 Knowing what to look for in a hospital can save your life, especially as you age. Patients who are frail and undergoing elective surgeries for things like knee or hip replacements are at a particularly high risk of dying in the days following an operation. Wanting to minimize this risk, a research group from Canada looked at which hospitals were most successful in treating these patients. They found that the best outcomes were in hospitals that saw many frail patients each year. The group looked at data from over 63,000 frail patients who underwent elective surgery at more than 80 hospitals in Ontario. They grouped the hospitals by the number of frail patients cared for in a year and then looked at how survival after surgery related to this patient volume. 100 seemed to be the magic number to reduce the risk of death. Patients seen in hospitals treating 100 or more frail patients a year were much less likely to die within 30 days after surgery than those seen in hospitals treating fewer than 100 frail patients. Although complication rates did not vary between hospitals based on how many frail surgical patients they cared for, frail patients who did experience a complication after surgery were less likely to die as a result if they were cared for in a higher volume hospital. These hospitals were better at recognizing and responding to early warning signs with potentially fatal repercussions. These findings suggest that when frail people are trying to choose a hospital, they should check the number of frail patients that institution serves. Although the researchers weren't able to pinpoint exactly why patient volume was so important, their work will help these patients choose hospitals that are better able to save their lives.