Validation of a New Three-Item Self-Report Measure for Medication Adherence.
Few self-report measures of medication adherence have been rigorously developed and validated against electronic drug monitoring (EDM). Assess the validity of the 3-item self-report scale by comparing it with a contemporaneous EDM measure. We conducted an observational study in which adherence assessments were done monthly for up to 4 months for 81 patients with HIV who were taking antiretroviral medications. We report results for both HIV antiretroviral medications, and also for other, non-HIV-related medications. Raw and calibrated self-report adherence measures, electronic drug monitoring adherence measures, and sociodemographic variables. The mean age of patients was 46 years, 37 % were female, 49 % had some education beyond high school, 22 % were Black, and 22 % were Hispanic. Cronbach's alphas for the 3-item scale for HIV and non-HIV medications were 0.83 and 0.87, respectively. The mean differences (raw/uncalibrated self-report scale minus EDM) for HIV and non-HIV medications were 7.5 and 5.2 points on a 100-point scale (p < 0.05 for both). Pearson correlation coefficients between the calibrated 3-item scale and the EDM for HIV and non-HIV medications were 0.47 and 0.59, respectively. The c-statistics for the ROC curves for the calibrated scale, using cut-offs of 0.8 and 0.9 for the EDM gold standard measure to define non-adherence, were between 0.74 and 0.76 for HIV and non-HIV medications. This 3-item adherence self-report scale showed good psychometric characteristics and good construct validity when compared with an EDM standard, for both HIV and non-HIV medications. In clinical care it can be a useful first-stage screener for non-adherence. In clinical research and quality improvement settings it can be a useful tool when more complex and expensive methods such as EDM or pharmacy claims are impractical or unavailable.
Department of Health Services, Policy & Practice, Brown University School of Public Health, Box G-121-7, 121 South Main St., Providence, RI, 02912, USA. ira_wilson@brown.edu.
Ira B
IB
Wilson
Department of Health Services, Policy & Practice, Brown University School of Public Health, Box G-121-7, 121 South Main St., Providence, RI, 02912, USA.
Yoojin
Y
Lee
Department of Health Services, Policy & Practice, Brown University School of Public Health, Box G-121-7, 121 South Main St., Providence, RI, 02912, USA.
Joanne
J
Michaud
Center for Survey Research, University of Massachusetts, Boston, MA, USA.
Floyd J
FJ
Fowler
Center for Health Solutions, Tufts Medical Center, Boston, MA, USA.
William H
WH
Rogers
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000379:methods*; D004359:Drug Therapy, Combination; D057286:Electronic Health Records; D005260:Female; D015658:HIV Infections / Q000188:drug therapy; D006801:Humans; D008297:Male; D055118:Medication Adherence / Q000523:psychology*; D008875:Middle Aged; D011594:Psychometrics / Q000379:methods; D057566:Self Report; D011795:Surveys and Questionnaires
D019380:Anti-HIV Agents
HIV; Highly active antiretroviral therapy; Medication adherence; Patient compliance; Self-report