Imagine two people: one is completely blind, and the other suffers from intense back pain. Which person would you describe as "healthier"?

A landmark survey launched this summer aims to measure the impact of different diseases, injuries, and risk factors on people's health worldwide, and we welcome your participation.

By taking the survey, you will contribute to our scientific understanding of global health problems and ultimately help policymakers and health care leaders make better decisions based on stronger evidence. The study takes about 15 minutes to complete, and all responses are anonymous.

The survey is part of the Global Burden of Diseases, Injuries, andRisk Factors Study 2010, led by the Institute for Health Metrics and Evaluation at the University of Washington in conjunction with Harvard University, Johns Hopkins University, the University of Queensland, and the World Health Organization.

IHME will post summary survey results online next spring.

Study organizers hope to have 50,000 responses worldwide. Take the survey, and encourage friends and colleagues to take part as well.