title: How well do clinicians estimate patients' adherence to combination antiretroviral therapy?
abstract: 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.
  
  
  METHODS
  Public HIV clinic.
  
  
  METHODS
  Prospective cohort study. During visits, we asked clinicians (nurse practitioners, residents and fellows, 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.
  
  
  METHODS
  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.
authors.affiliation: Division of Infectious Diseases, Harbor-UCLA Medical Center, Torrance Calif., 90509 USA. lgmiller@ucla.edu
authors.forename: Loren G
authors.initials: LG
authors.lastname: Miller
authors.forename: Honghu
authors.initials: H
authors.lastname: Liu
authors.forename: Ron D
authors.initials: RD
authors.lastname: Hays
authors.forename: Carol E
authors.initials: CE
authors.lastname: Golin
authors.forename: C Keith
authors.initials: CK
authors.lastname: Beck
authors.forename: Steven M
authors.initials: SM
authors.lastname: Asch
authors.forename: Yingying
authors.initials: Y
authors.lastname: Ma
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Kaplan
authors.forename: Neil S
authors.initials: NS
authors.lastname: Wenger
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D023241:Antiretroviral Therapy, Highly Active; D001291:Attitude of Health Personnel; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000523:psychology*; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D010358:Patient Participation; D011369:Professional-Patient Relations; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D019380:Anti-HIV Agents