Journal of General Internal Medicine

, Volume 24, Issue 5, pp 570–578 | Cite as

Can Improved Prescription Medication Labeling Influence Adherence to Chronic Medications? An Evaluation of the Target Pharmacy Label

  • William H. ShrankEmail author
  • Patrick P. Gleason
  • Claire Canning
  • Carol Walters
  • Alan H. Heaton
  • Saira Jan
  • Amanda Patrick
  • M. Alan Brookhart
  • Sebastian Schneeweiss
  • Daniel H. Solomon
  • Jerry Avorn
  • Niteesh K. Choudhry
Original Article



Prescription medication labels contain valuable health information, and better labels may enhance patient adherence to chronic medications. A new prescription medication labeling system was implemented by Target pharmacies in May 2005 and aimed to improve readability and understanding.


We evaluated whether the new Target label influenced patient medication adherence.


Using claims from two large health plans, we identified patients with one of nine chronic diseases who filled prescriptions at Target pharmacies and a matched sample who filled prescriptions at other community pharmacies.


We stratified our cohort into new and prevalent medication users and evaluated the impact of the Target label on medication adherence. We used linear regression and segmented linear regression to evaluate the new-user and prevalent-user analyses, respectively.


Our sample included 23,745 Target users and 162,368 matched non-Target pharmacy users. We found no significant change in adherence between new users of medications at Target or other community pharmacies (p = 0.644) after implementing the new label. In prevalent users, we found a 0.0069 percent reduction in level of adherence (95% CI −0.0138-0.0; p < 0.001) and a 0.0007 percent increase in the slope in Target users (the monthly rate of change of adherence) after implementation of the new label (95% CI 0.0001–0.0013; p = 0.001).


We found no changes in adherence of chronic medication in new users, and small and likely clinically unimportant changes in prevalent users after implementation of the new label. While adherence may not be improved with better labeling, evaluation of the effect of labeling on safety and adverse effects is needed.


label prescription medication adherence 



This work was supported by a Pioneer Award from the Robert Wood Johnson Foundation.

Dr. Shrank is supported by a career development award from the National Heart, Lung and Blood Institute (K23HL090505-01). Dr. Brookhart is supported by a career development award from the National Institute of Aging (AG-027400).

Drs. Shrank, Avorn, Choudhry, Schneeweiss, and Brookhart receive research funding from CVS Caremark for studies on medication adherence.

We would like to thank Joy Lee for her administrative and technical help with the project.

Conflict of Interest

None disclosed.


