Assessment of Outpatients' Knowledge and Adherence on Warfarin: The Impact of a Simple Educational Pamphlet

Document Type : Research article


1 Rajaei Cardiovascular, Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran.

2 Department of Clinical Pharmacy, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

3 Chronic Respiratory Diseases Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.

4 Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.


Warfarin is a critical medication that is broadly used for the treatment and prevention of
thromboembolic disorders. Due to warfarin’s narrow therapeutic index, it is crucial that patients
follow an appropriate dosage regimen. Patient knowledge is one of the most important factors
to safe and effective use of warfarin. Due to the obvious risks of anticoagulants administration,
evaluating patients’ awareness seems to be crucial. The purpose of this article was to evaluate
the effects of intervention by an informative pamphlet on knowledge and adherence of patients
who consumed warfarin. Two-hundred and fifty patients receiving warfarin were assigned to
the study. They were asked to fill in the questionnaire. Then patients were provided with an
educational pamphlet. In the second interview, patients filled the questionnaire again. Obtained
data were assessed and analyzed by Excel software and SPSS version 18.0. Out of 250 patients
who entered the study, 150 patients attended for the second interview. Data analysis revealed
that out of 13 explanatory factors, only patients’ literacy level and income were the predictors
which inversely correlated with the patients’ adherence (r = -0.44; p = 0.00040). Our educational
intervention had a positive impact on patients’ knowledge regarding anticoagulation (p < 0.0001).
Our findings revealed that a written informative pamphlet could effectively increase patients’
anticoagulation knowledge. Since, poorly literate patients had a lesser level of knowledge
before and after educational intervention, it is recommended to develop appropriate educational
programs especially designed for this group of patients.


Main Subjects

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