title: Measuring adherence to antiretroviral treatment in resource-poor settings: the clinical validity of key indicators.
abstract: BACKGROUND
  Access to antiretroviral therapy has dramatically expanded in Africa in recent years, but there are no validated approaches to measure treatment adherence in these settings.
  
  
  METHODS
  In 16 health facilities, we observed a retrospective cohort of patients initiating antiretroviral therapy. We constructed eight indicators of adherence and visit attendance during the first 18 months of treatment from data in clinic and pharmacy records and attendance logs. We measured the correlation among these measures and assessed how well each predicted changes in weight and CD4 count.
  
  
  RESULTS
  We followed 488 patients; 63.5% had 100% coverage of medicines during follow-up; 2.7% experienced a 30-day gap in treatment; 72.6% self-reported perfect adherence in all clinic visits; and 19.9% missed multiple clinic visits. After six months of treatment, mean weight gain was 3.9 kg and mean increase in CD4 count was 138.1 cells/mm3.Dispensing-based adherence, self-reported adherence, and consistent visit attendance were highly correlated. The first two types of adherence measure predicted gains in weight and CD4 count; consistent visit attendance was associated only with weight gain.
  
  
  CONCLUSIONS
  This study demonstrates that routine data in African health facilities can be used to monitor antiretroviral adherence at the patient and system level.
authors.affiliation: Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston MA, USA. Dennis_Ross-Degnan@hms.harvard.edu
authors.forename: Dennis
authors.initials: D
authors.lastname: Ross-Degnan
authors.forename: Marsha
authors.initials: M
authors.lastname: Pierre-Jacques
authors.forename: Fang
authors.initials: F
authors.lastname: Zhang
authors.forename: Hailu
authors.initials: H
authors.lastname: Tadeg
authors.forename: Lillian
authors.initials: L
authors.lastname: Gitau
authors.forename: Joseph
authors.initials: J
authors.lastname: Ntaganira
authors.forename: Robert
authors.initials: R
authors.lastname: Balikuddembe
authors.forename: John
authors.initials: J
authors.lastname: Chalker
authors.forename: Anita K
authors.initials: AK
authors.lastname: Wagner
mesh_terms: D000328:Adult; D000351:Africa, Eastern; D044966:Anti-Retroviral Agents / Q000009:adverse effects / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006268:Health Facilities; D006801:Humans; D008297:Male; D010349:Patient Compliance / Q000706:statistics & numerical data*; D010865:Pilot Projects; D012189:Retrospective Studies; D015430:Weight Gain
chemical_list: D044966:Anti-Retroviral Agents