title: Development and validation of an instrument to assess treatment adherence for each individual drug taken by a patient.
abstract: To develop and validate an instrument to assess adherence to each individual drug taken by patients undergoing long-term treatment.
  
  
  
  Multicentre prospective observational validation study.
  
  
  
  Six general practitioners' clinics and 6 university hospitals in Paris, France.
  
  
  
  Patients 18 years and older receiving at least one long-term treatment.
  
  
  
  The instrument was developed from a literature search and interviews with experts. Clarity and wording were assessed during pilot testing with 51 patients. The tool was validated in a sample of consecutive patients. We assessed agreement between adherence measured with our tool and drug diaries and compared measurements from our instrument with (1) the Lu instrument; (2) the Adherence Estimator (AE); (3) patient's adherence assessed by physicians; (4) the Morisky Medication Adherence Scale-4 items (MMAS-4); and (5) the Treatment Burden Questionnaire (TBQ). Reliability was assessed by a test-retest method.
  
  
  
  A total of 243 patients taking 961 drugs were recruited in 2014. We found good agreement between adherence measured by our tool and drug diaries (intraclass correlation coefficient (ICC) 0.69, 95% CI 0.34 to 0.91) and a linear relationship between measurement with our tool and (1) the Lu instrument (p<0.01); (2) 2 items of the AE (perceived need for medication (p<0.01) and concerns about medication (p<0.01)); (3) patients' adherence assessed by their physicians (p<0.01); (4) the MMAS-4 (p<0.01) and (5) the TBQ (p<0.01). Reliability of the retest was good (ICC 0.67, 95% CI 0.42 to 0.85).
  
  
  
  We developed an instrument with acceptable validity and reliability to assess adherence for each drug taken by patients, usable in hospital and primary care settings.
authors.affiliation: Department of General Medicine, Paris Descartes University, Paris, France METHODS Team, Epidemiology and Statistics Sorbonne Paris Cité Research Centre, UMR 1153, INSERM, Paris, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Sidorkiewicz
authors.affiliation: METHODS Team, Epidemiology and Statistics Sorbonne Paris Cité Research Centre, UMR 1153, INSERM, Paris, France Department of General Medicine, Paris Diderot University, Paris, France.
authors.forename: Viet-Thi
authors.initials: VT
authors.lastname: Tran
authors.affiliation: Department of General Medicine, Paris Diderot University, Paris, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Cousyn
authors.affiliation: METHODS Team, Epidemiology and Statistics Sorbonne Paris Cité Research Centre, UMR 1153, INSERM, Paris, France.
authors.forename: Elodie
authors.initials: E
authors.lastname: Perrodeau
authors.affiliation: METHODS Team, Epidemiology and Statistics Sorbonne Paris Cité Research Centre, UMR 1153, INSERM, Paris, France French Cochrane Centre, Paris, France Department of Epidemiology, Mailman School of Public Health, Columbia University, New York City, USA.
authors.forename: Philippe
authors.initials: P
authors.lastname: Ravaud
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005602:France; D006801:Humans; D008134:Long-Term Care / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D016903:Drug Monitoring
keywords: GENERAL MEDICINE (see Internal Medicine); PRIMARY CARE; medication adherence; questionnaire; validity