Do low-numeracy people avoid shared decision making?

OBJECTIVES: Doctors have been increasingly encouraged to involve patients in decision making rather than pursuing the paternalistic model in which they make the decisions for their patients. But do patients want to participate in making decisions about their health? Is there a relationship between their preferences for shared decision making and numeracy skills? Are those preferences different in countries with different medical systems, and for different age groups? Extant studies cannot answer these questions because most are based on nonprobabilistic, highly selective patient samples that prevent generalizations to a broader population. DESIGN: In a survey on probabilistic national samples in the United States and Germany, we interviewed participants with low numeracy skills (Germany: n = 127, mean numeracy = 37; United States: n = 117, mean numeracy = 36) and high numeracy skills (Germany: n = 133, mean numeracy = 96; U.S.: n = 121, mean numeracy = 91). MAIN OUTCOME MEASURES: Usual and preferred role in medical decision making. RESULTS: A significant number of people with low numeracy in both the United States (35%, SE = 8.2) and Germany (30%, SE = 6.1) preferred to be more passive than they currently were. High-numeracy people, in contrast, were mostly satisfied with their current role. On average, Americans were more active than Germans. Middle-aged participants preferred to be more active compared to both younger and older ones. CONCLUSIONS: Shared decision-making preferences are related to numeracy skills, country, and age. Education efforts to increase numeracy, as well as using nonquantitative communication formats, may foster involvement of low-numeracy patients in decisions about their health.