title: Is real world evidence influencing practice? A systematic review of CPRD research in NICE guidances.
abstract: There is currently limited evidence regarding the extent Real World Evidence (RWE) has directly impacted the health and social care systems. The aim of this review is to identify national guidelines or guidances published in England from 2000 onwards which have referenced studies using the governmental primary care data provider the Clinical Practice Research Datalink (CPRD).
  
  
  
  The methodology recommended by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was followed. Four databases were searched and documents of interest were identified through a search algorithm containing keywords relevant to CPRD. A search diary was maintained with the inclusion/exclusion decisions which were performed by two independent reviewers.
  
  
  
  Twenty-five guidance documents were included in the final review (following screening and assessment for eligibility), referencing 43 different CPRD/GPRD studies, all published since 2007. The documents covered 12 disease areas, with the majority (N =7) relevant to diseases of the Central Nervous system (CNS). The 43 studies provided evidence of disease epidemiology, incidence/prevalence, pharmacoepidemiology, pharmacovigilance and health utilisation.
  
  
  
  A slow uptake of RWE in clinical and therapeutic guidelines (as provided by UK governmental structures) was noticed. However, there seems to be an increasing trend in the use of healthcare system data to inform clinical practice, especially as the real world validity of clinical trials is being questioned. In order to accommodate this increasing demand and meet the paradigm shift expected, organisations need to work together to enable or improve data access, undertake translational and relevant research and establish sources of reliable evidence.
authors.affiliation: Clinical Practice Research Datalink (CPRD), Medicines and Healthcare products Regulatory Agency, 151 Buckingham Palace Road, Victoria London, SW1W 9SZ, UK. Jessie.Oyinlola@mhra.gsi.gov.uk.
authors.forename: Jessie O
authors.initials: JO
authors.lastname: Oyinlola
authors.affiliation: Clinical Practice Research Datalink (CPRD), Medicines and Healthcare products Regulatory Agency, 151 Buckingham Palace Road, Victoria London, SW1W 9SZ, UK.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Campbell
authors.affiliation: Clinical Practice Research Datalink (CPRD), Medicines and Healthcare products Regulatory Agency, 151 Buckingham Palace Road, Victoria London, SW1W 9SZ, UK.
authors.forename: Antonis A
authors.initials: AA
authors.lastname: Kousoulis
mesh_terms: D035843:Biomedical Research; D002908:Chronic Disease / Q000628:therapy*; D016208:Databases, Factual; D004739:England; D019317:Evidence-Based Medicine; D006801:Humans; D033181:Information Dissemination; D017410:Practice Guidelines as Topic; D011364:Professional Practice / Q000639:trends*
keywords: Clinical practice research datalink; Guidance; Real world evidence