Comparison of three composite compliance indices in a trial of self-administered preventive therapy for tuberculosis in HIV-infected Ugandan adults

V. Pekovic, H. Mayanja, M. Vjecha, J. Johnson, A. Okwera, P. Nsubuga, R. Mugerwa, J. Ellner, C. Whalen

Research output: Contribution to journalArticle


Compliance with tuberculosis preventive therapy in a randomized placebo-controlled trial in 2736 HIV-infected Ugandans was measured using urinary isoniazid metabolite testing, clinic attendance, and self-report. Overall, 77% of urine tests were positive, subjects kept 85% of their scheduled visits while on therapy, and 69% reportedly never forgot to take their medication. Different strategies were used for constructing three composite compliance indices in active arms: (1) an unweighted index of the summed scores on scaled compliance measures; (2) a weighted index using weights obtained from a survey of experts on tuberculosis; and (3) a statistically weighted index using principal components analysis. Composite indices were evaluated for reliability, validity, and practical utility. Understanding of the regimen, study arm, subsequent follow-up, tuberculosis status, and urine spot-check result were associated with composite compliance scores. The unweighted index in this study performed as well as the weighted indices.

Original languageEnglish (US)
Pages (from-to)597-607
Number of pages11
JournalJournal of Clinical Epidemiology
Issue number7
Publication statusPublished - Jul 1998
Externally publishedYes



  • Compliance
  • HIV infection
  • Isoniazid
  • Preventive therapy
  • Tuberculosis

ASJC Scopus subject areas

  • Medicine(all)
  • Public Health, Environmental and Occupational Health
  • Epidemiology

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