title: Assessing medication adherence: options to consider.
abstract: BACKGROUND
  Adherence to chronic therapy is a key determinant of patient health outcomes in chronic disease. However, only about 50 % of patients adhere to chronic therapy. One of the challenges in promoting adherence is having an accurate understanding of adherence rates and the factors that contribute to non-adherence. There are many measures available to assess patient medication adherence.
  
  
  OBJECTIVE
  This review aims to present the commonly used indirect methods available for measuring medication adherence in routine healthcare and research studies.
  
  
  METHODS
  A literature review on medication adherence measures in patient populations with chronic conditions taking chronic medications was conducted through Medline (2003-2013). A complementary manual search of references cited in the retrieved studies was performed in order to identify any additional studies.
  
  
  RESULTS
  Of the 238 initial Medline search results, 57 full texts were retrieved. Forty-seven articles were included as a result of the manual search. Adherence measures identified were: self-report (reported in 50 publications), electronic measures (33), pharmacy refills and claims data (26) and pill counts (25). Patient self-report, electronic measures, pharmacy refill and claims data were the most commonly used measures of adherence in research, routine practice, epidemiological and intervention studies. These methods, and their strengths and limitations have been described in this paper.
  
  
  CONCLUSIONS
  A multitude of indirect measures of adherence exist in the literature, however, there is no "gold" standard for measuring adherence to medications. Triangulation of methods increases the validity and reliability of the adherence data collected. To strengthen the adherence data collected and allow for comparison of data, future research and practice interventions should use an internationally accepted, operational standardized definition of medication adherence and clearly describe the medication adherence methods used.
authors.affiliation: Univ. Grenoble-Alpes, 38041, Grenoble, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Lehmann
authors.forename: Parisa
authors.initials: P
authors.lastname: Aslani
authors.forename: Rana
authors.initials: R
authors.lastname: Ahmed
authors.forename: Jennifer
authors.initials: J
authors.lastname: Celio
authors.forename: Aurelie
authors.initials: A
authors.lastname: Gauchet
authors.forename: Pierrick
authors.initials: P
authors.lastname: Bedouch
authors.forename: Olivier
authors.initials: O
authors.lastname: Bugnon
authors.forename: Benoît
authors.initials: B
authors.lastname: Allenet
authors.forename: Marie Paule
authors.initials: MP
authors.lastname: Schneider
mesh_terms: D002908:Chronic Disease; D004363:Drug Utilization / Q000706:statistics & numerical data; D057286:Electronic Health Records; D006801:Humans; D007356:Insurance, Pharmaceutical Services; D057566:Self Report; D016903:Drug Monitoring