Back to Browse Journals » Therapeutics and Clinical Risk Management » Volume 3 » Issue 4

How should we measure medication adherence in clinical trials and practice?

Authors Jeannie K Lee, Karen A Grace, Terri G Foster, Monica J Crawley, Goldina I Erowele, et al

Published Date October 2007 Volume 2007:3(4) Pages 685—690

DOI http://dx.doi.org/

Published 4 October 2007

Jeannie K Lee, Karen A Grace, Terri G Foster, Monica J Crawley, Goldina I Erowele, Hazel J Sun, Phuong T Turner, Lance E Sullenberger, Allen J Taylor

Pharmacy and Cardiology Services, Walter Reed Army Medical Center, Washington, DC, USA

Objective: To determine if simple adherence measures, such as twenty-four hour recall and refill history, are accurate for routine use, compared to more time-consuming measures such as pill counts.

Design: Randomized, double-blind, placebo-controlled trial.

Setting: Walter Reed Army Medical Center, a tertiary medical center in Washington.

Patients: Men and women >30 years old with known coronary heart disease and taking a statin medication.

Intervention: Clinical pharmacists met with patients for adherence assessments.

Main outcome measures: Adherence was measured by pill counts, twenty-four hour recall by patient, and refill history per computer record. Temporal changes in these adherence measures were assessed using general linear models for repeated measures.

Results: Adherence was consistently greater for the experimental agent than for the statin therapy (n = 148). Mean pill count adherence for statin drug was 78.7 ± 25.2% compared to 93.5 ± 11.6% (P < 0.001) for the study agent. Refill history and twenty-four hour recall inaccurately measured adherence when compared to pill counts. Adherence, as determined by pill count, for both experimental (P = 0.029) and statin therapy (P = 0.015) showed significant variability across time in general linear models. Neither refill history nor twenty-four hour recall was sensitive to temporal changes.

Conclusions: Twenty-four hour recall and refill history inaccurately measure medication adherence for both clinical trial and clinical practice pharmacotherapies. Further, these measures are insensitive to changes in adherence. For a single or multiple assessments across time, pill count more accurately measures medication adherence. Pill count should be the standard for monitoring medication adherence for both clinical trials and clinical practice.

Keywords: adherence, hyperlipidemia, niacin, pharmacist, pill count, simvastatin

Download Article [PDF] 

Readers of this article also read:

Disruption of human papillomavirus 16 E6 gene by clustered regularly interspaced short palindromic repeat/Cas system in human cervical cancer cells [Corrigendum]

Yu L, Wang XL, Zhu D, Ding WC, Wang LM, Zhang CL, Jiang XH, Shen H, Liao SJ, Ma D, Hu Z, Wang H

OncoTargets and Therapy 2015, 8:365-366

Published Date: 4 February 2015

An anthropometric study to evaluate the correlation between the occlusal vertical dimension and length of the thumb

Basnet BB, Parajuli PK, Singh RK, Suwal P, Shrestha P, Baral D

Clinical, Cosmetic and Investigational Dentistry 2015, 7:33-39

Published Date: 3 February 2015

Corrigendum

Basit A, Riaz M, Fawwad A

Vascular Health and Risk Management 2013, 9:1-2

Published Date: 27 December 2012

Corrigendum

De Caterina AR, Harper AR, Cuculi F

Vascular Health and Risk Management 2012, 8:443-445

Published Date: 19 July 2012

Role of aliskiren in cardio-renal protection and use in hypertensives with multiple risk factors

Eduardo Pimenta, Suzanne Oparil

Vascular Health and Risk Management 2009, 5:453-463

Published Date: 19 May 2009