Abstract
Purpose: :
To determine if the Glaucoma Treatment Compliance Assessment tool (GTCAT), a survey based on the Health Belief Model (HBM), is associated with objective and subjective measures of compliance in glaucoma patients.
Methods: :
Fifty-eight patients from a tertiary glaucoma practice participated in this cross-sectional survey. All patients were using travoprost and the Travatan Dosing Aid. We used a subjective measure: S1- the number of days missed in the last month, and three objective measures of compliance (O1-the proportion of days that the patient administered the drop within 3 hours of the designated time and used the appropriate number of drops; O2- the proportion of days that the patient administered the drop within 3 hours of the designated time; and O3- the proportion of days that the patient administered the drop within 6 hours of the designated time). We used parametric and nonparametric models to identify significant associations between compliance and survey questions.
Results: :
Patients reported a mean 1.79 +/- 2.6 (range 0-14) days without using medication with a S1 measure of 94%. The proportion of days compliant by measures O1, O2, and O3 were 70%, 80%, 86%, respectively. Age, ethnicity, and the HBM constructs of knowledge, susceptibility, benefits, and barriers were significantly associated with one or more of the compliance measures (p<0.05).
Conclusions: :
Patients overestimated compliance in comparison to objective measures. The survey has predictive validity with objective and subjective measures of compliance. We need further studies before recommending clinical use of the GTCAT.
Keywords: clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology • clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials