In-hospital stroke mortality, hospital transfers, and referral bias at a rural academic medical center

A chart review of acute stroke (DRG 14) discharges from a rural academic medical center in 1999 was performed because of an observed high in-hospital crude acute stroke mortality rate. An analysis of the results of this chart review demonstrated that the odds ratio of intracerebral hemorrhage in patients who had been transferred from other hospitals was 11.7 compared to intracerebral hemorrhage in nonhospital transfer patients (p < 0.00001). This finding illustrates the potential magnitude and significance of referral bias at a rural academic medical center.