A Comparison of Adherence Assessment Methods Utilized in the United States: Perspectives of Researchers, HIV-Infected Children, and their Caregivers

Abstract

This study sought to elucidate methodological issues in adherence research by comparing multiple methods of assessing adherence to antiretroviral medication. From 2003 to 2004, 24 youths with vertically infected HIV disease (mean age = 14.0 years; range, 8-18) and their caregivers participated in a 6-month study. These children were all on highly active antiretroviral therapy (HAART) and were relatively healthy (mean CD4 absolute count = 711.8 +/- 604.5). Adherence was assessed with the Medication Event Monitoring System (MEMS), pill counts, and interviews. Patients and caregivers completed the Perceptions of Adherence Study Participation (PASP) questionnaire. MEMS provided the most detailed adherence information, and good reliability was indicated by significant correlations with medical markers. Pill counts provided similar adherence rates, while patients and caregivers reported nearly perfect adherence in interviews. Problems were experienced with each method: MEMS were expensive, had cap malfunctions, and lack a consistent guiding principle for data interpretation. With pill counts, families forgot to bring all medication bottles to clinic, and interviews were compromised by social desirability and difficulty reaching families by telephone. Most patients and caregivers believed study participation improved the child's adherence, although PASP ratings were unrelated to adherence at the study endpoint. While MEMS may be most reliable, pill counts offer comparable data and are less costly, while interviews seemed least accurate in this study. Most participants reported positive perceptions of their research experience. A consensus among researchers is needed for defining and measuring adherence, and specific recommendations are offered for achieving this goal.

Comparison of Adherence Monitoring Tools and Correlation to Virologic Failure in a Pediatric HIV Clinical Trial

“…21 Adherence by pill count reveals lower adherence estimates than self-reports, 18 and offers comparable adherence data to Medication Event Monitoring System caps (MEMS cap) while being less costly. 22 In our study, poor adherence by announced pill count was also significantly associated with VF. The child self-report of any missed doses since the last visit had a similar level of significance compared to adherence by pill count (Table 3) but was much faster to administer.…”

Assessment of HIV antiretroviral therapy adherence by measuring drug concentrations in hair among children in rural Uganda

“…Self-report of adherence typically overestimates adherence (Bhattacharya & Dubey, 2011; Biressaw, Abegaz, Abebe, Taye, & Belay, 2013; Martin et al, 2009; Naar-King, Frey, Harris, & Arfken, 2005), as it may be influenced by social desirability and recall biases (Kagee & Nel, 2012). Clinic-based pill counts may be inaccurate if children or caregivers remove extra medication to appear more adherent (Simoni et al, 2006).…”

Physician Estimate of Antiretroviral Adherence in India: Poor Correlation with Patient Self-Report and Viral Load

“…Bisson et al 16 have found pharmacy claim adherence data predicted virologic failure better than CD4 monitoring. Martin et al 17 compared a medication event monitoring system (MEMS), pill counts, and self-reported adherence among U.S. youth and their caregivers. MEMS provided the most reliable measure of adherence, but the authors suggested pill counts might be used where cost of MEMS is prohibitive.…”