Pharmacy World & Science

, Volume 31, Issue 4, pp 426–431 | Cite as

The A14-scale: development and evaluation of a questionnaire for assessment of adherence and individual barriers

  • Susanne Jank
  • Thilo Bertsche
  • Dieter Schellberg
  • Wolfgang Herzog
  • Walter E. HaefeliEmail author
Short Research Report


Objective To develop a questionnaire (“A14”) for the description of adherence and individual barriers as basis for adherence-enhancing interventions in the clinical and pharmaceutical setting, and to compare it to the validated German MMAS (Morisky Medication Adherence Scale). Method Fourteen questions with a 5-item likert-scale from “never” (4) to “very often” (0) were given to 150 medical inpatients. According to their score, patients were classified into non-adherent (score <50) or adherent (score 50–56). On the dichotomous MMAS, “yes” is scored 0 and “no” 1 point, a total score of 4 indicating adherence. Patients with complete scales were compared with the remaining patients regarding socio-demographic factors. Descriptive statistics, Cronbach’s Alpha, Spearman correlation, and κ were computed. Results Eighty-three participants completed both scales. Patients with missing values differed significantly regarding age, education, and adherence according to MMAS. Cronbach’s Alpha for A14 was 0.861. MMAS and A14 median total scores were 4 and 52, respectively. About 39.5% of patients were non-adherent as per MMAS compared to 40% as per A14; κ was 0.262 (P = 0.016). The total scores correlated with a Rho-value of 0.43 (P < 0.001). Conclusion The A14-scale showed good internal consistency and a significant correlation with the MMAS suggesting that it merits further investigation.


A14-scale Drug therapy German language Patient compliance Psychometry Questionnaire Validation 



We would like to thank all patients taking part in the study and the ward staff of “Siebeck” for logistical support. Our gratitude goes to RN Barbara Williams and Prof. Ingeborg Walter-Sack for their assistance in the forward-backward-translation of the A14-scale.


This work was in part supported by the AOK Baden-Württemberg Health Insurance Company.

Conflicts of interest



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Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  • Susanne Jank
    • 1
    • 2
  • Thilo Bertsche
    • 1
    • 2
  • Dieter Schellberg
    • 3
  • Wolfgang Herzog
    • 3
  • Walter E. Haefeli
    • 1
    Email author
  1. 1.Department of Internal Medicine VI, Clinical Pharmacology and Pharmacoepidemiology, Medizinische Klinik (Krehl-Klinik)University of HeidelbergHeidelbergGermany
  2. 2.Cooperation Unit Clinical PharmacyUniversity of HeidelbergHeidelbergGermany
  3. 3.Department of Internal Medicine II, Psychosomatic and General Internal MedicineUniversity of HeidelbergHeidelbergGermany

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