Search the entire Understanding Patient Data site Search Reducing nationwide variation in stroke prevention and treatment Demonstrating the safety of an anti-obesity medication Using data to ensure the safety of medications Comparing the uptake of emergency operations for heart attack across England The impact of air pollution on health Using pan-European data to understand how air pollution affects health Investigating trends in diabetes across ethnic groups Understanding why diabetes rates vary between ethnic groups Improving treatments for COPD Real-time monitoring of a new treatment for COPD in Salford