Abstract
Medication adherence studies increasingly collect data electronically, often using Medication Event Monitoring System (MEMS) caps. Analyses typically focus on summary adherence measures, although more complete analyses are possible using adaptive statistical methods. These methods were used to describe individual-subject adherence patterns for MEMS data from a clinical trial. Subjects were adaptively clustered into groups with similar adherence patterns and clusters were compared on a variety of subject characteristics. There were seven different adherence clusters: consistently high, consistently moderately high, consistently moderate, consistently moderately low, consistently low, deteriorating starting early, and deteriorating late. Compared to other subjects, subjects with consistently high and consistently moderately high adherence were more likely to be male, White, and older and to maintain during study participation a CD4 cell count over 500 and an HIV viral load of at most 400 copies/ml. These results demonstrate the effectiveness of adaptive methods for comprehensive analysis of MEMS data.
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Acknowledgments
This work was supported in part by grant R01 AI57043 from the NIAID of the NIH, Oregon Health & Science University’s Oregon Clinical and Translational Research Institute (OCTRI) through grant UL1 RR024140 from the NCRR of the NIH and the NIH Roadmap for Medical Research, Yale University’s Center for Interdisciplinary Research on AIDS (CIRA) through grant P30 MH62294 from the NIMH of the NIH. Collection of the data used in analyses was supported in part by grant R01 NR04744 from the NINR of the NIH, Yale University’s GCRC Program through grant M01 RR00125 from the NCRR of the NIH, and the University of Connecticut Health Center’s GCRC Program through grant M01 RR06192 from the NCRR of the NIH. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIAID, the NCRR, the NIMH, the NINR, or the NIH.
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Knafl, G.J., Bova, C.A., Fennie, K.P. et al. An Analysis of Electronically Monitored Adherence to Antiretroviral Medications. AIDS Behav 14, 755–768 (2010). https://doi.org/10.1007/s10461-008-9512-z
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DOI: https://doi.org/10.1007/s10461-008-9512-z