Development and Initial Evaluation of the Psychometric Properties of Self-Efficacy and Adherence Scales for Patients with a Left Ventricular Assist Device

Abstract

Context—

No tools exist to measure patients' self-efficacy for and adherence to the complex home-care regimen after having a left ventricular device (LVAD) implanted.

Objective—

To develop 2 new instruments, the LVAD Patient Self-Efficacy Scale (LPSES) and the LVAD Patient Home Management Adherence Scale (LPHMAS), and evaluate their psychometric properties.

Methods—

This multistage instrumentation study recruited 102 patients (77.5% men and 22.5% women) aged 20 to 82 years, predominantly from the Midwest (34.3%) and the Northeast (26.5%) regions of the United States. Main indications for LVAD were bridge-to-transplant (69.6%) and destination therapy (21.6%), with mean implant duration of 19.9 (SD, 15.5) months. Study participants completed the following instruments: LPSES, LPHMAS, General Self-Efficacy Scale (GSES), Medical Outcomes Study General Adherence (MOSGA), and Self-Care Heart Failure Index (SCHFI) confidence and maintenance subscales. Item analyses, psychometric properties including factorial and convergent validities, and internal consistency reliability were tested.

Results—

Factor analyses showed that the variances for the 20-item LPSES and 9-item LPHMAS were 60.2% and 53.6%, respectively. Convergent validity of the newly developed instruments was supported by the following correlations: LPSES and GSES (r = 0.34); LPSES and SCHFI-confidence (r = 0.60); LPHMAS and MOSGA (r = 0.33); LPHMAS and SCHFI-maintenance (r = 0.40). Internal consistency reliability coefficients were 0.94 (LPSES) and 0.84 (LPHMAS). Based on these data, the LPSES and LPHMAS are valid and reliable measures of self-efficacy and adherence specific for LVAD patients. Confirmatory testing is needed to further support the validity of these instruments for use in research and clinical practice.

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References

Zulkosky

. Self-efficacy: a concept analysis. Nurs Forum. 2009;44(2):93–102. doi:10.1111/j.1744-6198.2009.00132.x.

Jones

Razi

. Self-efficacy and self-management after stroke: a systematic review. Disabil Rehabil. 2011;33(10):797–810. doi:10.3109/09638288.2010.511415.

Berben

Dobbels

Engberg

Hill

De Geest

. An ecological perspective on medication adherence. West J Nurs Res. 2012;34(5):635–653. doi:10.1177/0193945911434518.

Wouters

Bouvy

Van Geffen

Gardarsdottir

Stiggelbout

Van Dijk

. Antidepressants in primary care: patients' experiences, perceptions, self-efficacy beliefs, and nonadherence. Patient Prefer Adherence. 2014;8:179–190. doi:10.2147/PPA.S53748.

World Health Organization. Setting the scene: Chapter 1 defining adherence. 2003:17–19. http://www.who.int/chp/knowledge/publications/adherence_Section1.pdf. Accessed October 6, 2014.

Casida

Peters

Magnan

. Self-care demands of persons living with an implantable left-ventricular assist device. Res Theory Nurs Pract. 2009;23(4):279–293.

Widmar

Dietrich

Minnick

. How self-care education in ventricular assist device programs is organized and provided: a national study. Heart Lung. 2014;43(1):25–31. doi:10.1016/j.hrtlng.2013.09.003.

Casida

Ilaqua

. A survey of nurses in the mechanical circulatory support programs in the United States. Heart Lung. 2011;40(4):e103–e111. doi:10.1016/j.hrtlng.2010.12.001.

Feldman

Pamboukian

Teuteberg

. The 2013 International Society for Heart and Lung Transplantation Guidelines for mechanical circulatory support: executive summary. J Heart Lung Transplant. 2013;32(2):157–187. doi:10.1016/j.healun.2012.09.013.

10.

Luszczynska

Scholz

Schwarzer

. The general self-efficacy scale: multicultural validation studies. J Psychol. 2005;139(5):439–457.

11.

Hays

. The medical outcomes study (MOS) measures of patient adherence. http://www.rand.org/content/dam/rand/www/external/health/surveys_tools/mos/mos_adherence_survey.pdf. Accessed October 6, 2014.

12.

Raebel

Schmittdiel

Karter

Konieczny

Steiner

. Standardizing terminology and definitions of medication adherence and persistence in research employing electronic databases. Med Care. 2013;51(8 suppl 3):S11–S21. doi:10.1097/MLR.0b013e31829b1d2a.

13.

Thoratec Corporation. Heart Mate II Left Ventricular Assist System. Patient Handbook. Pleasanton, CA: Thoratec Corporation; 2012.

14.

HeartWare, Inc. HeartWare Ventricular Assist System. Instruction for Use. Miami Lakes, FL: HeartWare, Inc; 2012.

15.

Casida

Marcuccilli

Peters

Wright

. Lifestyle adjustments of adults with long-term implantable left ventricular assist devices: a phenomenologic inquiry. Heart Lung. 2011;40(6):511–520. doi:10.1016/j.hrtlng.2011.05.002.

16.

Sandau

Hoglund

Weaver

Boisjolie

Feldman

. A conceptual definition of quality of life with a left ventricular assist device: results from a qualitative study. Heart Lung. 2014;43(1):32–40. doi:10.1016/j.hrtlng.2013.09.004.

17.

Lynn

. Determination and quantification of content validity. Nurs Res. 1986;35(6):382–385.

18.

Readability Formulas. SMOG readability formula. http://www.readabilityforumulas.com/smog-readability-formula.php. Accessed October 6, 2014.

19.

Jobe

Mingay

. Cognitive research improves questionnaires. Am J Public Health. 1989;79(8):1053–1055.

20.

Schwarzer

Jerusalem

. Generalized self-efficacy scale. In: Weinman

Wright

Johnston

, eds. Measures in Health Psychology: A User's Portfolio. Causal and Control Beliefs. Windsor, United Kingdom: Nfer-Nelson; 1995:35–37.

21.

Vellone

Riegel

Cocchieri

. Psychometric testing of the Self-Care of Heart Failure Index Version 6.2. Res Nurs Health. 2013;36(5):500–511. doi:10.1002/nur.21554.

22.

Reigel

. SCHFI V 6.2 self-care heart failure index. http://www.self-careofheartfailureindex.com. Accessed October 6, 2014.

23.

Pett

Lacey

Sullivan

. Making Sense of Factor Analysis. Thousand Oaks, CA: Sage; 2003.

24.

DeVellis

. Scale Development: Theory and Applications. Los Angeles, CA: Sage; 2012.

25.

Nunnally

Bernstein

. Psychometric Theory. McGraw Hill Series in Psychology. New York, NY: McGrawHill; 1994.

26.

Frank-Stromborg

Olsen

. Instruments for Clinical Health-Care Research. Sudbury, MA: Jones and Bartlett; 1997.

27.

Waltz

Strickland

Lenz

. Measurement in Nursing and Health Research. New York, NY: Springer; 2010.

28.

Van Selm

Jankowski

. Conducting on-line surveys. Qual Quant. 2006;40:435–456.

29.

Interagency Registry for Mechanically Assisted Circulatory Support. ITERMACS statistical summaries. https://www.uab.edu/medicine/intermacs/research/statistical-summaries. Accessed October 6, 2014.