Baseline characteristics according to hospital volume and surgeon volume (n = 11677).

*One way ANOVA test for continuous variable (mean age); Pearson’s chi-square test for categorical variables.†Cutoff point for hospital 65 cases for female breast cancer; 61 cases for colorectal cancer; 62 cases for lung cancer; 41 cases for prostate cancer; and 78 cases for head and neck cancer.‡Cutoff point for surgeon volume: 15 cases for female breast cancer; 14 cases for colorectal cancer; 6 cases for lung cancer; 8 cases for prostate cancer; and 9 cases for head and neck cancer.