Talk to the Veterans Crisis Line now
U.S. flag
An official website of the United States government

VA Health Systems Research

Go to the VA ORD website
Go to the QUERI website

HSR&D Citation Abstract

Search | Search by Center | Search by Source | Keywords in Title

Accuracy of Patient-reported Adherence to Glaucoma Medications on a Visual Analog Scale Compared With Electronic Monitors.

Sayner R, Carpenter DM, Blalock SJ, Robin AL, Muir KW, Hartnett ME, Giangiacomo AL, Tudor G, Sleath B. Accuracy of Patient-reported Adherence to Glaucoma Medications on a Visual Analog Scale Compared With Electronic Monitors. Clinical therapeutics. 2015 Sep 1; 37(9):1975-85.

Related HSR&D Project(s)

Dimensions for VA is a web-based tool available to VA staff that enables detailed searches of published research and research projects.

If you have VA-Intranet access, click here for more information

VA staff not currently on the VA network can access Dimensions by registering for an account using their VA email address.
   Search Dimensions for VA for this citation
* Don't have VA-internal network access or a VA email address? Try searching the free-to-the-public version of Dimensions


PURPOSE: Glaucoma medications can improve clinical outcomes when patients adhere to their medication regimen. Providers often ask patients with glaucoma to self-report their adherence, but the accuracy of self-reporting has received little scientific attention. The purpose of this article was to compare a self-reported medication adherence measure with adherence data collected from Medication Event Monitoring Systems (MEMS) electronic monitors. An additional goal was to identify which patient characteristics were associated with overreporting adherence on the self-reported measure. METHODS: English-speaking adult patients with glaucoma were recruited from 6 ophthalmology practices for this observational cohort study. Patients were interviewed after their initial visit and were given MEMS contains, which recorded adherence over a 60-day period. MEMS percent adherence measured the percentage of the prescribed number of doses taken. MEMS-measured timing adherence assessed the percent doses taken on time. Patients self-reported adherence to their glaucoma medications on a visual analog scale (VAS) ~60 days after the baseline visit. Bivariate analyses and logistic regressions were used to analyze the data. Self-reported medication adherence on the VAS was plotted against MEMS adherence to illustrate the discrepancy between self-reported and electronically monitored adherence. FINDINGS: The analyses included 240 patients who returned their MEMS containers and self-reported medication adherence at the 60-day follow-up visit. Compared with MEMS-measured percent adherence, 31% of patients (n = 75) overestimated their adherence on the VAS. Compared with MEMS-measured timing adherence, 74% (n = 177) of patients overestimated their adherence. For the MEMS-measured percent adherence, logistic regression revealed that patients who were newly prescribed glaucoma medications were significantly more likely to overreport adherence on the VAS (odds ratio, 3.07 [95% CI, 1.22-7.75]). For the MEMS-measured timing adherence, being male (?(2) test, 6.78; P = 0.009) and being prescribed glaucoma medications dosed multiple times daily (?(2) test, 4.02; P = 0.045) were significantly associated with patients overreporting adherence. However, only male sex remained a significant predictor of overreporting adherence in the logistic regression (odds ratio, 4.05 [95% CI, 1.73-9.47]). IMPLICATIONS: Many patients with glaucoma, especially those newly diagnosed, overestimated their medication adherence. Because patients were likely to overreport the percent doses taken and timing adherence, providers may want to ask patients additional questions about when they take their glaucoma medications to potentially detect issues with taking these medications on time.

Questions about the HSR website? Email the Web Team

Any health information on this website is strictly for informational purposes and is not intended as medical advice. It should not be used to diagnose or treat any condition.