The Effect of Shift Structure on Performance: The Role of Fatigue for Paramedics

The effect of shift structure on worker performance and productivity is an issue of increasing interest to firms and regulatory bodies. Using approximately 742,000 emergency medical incidents attended by 2,400 paramedics in the state of Mississippi, we evaluate the extent to which paramedics' performance towards the end of their shift is impacted by its length. We find evidence that their performance deteriorates towards the end of long shifts, and argue that fatigue is the mediating factor. These findings have implications for workforce organization, calling attention to regulation designed to limit extended work hours.