title: Standardizing terminology and definitions of medication adherence and persistence in research employing electronic databases.
abstract: OBJECTIVE
  To propose a unifying set of definitions for prescription adherence research utilizing electronic health record prescribing databases, prescription dispensing databases, and pharmacy claims databases and to provide a conceptual framework to operationalize these definitions consistently across studies.
  
  
  METHODS
  We reviewed recent literature to identify definitions in electronic database studies of prescription-filling patterns for chronic oral medications. We then develop a conceptual model and propose standardized terminology and definitions to describe prescription-filling behavior from electronic databases.
  
  
  RESULTS
  The conceptual model we propose defines 2 separate constructs: medication adherence and persistence. We define primary and secondary adherence as distinct subtypes of adherence. Metrics for estimating secondary adherence are discussed and critiqued, including a newer metric (New Prescription Medication Gap measure) that enables estimation of both primary and secondary adherence.
  
  
  CONCLUSIONS
  Terminology currently used in prescription adherence research employing electronic databases lacks consistency. We propose a clear, consistent, broadly applicable conceptual model and terminology for such studies. The model and definitions facilitate research utilizing electronic medication prescribing, dispensing, and/or claims databases and encompasses the entire continuum of prescription-filling behavior.
  
  
  CONCLUSIONS
  Employing conceptually clear and consistent terminology to define medication adherence and persistence will facilitate future comparative effectiveness research and meta-analytic studies that utilize electronic prescription and dispensing records.
authors.affiliation: Kaiser Permanente Colorado Institute for Health Research, Denver, CO 80231, USA. marsha.a.raebel@kp.org
authors.forename: Marsha A
authors.initials: MA
authors.lastname: Raebel
authors.forename: Julie
authors.initials: J
authors.lastname: Schmittdiel
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Karter
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Konieczny
authors.forename: John F
authors.initials: JF
authors.lastname: Steiner
mesh_terms: D016208:Databases, Factual / Q000706:statistics & numerical data; D057286:Electronic Health Records / Q000458:organization & administration* / Q000706:statistics & numerical data*; D006302:Health Services Research; D006801:Humans; D007345:Insurance Claim Review / Q000706:statistics & numerical data; D015337:Multicenter Studies as Topic / Q000706:statistics & numerical data; D010593:Pharmaceutical Services / Q000706:statistics & numerical data; D009626:Terminology as Topic; D016903:Drug Monitoring