Modified discipline-specific epistemological beliefs scale - Lay medical knowledge: Development and validation

Abstract

Scope and Method of Study: The purpose of the study was to modify an existing measure of epistemological beliefs about medical knowledge specific to the layperson and further to investigate the relationship of this epistemological beliefs with other health related constructs, health locus of control and perceived involvement in care. To achieve these purposes, item analysis, confirmatory factor analysis and exploratory factor analysis were conducted to explore the structure of the Modified Domain-Specific Epistemological Beliefs Scale - Lay Medical Knowledge. Psychometric analysis included reliability analysis and evidence in support of content validity was presented. Relationships with other health related constructs were investigated with canonical correlation analysis.

Findings and Conclusions: After item analysis, the confirmatory factor analysis was completed and the data did not appear to fit the theorized model consisting of domains for Certainty of Knowledge, Simplicity of Knowledge, Source of Knowledge, and Justification of Knowledge. As such, exploratory factor analysis was conducted which revealed a three-factor solution interpreted as Simple/Certain, Questioning and Omniscient Authority. Coefficients of internal reliability for all three factors were below .80 indicating that further improvement is needed on the items comprising the scale. The factors of the MDEBS-LMK were related to Health Locus of Control and Perceived Involvement in Care scale factors in predictable ways. The findings support the need for further instrument development, specifically item improvement, improved sampling methodology as the sample was primarily female and highly educated, and a shorter length decreasing the impact of fatigue.