Date of Award

Fall 2013

Degree Type


Degree Name

Doctor of Philosophy (PhD)


Pharmacy Practice

First Advisor

Joseph Thomas III

Committee Chair

Joseph Thomas III

Committee Member 1

Kenneth F. Ferraro

Committee Member 2

Bruce A. Craig

Committee Member 3

Sharon A. DeVaney


Ward, Lori Marquinne. Ph.D., Purdue University, December, 2013. Patient Perceptions of Physicians and Medication Adherence Among Medicare Part D Beneficiaries. Major Professor: Joseph Thomas III.

An observational database analysis using Medicare Current Beneficiary Survey data was conducted to examine patient perceptions of physicians and associations with adherence to antihypertensive medication among Medicare beneficiaries enrolled in Medicare Part D. The study sample included beneficiaries if they were 65 years or older, dwelling in the community, had a diagnosis of hypertension in 2007, were enrolled in Medicare Part D all 12 months in 2008, and had Medicare Part D claims for antihypertensive medication in 2008. Beneficiaries were excluded if their Medicare eligibility was due to end-stage renal disease or disability, if they resided in a long term care facility, if they had a proxy responder, or if they had a diagnosis of Alzheimer's disease or dementia. Among 2,510 beneficiaries that passed inclusion and exclusion criteria, 44 percent were in their seventies, 65 percent were female, and 83 percent were White. An overall patient perceptions of physicians scale was created using MCBS items. The overall patient perceptions of physicians had good reliability, Cronbach's alpha=0.92. Factor analysis was used to determine if there were any subscales within the patient perception of physician scale, and yielded two factors: perceived physician knowledge about the patient (Factor 1) and perceived concern (Factor 2). Medication adherence was assessed using proportion of days covered (PDC) for antihypertensive medications. Beneficiaries with a PDC of 0.80 or greater were considered to be adherent, and beneficiaries with a PDC less than 0.80 were considered to be nonadherent. Thirty-five percent of the beneficiaries were not adherent to their antihypertensive medications. Association between patient perceptions of physicians and medication adherence was assessed using stepwise multiple logistic regression that adjusted for risk factors including age, gender, race, education, income, private insurance, Medicaid, reaching the Medicare Part D prescription coverage gap, perceived health status, number of unique medications, number of doctor visits, Charlson Comorbidity Index, and clinical conditions (heart disease, heart failure, diabetes, stroke, non-skin cancers, rheumatoid arthritis, depression, Parkinson's disease, osteoporosis, and respiratory conditions). Beneficiaries with patient perceptions of physician scale scores of 37 or higher were more likely to be adherent to antihypertensive medications in comparison to beneficiaries with scores less than 37 (Odds ratio=1.341, 95% CI=1.101-1.632, p-value=0.0035). These findings indicate that patient perceptions of their physician have an impact on the patient to adhere to medication therapy.