Development and Initial Validation of an Instrument to Measure Physician–Pharmacist Collaboration from the Physician Perspective


  • Alan J. Zillich PharmD,

    Corresponding author
    1. Purdue University School of Pharmacy and Pharmacal Sciences, Department of Pharmacy Practice, Indianapolis, IN, USA;
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  • William R. Doucette PhD,

    1. University of Iowa College of Pharmacy, Division of Clinical and Administrative Pharmacy, Iowa City, IA, USA;
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  • Barry L. Carter PharmD, FCCP,

    1. University of Iowa College of Pharmacy, Division of Clinical and Administrative Pharmacy, Iowa City, IA, USA;
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  • Clarence D. Kreiter PhD

    1. University of Iowa Roy J. and Lucille A. Carver College of Medicine, Department of Family Medicine, Iowa City, IA USA;
    2. University of Iowa Office of Consultation and Research in Medical Education, Iowa City, IA, USA
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  • This article was presented in part at the American College of Clinical Pharmacy Annual Meeting in Albuquerque, NM, October 20 to 23, 2002; and as an encore presentation at the American Pharmaceutical Association Annual Meeting and Exposition in New Orleans, LA, March 28 to April 1, 2003.

Alan J. Zillich, Purdue Pharmacy Practice Office, W7555 Myers Bldg., Wishard Health Services, 1001 W 10th Street, Indianapolis, IN 46202-2879, USA. E-mail:


Objective:  Using a conceptual model of collaborative working relationships between pharmacists and physicians, a measure for physician–pharmacist collaboration from the physician perspective was developed. The measure was analyzed for its factor structure, internal consistency, construct validity, and other psychometric properties.

Methods:  An initial 27-item Physician–Pharmacist Collaboration Instrument (PPCI) was developed to assess seven themes about professional relationships using Likert scales. The PPCI was mailed to a random sample of 1000 primary care physicians. Principal component analysis was used to assess the structure and uncover underlying dimensions of the initial instrument. Items were evaluated for inclusion or exclusion into a refined instrument. Internal consistency was assessed by calculating Alpha coefficients for each identified factor. Convergent validity was assessed using Spearman correlations between the identified factors and a previous measure of collaborative care. After measure refinement, confirmatory factor analysis was used to evaluate the fit of both versions of the instrument.

Results:  Three hundred forty usable surveys were returned for a response rate of 34%. Almost 70% of the respondents were male with a mean age of 45.8. A majority were family practice physicians (72.1%) in private practice (67.3%). Three unique factors were identified during principal component analysis and utilized in a confirmatory factor analysis. Both a full and a 14-item reduced model were constructed and tested. Cronbach's alpha for the three factors of the full model ranged from 0.91 to 0.97, while the reliability for the reduced model ranged from 0.86 to 0.96. Comparative fit indexes of 0.97 and 0.98 were obtained, indicating good fit for the models.

Conclusions:  The results indicate good reliability and validity of the refined (14-item) PPCI. This instrument can be useful as a research tool for assessment of the physicians’ perspective about a physician–pharmacist relationship. Further research is warranted to examine if the extent of relationship development, as measured with the PPCI, can affect patient care outcomes.