Surgery day of the week | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Monday | Tuesday | Wednesday | Thursday | Friday | |||||||
n = 18,893 | n = 29,313 | n = 32,289 | n = 33,088 | n = 33,027 | |||||||
n | (%) | n | (%) | n | (%) | n | (%) | n | (%) | P-value | |
Female sex | 18,868 | (100) | 29,291 | (100) | 32,260 | (100) | 33,062 | (100) | 33,001 | (100) | 0.24 |
Age category | <0.001 | ||||||||||
<40 | 939 | (5.0) | 1,384 | (4.7) | 1,586 | (4.9) | 1,725 | (5.2) | 1,730 | (5.2) | |
40-49 | 4,351 | (23) | 6,806 | (23) | 7,430 | (23) | 7,891 | (24) | 8,018 | (24) | |
50-59 | 4,060 | (21) | 6,336 | (22) | 7,099 | (22) | 7,244 | (22) | 7,306 | (22) | |
60-69 | 4,993 | (26) | 7,930 | (27) | 8,582 | (27) | 8,694 | (26) | 8,552 | (26) | |
70-79 | 3,251 | (17) | 4,889 | (17) | 5,330 | (17) | 5,458 | (16) | 5,266 | (16) | |
≥80 | 1,299 | (6.9) | 1,968 | (6.7) | 2,262 | (7.0) | 2,076 | (6.3) | 2,155 | (6.5) | |
BMI, kg/m2 | 0.019 | ||||||||||
<18.5 | 1,646 | (8.7) | 2,668 | (9.1) | 2,792 | (8.6) | 2,858 | (8.6) | 2,950 | (8.9) | |
18.5-21.9 | 6,877 | (36) | 10,780 | (37) | 11,754 | (36) | 12,183 | (37) | 12,193 | (37) | |
22.0-24.9 | 5,410 | (29) | 8,251 | (28) | 9,248 | (29) | 9,276 | (28) | 9,372 | (28) | |
25.0-29.9 | 3,701 | (20) | 5,800 | (20) | 6,451 | (20) | 6,679 | (20) | 6,376 | (19) | |
≥30 | 1,040 | (5.5) | 1,578 | (5.4) | 1,734 | (5.4) | 1,788 | (5.4) | 1,830 | (5.5) | |
Missing | 219 | (1.2) | 236 | (0.8) | 310 | (1.0) | 304 | (0.9) | 306 | (0.9) | |
Past/current smoker | 3,488 | (18) | 5,875 | (20) | 6,050 | (19) | 6,912 | (21) | 6,796 | (21) | <0.001 |
Comorbidities | |||||||||||
CCI | <0.001 | ||||||||||
2 | 15,946 | (84) | 25,260 | (86) | 27,635 | (86) | 28,808 | (87) | 28,402 | (86) | |
3 | 2,303 | (12) | 3,168 | (11) | 3,477 | (11) | 3,255 | (9.8) | 3,658 | (11) | |
>4 | 644 | (3.4) | 885 | (3.0) | 1,177 | (3.6) | 1,025 | (3.1) | 967 | (2.9) | |
Hypertension | 1,631 | (8.6) | 2,543 | (8.7) | 2,899 | (9.0) | 2,723 | (8.2) | 2,695 | (8.2) | 0.001 |
Schizophrenia | 71 | (0.4) | 158 | (0.5) | 160 | (0.5) | 176 | (0.5) | 168 | (0.5) | 0.11 |
Preoperative drug use | |||||||||||
Insulin | 435 | (2.3) | 700 | (2.4) | 746 | (2.3) | 734 | (2.2) | 828 | (2.5) | 0.16 |
Oral hypoglycemic | 435 | (2.3) | 655 | (2.2) | 618 | (1.9) | 675 | (2.0) | 661 | (2.0) | 0.008 |
Heparin | 238 | (1.3) | 278 | (0.9) | 310 | (1.0) | 357 | (1.1) | 339 | (1.0) | 0.008 |
Clinical cancer stage | <0.001 | ||||||||||
0 | 2,466 | (13) | 4,144 | (14) | 4,512 | (14) | 4,540 | (14) | 4,905 | (15) | |
1 | 11,231 | (59) | 17,457 | (60) | 19,685 | (61) | 19,721 | (60) | 19,616 | (59) | |
2 | 3,835 | (20) | 5,726 | (20) | 6,160 | (19) | 6,572 | (20) | 6,284 | (19) | |
3 | 160 | (0.8) | 256 | (0.9) | 262 | (0.8) | 223 | (0.7) | 249 | (0.8) | |
Missing | 1,201 | (6.4) | 1,730 | (5.9) | 1,670 | (5.2) | 2,032 | (6.1) | 1,973 | (6.0) | |
Sentinel biopsy | 15,730 | (83) | 24,775 | (85) | 27,700 | (86) | 28,250 | (85) | 28,495 | (86) | <0.001 |
Teaching hospital | 16,844 | (89) | 26,587 | (91) | 32,289 | (100) | 33,088 | (100) | 33,027 | (100) | <0.001 |
Hospital volume | <0.001 | ||||||||||
Low (<77) | 5,979 | (32) | 8,763 | (30) | 9,106 | (28) | 10,227 | (31) | 8,249 | (25) | |
Medium (78-167) | 5,933 | (31) | 9,336 | (32) | 13,598 | (42) | 11,634 | (35) | 12,181 | (37) | |
High (≥168) | 6,981 | (37) | 11,214 | (38) | 9,585 | (30) | 11,227 | (34) | 12,597 | (38) |
Surgery day of the week | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Monday | Tuesday | Wednesday | Thursday | Friday | ||||||||
n = 18,893 | n = 29,313 | n = 32,289 | n = 33,088 | n = 33,027 | P-value | |||||||
Postoperative length of stay, days | 4 | (2-6) | 4 | (3-6) | 4 | (3-6) | 4 | (3-6) | 4 | (3-6) | <0.001 | |
Total length of stay, days | 7 | (5-9) | 6 | (5-8) | 6 | (5-8) | 6 | (5-8) | 6 | (5-8) | <0.001 | |
Total hospitalization costs, US dollar | 6,127 | (5,639-6,711) | 6,058 | (5,572-6,629) | 6,124 | (5,597-6,648) | 6,143 | (5,642-6,673) | 6,137 | (5,604-6,692) | <0.001 | |
Postoperative complications | 707 | (3.7) | 815 | (2.8) | 1,100 | (3.4) | 1,000 | (3.0) | 1,234 | (3.7) | <0.001 |
Surgery day of the week | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Monday | Tuesday | Wednesday | Thursday | |||||||||
IRR* | 95%CI | P-value | IRR* | 95%CI | P-value | IRR* | 95%CI | P-value | IRR* | 95%CI | P-value | |
Postoperative length of stay, days | 0.98 | (0.97 to 0.98) | <0.001 | 0.99 | (0.98 to 0.99) | <0.001 | 0.99 | (0.986 to 0.997) | 0.003 | 1.00 | (0.99 to 1.00) | 0.82 |
Total length of stay, days | 1.10 | (1.09 to 1.10) | <0.001 | 1.02 | (1.02 to 1.03) | <0.001 | 1.00 | (0.99 to 1.00) | 0.29 | 1.00 | (0.99 to 1.00) | 0.64 |