Aversion to Ambiguity Regarding Medical Tests and Treatments: Measurement, Prevalence, and Relationship to Sociodemographic Factors

Abstract

Aversion to “ambiguity”—uncertainty about the reliability, credibility, or adequacy of risk-related information—is an important problem that may influence judgments and decisions about medical interventions. Ambiguity aversion (AA) varies among individuals, however, and has been understudied in the health domain. To explore this phenomenon further, we developed a new theory-based measure of aversion to ambiguity regarding medical tests and treatments, and examined the prevalence and association of AA with sociodemographic factors. The “AA-Med” scale was developed using a large survey sample of the U.S. public (n = 4,398), and scale psychometric properties and the population distribution of AA were evaluated. The scale demonstrated acceptable reliability (α = .73) and validity as ascertained by association with respondents' interest in a hypothetical ambiguous cancer screening test. Ambiguity aversion (AA) was associated with older age, non-White race, lower education and income, and female sex. The AA-Med scale is a promising new measure, and AA is associated with several sociodemographic factors. We discuss implications of these findings and potential applications of the scale for future research.

We thank Adam Burns, Lamia Khan, Mary Politi, and Deanne Weber for valuable assistance at various stages of this project.

Notes

∗Raw frequencies; total sample N = 4,398 (decreased and unequal n for individual variables due to missing data).

†Percentages weighted to the 2006 U.S. Census.

∗Raw frequencies; total sample N = 4,398 (decreased and unequal n for individual variables due to missing data).

†Percentages weighted to the 2006 U.S. Census.

∗Raw frequencies; total sample N = 4,398 (decreased and unequal n for individual variables due to missing data).

†Range 1–5.

∗Model N = 4,287 due to missing data.

†Age, sex, race, education, income.

∗Weighted to the 2006 U.S. Census, total sample N = 4,398 (decreased and unequal n for individual variables due to missing data).

†High AA defined as scale scores ≥4 on the 5-point scale.

‡Range 1–5.

¹Reverse-scored item.

Five-point numeric response scale for all items, with end points labeled “strongly disagree” and “strongly agree.”

¹Four-point response scale for all items: “very unwilling,” “somewhat unwilling,” “somewhat willing.” “very willing.”