Validation Study of the Physical Therapist Clinical Performance Instrument VIA Confirmatory Factor Analysis
To assess DPT studentsÕ clinical competence, it is essential that DPT programs and clinical instructors (CIs) have a reliable and valid instrument. The Physical Therapist Clinical Performance Instrument (PT CPI) is the most commonly used instrument to assess DPT studentsÕ clinical competence. CIs and DPT students have raised concerns regarding the reliability and validity of the PT CPI. Specifically, does the PT CPI fully assess the clinical competence of each student, at each clinical experience, and meet the conditions of measurement integrity? Despite these concerns and given the substantial changes in physical therapy practice and education, a validation study of the three factors [professional practice (PP), practice management (PrM), patient management (PtM)] in the current PT CPI (PT CPI: Web) is warranted. The purpose of our investigation was to assess the three-factor PT CPI using confirmatory factor analysis (CFA).
Midterm and final evaluation PT CPI data were analyzed from 703 DPT students first, second, third, and final full-time clinical experiences from three institutions. CFA methods (specification, identification, estimation, fit testing, discriminant validity testing, and model modification) were conducted on the midterm and final evaluation PT CPI data for DPT studentsÕ first three clinical experiences and the final clinical experience at each institution. Data only included CIs ratings on the PT CPI.
Average correlations between factors at midterm and final evaluations were: PP and PtM = 0.81 & 0.86; PP and PrM = 0.82 & 0.83; and PtM and PrM = 0.96 & 0.95. The significant average correlations of 0.96 and 0.95 between the factors PtM and PrM indicated that those two (PtM and PrM) are likely measuring the same construct. Local model fit had significant modification indices for three indicator variables (Professional Development, Accountability, Evaluation), suggesting the model may be improved with the removal of those indicator variables. The PT CPI was then modified to a two-factor model with the removal of three indicator variables (Professional Development, Accountability, and Evaluation) from the three-factor model. Using CFA, the two-factor PT CPI had factors with more acceptable correlations at the midterm (0.84) and final evaluations (0.86), indicating that each factor measures unique aspects of DPT students clinical competence. Chi-squared difference tests at midterm (174.16) and final (100.09) evaluations indicated the two-factor PT CPI was preferred.
Conclusions/Relevance to the conference theme:
Modifying the three-factor PT CPI to the proposed two-factor model may better support DPT students, CIs and programs in the assessment of studentsÕ clinical competence. Our findings provide preliminary evidence to modify the length of the PT CPI, while maintaining instrument integrity. Reliable and valid assessment of DPT studentsÕ clinical competence will increase students and CIs confidence in the assessment of clinical education experiences and promote excellence in physical therapy practice.