What helps people make values-congruent medical decisions? Eleven strategies tested across six studies

Background: High-quality health decisions are often defined as those that are both evidence-informed and values-congruent. A values-congruent decision aligns with what matters to those most affected by the decision. Values clarification methods are intended to support values-congruent decisions but their effects on values congruence are rarely evaluated.Methods: We tested eleven strategies, including the three most commonly-used values clarification methods, across six between-subjects online randomized experiments in demographically-diverse US populations (n1=1346, n2=456, n3=840, n4=1178, n5=841, n6=2033) in the same hypothetical decision. Our primary outcome was values congruence. Decisional conflict was a secondary outcome in studies 3 through 6.Results: Two commonly-used values clarification methods (pros and cons, rating scales) reduced decisional conflict but did not encourage values-congruent decisions. Strategies using mathematical models to show participants which option aligned with what mattered to them encouraged values-congruent decisions and reduced decisional conflict when assessed.Limitations: A hypothetical decision was necessary for ethical reasons, as we believed some strategies may harm decision quality. Later studies used more outcomes and covariates. Results may not generalize outside US-based adults with online access. We assumed validity and stability of values during the brief experiments.Conclusions: Failing to explicitly support the process of values clarification leads to increased proportions of values-disgruent decisions. Methods representing over half of values clarification methods commonly in use failed to encourage values-congruent decisions. Methods that use models to explicitly show people how options align with their values hold more promise for helping people make decisions aligned with what matters to them. Decisional conflict, while arguably an important outcome in and of itself, is not an appropriate proxy for values congruence.