Factorial structure and short version of the Modified Fresno Test to assess the use of evidence-based practice in physiotherapists.

Abstract

Background: The Modified Fresno Test is an adapted version for physiotherapists. So far, none of the versions of the Fresno Test were subjected to analysis of the factorial structure. Objective of the study was describe the exploratory and confirmatory factorial structure of the Modified Fresno Test adapted to the Portuguese-Brazilian and analyze the statistic feasibility for the elaboration of a short version. Methods: The questionnaire was applied in 57 physiotherapists, being 36 professionals (13 of these also professors) and 21 students of the last semester of the physiotherapy course. Exploratory Factor Analysis was performed by the method of principal components. The confirmatory factor analysis was performed by the method of maximum likelihood. The score of the answers in the test and retest was evaluated, totaling 228 observations. Reliability was assessed by means of internal consistency, using Cronbach's alpha coefficient. Results: The internal consistency indicated value of 0.81 for the questions of the instrument. The Kaiser-Meyer-Olkin test presented acceptable values (KMO=0.80). The Bartlett’s sphericity test indicated that the correlations were sufficient for the analysis. The analysis revealed the presence of 3 factors (eigenvalues > 1), which explains 60.9% of total variance of the instrument. In the confirmatory factor analysis, the second model which tested a three-factor structure provided a better fit to the data. Conclusion: The analysis showed good factorial validity and adequate internal consistency for the use of the instrument consisting of 13 questions and 3 factors. This model proved to be better than the original model. The short version consisting of 9 questions may be an appropriate alternative for use in the population of interest.