Factor analysis as a tool for survey analysis using a professional role orientation inventory as an example

The purpose of this article is to illustrate how confirmatory factor analysis can be used to extend and clarify a researcher's insight into a survey instrument beyond that afforded through the typical exploratory factor analytic approach. The authors use as an example a survey instrument developed to measure individual differences in professional role orientation among physical therapists, the Professional Role Orientation Inventory for Physical Therapists (PROI-PT).

Five hundred three physical therapists responded to a mail survey instrument that was sent to a random sample of 2,000 American Physical Therapy Association members.

An adapted version of the Professional Role Orientation Inventory, a 40-item Likert-scale instrument developed to assess professional role orientation on 4 dimensions (authority, responsibility, agency, and autonomy), was used. Exploratory and confirmatory factor analyses were used to examine the factorial validity of the PROI-PT.

Exploratory factor analysis served as a starting point for examining the factor structure of the instrument. Confirmatory factor analysis then was used to test the hypothesized factor structure and to suggest refinements to the PROI-PT that would improve a psychometric property (internal consistency).

Although further refinement of the PROI-PT is needed, an instrument that yields valid and reliable measurements of individual differences in professionalism among physical therapists could further our understanding of the psychosocial aspects of physical therapist practice. Exploratory and confirmatory factor analyses can be used by researchers who study various psychosocial constructs in physical therapy.