International Journal of Clinical Pharmacy

, Volume 38, Issue 4, pp 816–821 | Cite as

Adherence in outpatients taking warfarin and its effect on anticoagulation control in Jordan

  • Mera A. AbabnehEmail author
  • Sayer I. Al-Azzam
  • Karem H. Alzoubi
  • Abeer M. Rababa’h
Research Article


Background Medication adherence is an important element for the success of any therapeutic plan. The picture is more complicated with warfarin, due to its small therapeutic window and patients’ needs to have effective anticoagulation control. Objective To measure warfarin-adherence, warfarin-knowledge and to assess the relationship between adherence and anticoagulation control. Setting Adult outpatients (≥18 years) taking warfarin at two medical sites in north of Jordan were invited to participate. Method This was a cross sectional study in which survey questionnaire that included demographic, clinical, warfarin related questions and Morisky Medication Adherence Scale (MMAS-8) was administered to patients in Arabic language. International normalization ratio (INR) readings were retrieved from patients’ medical records. Main outcome measure MMAS-8 adherence scores and time within therapeutic range were calculated. Results More than half of study participants (54 %) were adherent (MMAS-8 = 8). The MMAS-8 adherence scores were significantly associated with warfarin-knowledge scores (Spearman’s ρ = 0.291, p = 0.000). Adherent patients were more likely to have good anticoagulation control compared to non-adherent patients (MMAS-8 ≤ 7). Conclusion Adherence to warfarin therapy can have a substantial effect on anticoagulation control. Thus, healthcare practitioners should consider strategies to improve patient adherence to warfarin.


Adherence Anticoagulation control Jordan Knowledge MMAS-8 Warfarin 



We would like to acknowledge Professor Donald E. Morisky for providing us with the 8-item Morisky Medication Adherence Scale.


This study was supported by the Ministry of Higher Education and Scientific Research, Amman, Jordan (Grant number 104/2012).

Conflicts of interest

There is no conflict of interest.


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Copyright information

© Springer International Publishing 2016

Authors and Affiliations

  • Mera A. Ababneh
    • 1
    Email author
  • Sayer I. Al-Azzam
    • 1
  • Karem H. Alzoubi
    • 1
  • Abeer M. Rababa’h
    • 1
  1. 1.Department of Clinical Pharmacy, Faculty of PharmacyJordan University of Science and TechnologyIrbidJordan

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