Grant: Project Grant

This emergency department study will assess a new testing process for blood clots in the deep veins of the leg (also known as deep vein thrombosis, or DVT). The best studied tests for blood clots in the legs are complicated. Emergency doctors find the testing process difficult to use and are ordering too many leg scans. When leg scans are used without blood tests, they can wrongly diagnose blood clots in the deep veins and can also miss blood clots in the deep veins. Leg scans are not very user friendly because leg scans can only be scheduled during the daytime. People who are seen by an emergency doctor in the evening or night must return to the emergency department the next day for the scan. This means waiting to be seen in the emergency department twice. Our research group have developed a new, simple testing process which avoids leg scans in almost 1 in 2 people who are tested. The testing process is easy for emergency doctors to use. We found that the new testing process is safe when we applied it to our existing data. We have also evaluated the process in 458 people tested for blood clots in the deep veins. Overall, our new test seems safe and efficient. In this study, we will enroll 4,000 people who visit an emergency department in Canada and are tested for blood clots in the deep veins of the leg. We will use our new testing process to diagnosed blood clots. We will follow up with these people 3 months later to ensure we do not miss a blood clot diagnosis. We expect to find that our new testing process works, is safe and avoids leg scans. Then we can implement the process in Canadian emergency departments.