Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012 Dec;50(12):1013-9.
doi: 10.1097/MLR.0b013e318269e121.

Initial validation of a self-report measure of the extent of and reasons for medication nonadherence

Corrine I Voils  1 , Matthew L Maciejewski, Rick H Hoyle, Bryce B Reeve, Patrick Gallagher, Christopher L Bryson, William S Yancy Jr
Affiliations

Initial validation of a self-report measure of the extent of and reasons for medication nonadherence

Corrine I Voils et al. Med Care. 2012 Dec.

Abstract

Background: Self-report measures of medication nonadherence confound the extent of and reasons for medication nonadherence. Each construct is assessed with a different type of psychometric model, which dictates how to establish reliability and validity.

Objectives: To evaluate the psychometric properties of a self-report measure of medication nonadherence that assesses separately the extent of nonadherence and reasons for nonadherence.

Research design: Cross-sectional survey involving the new measure and comparison measures to establish convergent, discriminant, and predictive validity. The new measure was readministered 2-21 days later.

Subjects: A total of 202 veterans with treated hypertension were recruited from the Durham Veterans Affairs Medical Center.

Measures: A new self-report measure assessed the extent of nonadherence and reasons for nonadherence. Comparison measures included self-reported medication self-efficacy, beliefs about medications, impression management, conscientiousness, habit strength, and an existing nonadherence measure.

Results: Three items assessing the extent of nonadherence produced reliable scores for this sample, α = 0.84 (95% confidence interval, 0.80-0.87). Correlations with comparison measures provided evidence of convergent and discriminant validity. Correlations with systolic ( r = 0.27, P < 0.0001) and diastolic (r = 0.27, P < 0.0001) blood pressure provided evidence of predictive validity. Reasons for nonadherence were assessed with 21 independent items. Intraclass correlations were 0.58 for the extent score and ranged from 0.07 to 0.64 for the reasons.

Conclusions: The dual conceptualization of medication nonadherence allowed a stronger evaluation of the reliability and validity than was previously possible with measures that confounded these 2 constructs. Measurement of self-reported nonadherence consistent with psychometric principles will enable reliable, valid evaluation of interventions to reduce nonadherence.

PubMed Disclaimer

Comment in

References

    1. Horne R. Adherence to medication: A review of existing research. In: Myers LB, Midence K, editors. Adherence to Treatment in Medical Conditions. London: Harwood Academic; 1998. pp. 285–310.
    1. Sherbourne CD, Hays RD, Ordway L, et al. Antecedents of adherence to medical recommendations: results from the Medical Outcomes Study. J Behav Med. 1992;15:447–468. - PubMed
    1. McDermott MM, Schmitt B, Wallner E. Impact of medication nonadherence on coronary heart disease outcomes: A critical review. Arch Intern Med. 1997;157:1921–1929. - PubMed
    1. DiMatteo MR. Enhancing patient adherence to medical recommendations. JAMA. 1994;271:79–83. - PubMed
    1. Osterberg L, Blaschke T. Adherence to medication. N Engl J Med. 2005;353:487–497. - PubMed

Publication types