Back to Journals » Patient Preference and Adherence » Volume 3

Development and validation of a scale to measure patients’ trust in pharmacists in Singapore

Authors Zhang X, Jin J, Ngorsuraches S, Li S

Published 24 November 2008 Volume 2009:3 Pages 1—7


Review by Single-blind

Peer reviewer comments 3

Xu-Hao Zhang1, Jing Jin1, Surachat Ngorsuraches2, Shu-Chuen Li3

1Department of Pharmacy, National University of Singapore, Republic of Singapore; 2Department of Pharmacy Administration, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Thailand; 3Discipline of Pharmacy and Experimental Pharmacology, School of Biomedical Sciences, University of Newcastle, Newcastle, Australia

Objective: To develop and validate a scale to measure patients’ trust in pharmacists for use as an outcomes predictor in pharmacoeconomic and pharmaceutical care studies.

Methods: Literature review, study team discussion and focus group discussions were conducted to generate items of a candidate version to be pilot-tested for content validity. An amended candidate version was then tested among eligible Singaporeans across different ethnic and age groups. Score distributions were assessed for discriminatory power and item analyses for finalizing items. Exploratory factor analysis was used to identify dimensionality and homogeneous items. Cronbach’s alpha was measured for internal consistency and Pearson’s correlation coefficients for convergent validity.

Results: Eighteen items were generated with good variability (SD > 1.0) and symmetry (means ranged from −1 to 1) for score distribution. After minor changes to improve content clarity, the amended questionnaire was self-administered among 1196 respondents [mean (SD) age: 38.6 (14.9) years, 51.6% female, 87% >6 years of education]. Six items were dropped due to inadequate item-total correlation coefficients, leaving 12-item scale for factor analysis. Three factors (“benevolence”, “technical competence” and “global trust”) were identified, accounting for 55% of the total variance. Cronbach’s alpha was 0.83, indicating high internal consistency. Convergent validity was demonstrated by statistically significant positive correlations between trust and patients’ satisfaction with pharmacists’ service (r = 0.54), returning for care (r = 0.30) and preference of medical decision-making pattern (r = 0.16).

Conclusion: The 12-item trust in pharmacists scale demonstrated high reliability and convergent validity. Further studies among other populations are suggested to confirm the robustness and even improve the current scale.

Keywords: trust, pharmacist, scale, factor analysis, patient relationship

Creative Commons License This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at and incorporate the Creative Commons Attribution - Non Commercial (unported, v3.0) License. By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms.

Download Article [PDF] 


Readers of this article also read:

Emerging and future therapies for hemophilia

Carr ME, Tortella BJ

Journal of Blood Medicine 2015, 6:245-255

Published Date: 3 September 2015

Green synthesis of water-soluble nontoxic polymeric nanocomposites containing silver nanoparticles

Prozorova GF, Pozdnyakov AS, Kuznetsova NP, Korzhova SA, Emel’yanov AI, Ermakova TG, Fadeeva TV, Sosedova LM

International Journal of Nanomedicine 2014, 9:1883-1889

Published Date: 16 April 2014

Methacrylic-based nanogels for the pH-sensitive delivery of 5-Fluorouracil in the colon

Ashwanikumar N, Kumar NA, Nair SA, Kumar GS

International Journal of Nanomedicine 2012, 7:5769-5779

Published Date: 15 November 2012

A novel preparation method for silicone oil nanoemulsions and its application for coating hair with silicone

Hu Z, Liao M, Chen Y, Cai Y, Meng L, Liu Y, Lv N, Liu Z, Yuan W

International Journal of Nanomedicine 2012, 7:5719-5724

Published Date: 12 November 2012

Cross-linked acrylic hydrogel for the controlled delivery of hydrophobic drugs in cancer therapy

Deepa G, Thulasidasan AK, Anto RJ, Pillai JJ, Kumar GS

International Journal of Nanomedicine 2012, 7:4077-4088

Published Date: 27 July 2012

Crystallization after intravitreal ganciclovir injection

Pitipol Choopong, Nattaporn Tesavibul, Nattawut Rodanant

Clinical Ophthalmology 2010, 4:709-711

Published Date: 14 July 2010