Measuring genetic knowledge: a brief survey instrument for adolescents and adults

Abstract

Basic knowledge of genetics is essential for understanding genetic testing and counseling. The lack of a written, English language, validated, published measure has limited our ability to evaluate genetic knowledge of patients and families. Here, we begin the psychometric analysis of a true/false genetic knowledge measure. The 18-item measure was completed by parents of children with congenital heart defects (CHD) (n=465) and adolescents and young adults with CHD (ages 15-25, n=196) with a mean total correct score of 12.6 (SD=3.5, range 0-18). Utilizing exploratory factor analysis, we determined that one to three correlated factors, or abilities, were captured by our measure. Through confirmatory factor analysis, we determined that the two factor model was the best fit. Although it was necessary to remove two items, the remaining items exhibited adequate psychometric properties in a multidimensional item response theory analysis. Scores for each factor were computed, and a sum-score conversion table was derived. We conclude that this genetic knowledge measure discriminates best at low knowledge levels and is therefore well suited to determine a minimum adequate amount of genetic knowledge. However, further reliability testing and validation in diverse research and clinical settings is needed.

Genetic Knowledge within a National Australian Sample: Comparisons with Other Diverse Populations

“…Researchers have begun to look at subcategories of genetic knowledge [13, 23, 24]. Some emerging categories have included basic physiology of genetics [24], applied knowledge of the relationship between genes, health, and disease [13, 24], the complex mechanisms underlying genetics [13, 23], and procedural/skills relating to genetics and health [23].…”

“…Some emerging categories have included basic physiology of genetics [24], applied knowledge of the relationship between genes, health, and disease [13, 24], the complex mechanisms underlying genetics [13, 23], and procedural/skills relating to genetics and health [23]. A recent study by Fitzgerald-Butt et al [24] conducted a psychometric analysis on an updated version of 18 items often used within clinical groups in the genetic knowledge literature [25-27], first presented by Jallinoja and Aro [12]. Following the removal of two items that did not fit neatly into categories, two underlying latent factors were identified that mapped to categories labelled basic (e.g., characteristics of genes, chromosomes, and gene function) and applied (e.g., the relationship of genes, health and disease) knowledge about genetics.…”

“…This analysis, however, required the removal of two items, and the counterintuitive inclusion of the item “A gene can be seen with the naked eye” into the applied category. Furthermore, other population-based studies have included items that are unrelated to those within Fitzgerald-Butt et al [24] and that may better map onto alternative categories [10, 11, 13]. Thus, it is unclear if the items used by Fitzgerald-Butt et al [24] were diverse enough to capture all potential subtypes of genetic knowledge.…”

“…The attempt of Fitzgerald-Butt et al [24] to identify the structure of genetic knowledge indicates that the literature is in need of consolidation and standardised methods of categorisation to allow between study comparisons of genetic knowledge. These categories should be derived from theoretical frameworks that may emphasise rounded education and/or a reduction in genetic essentialism [28, 29].…”

Genetic Literacy And Attitudes Survey (Iglas): International Population-Wide Assessment Instrument

“…Erby, Roter, Larson, & Cho, 2008;Hooker et al, 2014;Hott et al, 2002;Molster, Charles, Samanek, & O'Leary, 2008;Pearson & Liu-Thompkins, 2012;Saul, 2013). They have also largely focused on well-defined populations such as undergraduate students and young adults (Carver et al, 2017;Fitzgerald-Butt et al, 2016). This research is limited, as it does not provide a comprehensive picture of genetic literacy in the population.…”