Abstract: Using a newly constructed dataset on German hospitals, which includes 24 process and outcome indicators of clinical quality, we test whether quality has increased in various clinical areas since the introduction of mandatory quality reports and the online publication of part of the collected quality measures. Our results suggest that process indicators of clinical quality have increased significantly in 2008 compared to 2006. In addition, the hospitals underperforming in 2006 appear to have increased their clinical quality relatively more than the other hospitals. When instead quality is measured by outcome indicators, average clinical quality is estimated to have increased for underperforming hospitals and decreased for the best ...