Genetic literacy scale: Construct and discriminant validity and population differences

To assess the construct validity of the Genetic Literacy Scale (GLS), establish its discriminant validity in relation to health literacy and numeracy, and examine demographic differences in genetic literacy in a national sample.

A cross-sectional survey was conducted with 650 participants from a nationally representative sample. Confirmatory factor analysis (CFA) was performed to validate the three-factor structure of genetic literacy (familiarity, skills, and knowledge). The heterotrait-monotrait ratio approach was used to assess discriminant validity. Multiple regression analyses examined demographic predictors of genetic literacy.

CFA supported the three-factor structure but identified five problematic items, leading to a refined 25-item version (GLS-25) with improved model fit (CFI = 0.976, RMSEA = 0.040, SRMR = 0.091). Discriminant validity analysis confirmed genetic literacy as distinct from health literacy and numeracy. Regression analyses revealed differences in genetic literacy across demographic groups. Higher educational attainment and income were associated with greater genetic literacy, as was being a non-Hispanic White participant.

This study validates the GLS-25 as a more parsimonious and psychometrically sound measure of genetic literacy. The findings highlight demographic differences in genetic literacy and confirm its distinction from related constructs.

Healthcare providers can use the GLS-25 to screen patients' genetic literacy levels and tailor communication strategies accordingly. This assessment can guide the development of targeted educational materials and support services for populations with lower genetic literacy.