Higher-order factor analysis of an instrument with dichotomous data

This article reports the use of higher-order factor analysis to examine the underlying dimensions of an instrument designed to measure community acceptance of nurse practitioners/physician's assistants. The instrument consisted of both dichotomous and Likert scale items. Use of factor analysis with dichotomous data is controversial. Higher-order factor analysis provides a potential solution to this dilemma. Following initial factor analysis using maximum likelihood extraction with oblique rotation, the factor correlation matrix was factored to obtain second order factors. The second order factors were interpreted using the factor pattern matrix and examining correlations of individual survey items with the second order factors. This procedure provides additional factorial validity of the underlying uni- and multidimensional concepts related to acceptance of NPs and PAs in rural settings: knowledge, competence, access, and trust.