, have a greater prevalence of autism OR 1.58 (1.27-1.98) OR 1.90 (1.32-2.72) Baron-Cohen, unpublished data

Cambridge work using CPRD MPhil student project Association between service utilisation and multimorbidity in persons with dementia Browne, unpublished data

Cambridge work using CPRD Long-term outcomes of survivors of critical care Novel linkage of CPRD and ICNARC-CMP Pharmacoeconomics of iron salts utilisation Supporting novel drug development Medication use in end of life care patients

Challenges of using CPRD Messy data Big data Code lists diabetes codes

Independent Scientific Advisory Committee (ISAC) “To consider and provide advice to MHRA on … all research projects which propose the use of data obtained from the Clinical Practice Research Datalink” Advises on medical, statistical, epidemiological and methodological aspects Ensures no governance concerns All protocols to use data must be first approved by ISAC Protocols should adhere to IPSE Good Pharmacoepidemiology Practices Some studies may also require other committee approval (e.g. HRA Confidentiality Advisory Group, HSCIC Data Access Advisory Group) International Society for Pharmacoepidemiology (ISPE), HRA=Health Research Authority

Core CPRD team James Brimicombe Duncan Edwards Amelia Harshfield Rupert Payne Kirsty Rhodes