Journal of General Internal Medicine

, Volume 17, Issue 1, pp 1–11 | Cite as

How well do clinicians estimate patients’ adherence to combination antiretroviral therapy?

  • Loren G. Miller
  • Honghu Liu
  • Ron D. Hays
  • Carol E. Golin
  • C. Keith Beck
  • Steven M. Asch
  • Yingying Ma
  • Andrew H. Kaplan
  • Neil S. Wenger
Original Articles


OBJECTIVE: Adherence to combination antiretroviral therapy is critical for clinical and virologic success in HIV-infected patients. To combat poor adherence, clinicians must identify nonadherent patients so they can implement interventions. However, little is known about the accuracy of these assessments. We sought to describe the accuracy of clinicians’ estimates of patients’ adherence to combination antiretroviral therapy.

SETTING: Public HIV clinic.

DESIGN: Prospective cohort study. During visits, we asked clinicians (nurse practitioners, residents and fellow, and their supervising attending physicians) to estimate the percentage of antiretroviral medication taken by patients over the last 4 weeks and predicted adherence over the next 4 weeks. Adherence was measured using electronic monitoring devices, pill counts, and self-reports, which were combined into a composite adherence measure.

PATIENTS AND PARTICIPANTS: Clinicians estimated 464 episodes of adherence in 82 patients.

RESULTS: Among the 464 adherence estimates, 264 (57%) were made by principal care providers (31% by nurse practitioners, 15% by fellows, 6% by residents, and 5% by staff physicians) and 200 (43%) by supervising attending physicians. Clinicians’ overestimated measured adherence by 8.9% on average (86.2% vs 77.3%). Greater clinician inaccuracy in adherence prediction was independently associated with higher CD4 count nadir (1.8% greater inaccuracy for every 100 CD4 cells, P=.005), younger patient age (3.7% greater inaccuracy for each decade of age, P=.02), and visit number (P=.02). Sensitivity of detecting nonadherent patients was poor (24% to 62%, depending on nonadherence cutoff). The positive predictive value of identifying a patient as nonadherent was 76% to 83%.

CONCLUSIONS: Clinicians tend to overestimate medication adherence, inadequately detect poor adherence, and may therefore miss important opportunities to intervene to improve antiretroviral adherence.

Key words

adherence compliance HIV clinician assessment antiretroviral therapy 


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Copyright information

© Blackwell Science Inc 2002

Authors and Affiliations

  • Loren G. Miller
    • 1
    • 5
  • Honghu Liu
    • 3
    • 5
  • Ron D. Hays
    • 3
    • 5
  • Carol E. Golin
    • 6
  • C. Keith Beck
    • 2
  • Steven M. Asch
    • 3
    • 4
  • Yingying Ma
    • 3
  • Andrew H. Kaplan
    • 7
  • Neil S. Wenger
    • 3
    • 5
  1. 1.Division of Infectious DiseasesHarbor-UCLA Medical Center and Harbor-UCLA Research and Education InstituteTorrance
  2. 2.Division of Allergy and ImmunologyHarbor-UCLA Medical CenterTorrance
  3. 3.the Department of MedicineUniversity of CaliforniaLos Angeles
  4. 4.the Department of MedicineVA Greater Los Angeles Healthcare SystemLos Angeles
  5. 5.the UCLA AIDS InstituteLos Angeles
  6. 6.Department of MedicineUniversity of North CarolinaChapel Hill
  7. 7.Division of Infectious DiseasesUniversity of North CarolinaChapel Hill

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