Within the UHC system, discharge from a medical service was associated with higher average rates of readmission at 7, 14, and 30-days (2.51%, 4.20%, and 6.55%) when compared to discharge from a surgical service (1.84% 2.88%, and 4.17%) (p<0.001 for all by two-sided Wilcoxon rank-sum test). Error bars represent one standard deviation.