The purpose of this paper was to examine national differences in the desire to participate in decision-making of people with severe mental illness in six European countries.

The data was taken from a European longitudinal observational study (CEDAR; ISRCTN75841675). A sample of 514 patients with severe mental illness from the study centers in Ulm, Germany, London, England, Naples, Italy, Debrecen, Hungary, Aalborg, Denmark and Zurich, Switzerland were assessed as to desire to participate in medical decision-making. Associations between desire for participation in decision-making and center location were analyzed with generalized estimating equations.

We found large cross-national differences in patients’ desire to participate in decision-making, with the center explaining 47.2% of total variance in the desire for participation (P < 0.001). Averaged over time and independent of patient characteristics, London (mean = 2.27), Ulm (mean = 2.13) and Zurich (mean = 2.14) showed significantly higher scores in desire for participation, followed by Aalborg (mean = 1.97), where scores were in turn significantly higher than in Debrecen (mean = 1.56). The lowest scores were reported in Naples (mean = 1.14). Over time, the desire for participation in decision-making increased significantly in Zurich (b = 0.23) and decreased in Naples (b = −0.14). In all other centers, values remained stable.

This study demonstrates that patients’ desire for participation in decision-making varies by location. We suggest that more research attention be focused on identifying specific cultural and social factors in each country to further explain observed differences across Europe.