  1. 1.
    World Health Organization. Adherence to long-term therapies: Evidence for action. Geneva, Switzerland: WHO; 2003. Available at: Accessed 1/26/09.
  2. 2.
    Benner JS, Glynn RJ, Mogun H, Neumann PJ, Weinstein MC, Avorn J. Long-term persistence in use of statin therapy in elderly patients. JAMA. 2002;288(4):455–61.PubMedCrossRefGoogle Scholar
  3. 3.
    Avorn J, Monette J, Lacour A, Bohn RL, Monane M, Mogun H, LeLorier J. Persistence of use of lipid-lowering medications: a cross-national study. JAMA. 1998;279(18):1458–62.PubMedCrossRefGoogle Scholar
  4. 4.
    Ho PM, Rumsfeld JS, Masoudi FA, et al. Effect of medication nonadherence on hospitalization and mortality among patients with diabetes mellitus. Arch Intern Med. 2006;166(17):1836–41.PubMedCrossRefGoogle Scholar
  5. 5.
    National Council on Patient Information and Education. Enhancing prescription medication adherence: a national action plan. Aug. 2007. Available at: Accessed 6/2/2008.
  6. 6.
    Mehta S, Moore RD, Graham NM. Potential factors affecting adherence with HIV therapy. AIDS. 1997;11(14):1665–70.PubMedCrossRefGoogle Scholar
  7. 7.
    Isaac LM, Tamblyn RM. Compliance and cognitive function: a methodological approach to measuring unintentional errors in medication compliance in the elderly. McGill-Calgary Drug Research Team. Gerontologist. 1993;33(6):772–81.PubMedGoogle Scholar
  8. 8.
    Tarn DM, Heritage J, Paterniti DA, Hays RD, Kravitz RL, Wenger NS. Physician communication when prescribing new medications. Arch Intern Med. 2006;166(17):1855–62.PubMedCrossRefGoogle Scholar
  9. 9.
    Svarstad BL, Bultman DC, Mount JK. Patient counseling provided in community pharmacies: effects of state regulation, pharmacist age, and busyness. J Am Pharm Assoc (Wash DC). 2004;44(1):22–9.Google Scholar
  10. 10.
    Fletcher SW, Fletcher RH, Thomas DC, et al. Patients’ understanding of prescribed drugs. J Community Health. 1979;4(3):183–9.PubMedCrossRefGoogle Scholar
  11. 11.
    Shrank WH, Avorn J. Educating patients about their medications: the limitations and potential of written drug information. Health Affairs. 2007;26(3):731–40.PubMedCrossRefGoogle Scholar
  12. 12.
    Davis TC, Wolf MS, Bass PF 3rd, Thompson JA, Tilson HH, Neuberger M, Parker RM. Literacy and misunderstanding prescription drug labels. Ann Intern Med. 2006;145(12):887–94.PubMedGoogle Scholar
  13. 13.
    Davis TC, Wolf MS, Bass PF 3rd, Middlebrooks M, Kennen E, Baker DW, Bennett CL, Durazo-Arvizu R, Bocchini A, Savory S, Parker RM. Low literacy impairs comprehension of prescription drug warning labels. J Gen Intern Med. 2006;21(8):847–51.PubMedCrossRefGoogle Scholar
  14. 14.
    Shrank WH, Agnew-Blais J, Choudhry NK, Wolf MS, Kesselheim A, Avorn J, Shekelle P. The variability and quality of medication container labels. Arch Intern Med. 2007;167(16):1760–5.PubMedCrossRefGoogle Scholar
  15. 15.
    Haynes RB, McDonald H, Garg AX. Interventions for helping patients to follow prescriptions for medications. Oxford, England: Cochrane library, Update software; 2002; issue 2.Google Scholar
  16. 16.
    Shrank W, Avorn J, Rolón C, Shekelle P. The Effect of the Content and Format of Prescription Drug Labels on Readability, Understanding and Medication Use: a Systematic Review. Annals of Pharmacotherapy. 2007;41(5):783–801.PubMedCrossRefGoogle Scholar
  17. 17.
    Bull, G. USA Today. April 28, 2005. Available at: = 34. Accessed 01/26/09
  18. 18.
    Samet JH, Libman H, Steger KA, Dhawan RK, Chen J, Shevitz AH, Dewees-Dunk R, Levenson S, Kufe D, Craven DE. Compliance with zidovudine therapy in patients infected with human immunodeficiency virus, type 1: a cross-sectional study in a municipal hospital clinic. Am J Med. 1992;92(5):495–502.PubMedCrossRefGoogle Scholar
  19. 19.
    Isaac LM, Tamblyn RM. Compliance and cognitive function: a methodological approach to measuring unintentional errors in medication compliance in the elderly. McGill-Calgary Drug Research Team. Gerontologist. 1993;33(6):772–81.PubMedGoogle Scholar
  20. 20.
    Gazmararian JA, Kripalani S, Miller MJ, Echt KV, Ren J, Rask K. Factors associated with medication refill adherence in cardiovascular-related diseases: a focus on health literacy. J Gen Intern Med. 2006;21(12):1215–21.PubMedCrossRefGoogle Scholar
  21. 21.
    Halpern MT, Khan ZM, Schmier JK, Burnier M, Caro JJ, Cramer J, Daley WL, Gurwitz J, Hollenberg NK. Recommendations for evaluating compliance and persistence with hypertension therapy using retrospective data. Hypertension. 2006;47(6):1039–48.PubMedCrossRefGoogle Scholar
  22. 22.
    Zeger SL, Liang KY. Longitudinal data analysis for discrete and continuous outcomes. Biometrics. 1986;(42):121–30.Google Scholar
  23. 23.
    DiMatteo MR. Variations in patients’ adherence to medical recommendations: a quantitative review of 50 years of research. Med Care. 2004;42(3):200–9.PubMedCrossRefGoogle Scholar
  24. 24.
    Kripalani S, Yao X, Haynes RB. Interventions to enhance medication adherence in chronic medical conditions: a systematic review. Arch Intern Med. 2007;167(6):540–50.PubMedCrossRefGoogle Scholar
  25. 25.
    Shrank WH, Asch SM, Adams J, Setodji C, Kerr EA, Keesey J, Malik S, McGlynn EA. The Quality of Pharmacologic Care for Adults in the United States. Medical Care. 2006;44(10):936–45.PubMedCrossRefGoogle Scholar
  26. 26.
    Higashi T, Shekelle PG, Solomon DH, Knight EL, Roth C, Chang JT, Kamberg CJ, MacLean CH, Young RT, Adams J, Reuben DB, Avorn J, Wenger NS. The quality of pharmacologic care for vulnerable older patients. Ann Intern Med. 2004;140(9):714–20.PubMedGoogle Scholar
  27. 27.
    Choudhry NK, Anderson G, Laupacis A, Ross-Degnan D, Normand SL, Soumerai SB. The impact of adverse events on warfarin prescribing in atrial fibrillation: a matched-pair analysis. BMJ. 2006;332:141–5.PubMedCrossRefGoogle Scholar
  28. 28.
    Steiner JF, Prochazka AV. The assessment of refill compliance using pharmacy records: methods, validity, and applications. J Clin Epidemiol. 1997;50(1):105–16.PubMedCrossRefGoogle Scholar

Copyright information

© Society of General Internal Medicine 2009

Authors and Affiliations

  • William H. Shrank
    • 1
    Email author
  • Patrick P. Gleason
    • 2
  • Claire Canning
    • 1
  • Carol Walters
    • 2
  • Alan H. Heaton
    • 3
  • Saira Jan
    • 4
  • Amanda Patrick
    • 1
  • M. Alan Brookhart
    • 1
  • Sebastian Schneeweiss
    • 1
  • Daniel H. Solomon
    • 1
  • Jerry Avorn
    • 1
  • Niteesh K. Choudhry
    • 1
  1. 1.Department of Medicine, Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women’s HospitalHarvard Medical SchoolBostonUSA
  2. 2.Prime TherapeuticsEaganUSA
  3. 3.Blue Cross Blue Shield of MinnesotaMinnesotaUSA
  4. 4.Horizon Blue Cross Blue Shield of New JerseyMinnesotaUSA

Personalised recommendations