Carl van Walraven and Chaim Bell studied more than 2.4 million patient discharges from hospital.1 They found that patients discharged on Fridays were significantly more likely to experience an event (hazard ratio 1.04, 95% confidence interval 1.02–1.05).
Maybe I'm overlooking something, but a hazard ratio of 1.04 does not look very important, although the huge number of patients makes it significant. The hazard is the slope of the survival curve: a measure of how rapidly subjects are readmitted (or die). If the hazard ratio is 2.0, then the rate of readmition or death in one discharge-day group is twice the rate in the other group. If the hazard ratio is 1.02 to 1.05, readmission or death is 1.02 to 1.05 times more likely on Fridays than on Wednesdays. Although this is not nothing, neither is it as dramatic an issue as the title suggests.
Axel Ellrodt American Hospital Paris, France
Reference
- 1.