Traditionally, quality registries have been initiated, developed, and used by physicians essentially for research purposes. There is an unrealized opportunity to expand and strengthen the contribution of quality registries in health care quality improvement. This article aims to characterize quality registry annual reports regarding factors deemed important to process improvement. The 2012 annual reports of the 5 most highly developed Swedish quality registries were examined. Each of the 636 charts included was coded according to an abstraction form. Results show that league tables are highly prevalent, whereas funnel plots and control charts are rare. Health care quality is monitored over time on the basis of few and highly aggregated measurements, and it is usually measured using percentages. In conclusion, quality registry annual reports lack both the level of detail and the consideration of random variation necessary to being able to be systematically used in process improvement. Users of annual reports are recommended caution when discussing differences in quality, both over time and across health care providers, as they can be due to chance and insufficient guidance is provided on the reports in this regard. To better support process improvement, annual reports should thus be more detailed and give more consideration to random variation.