Oregon made physician-assisted dying legal in 1997. For more than a decade, it was the only state to allow terminally ill patients to ask for—and physicians to provide—a prescription for a lethal dose of medication. Since then, more than 1,500 patients in the state have been granted that request.

Now other states are following Oregon’s example. California and Colorado put similar laws into effect last year, and the District of Columbia enacted its statute in February. That more than triples the number of U.S. citizens who have the legal option to end their lives if they have a terminal illness.

Can Oregon’s 1,500 patients offer lessons about such laws? Oncologist Charles Blanke, professor of medicine at the Oregon Health & Science University, published findings from the state’s data in a recent article for JAMA Oncology. The numbers yielded surprising insights on how the state’s medical system manages pain, hospice and the cost of end-of-life treatment for terminally ill patients.