Table 2:
Unadjusted Length of Stay (Days) Stratified by Gestational Age and Birthweight
| TOTAL | FERTILE (F) | SUBFERTILE (S) | ART (A) | P-value S vs F | P-value A vs F | P-value A vs S | Overall P-value | ||
|---|---|---|---|---|---|---|---|---|---|
| N=345,756 | N= 332,481 | N = 4,987 | N = 8,288 | ||||||
| Overall | Mean (SE) median (IQR) |
3.83 (0.01) 2 (2, 4) |
3.79 (0.01) 2 (2, 4) |
4.32 (0.05) 3 (2, 4) |
4.90 (0.04) 3 (2, 4) |
<0.001 | <0.001 | <0.001 | <0.001 |
| Gestational Age | |||||||||
| 23–27 wks | N (kids) Mean (SE) median (IQR) |
792 98.60 (1.24) 95 (76, 115) |
739 98.40 (1.23) 94 (76, 115) |
15 101.67 (8.94) 98 (83, 116) |
38 101.32 (5.60) 100 (89, 122) |
0.71 | 0.61 | 0.97 | 0.82 |
| 28–33 wks | N (kids) Mean (SE) median (IQR) |
4210 36.62 (0.37) 31 (20, 47) |
3925 36.53 (0.34) 31 (20, 47) |
87 36.24 (2.26) 28 (19, 46) |
198 38.76 (1.60) 34 (21, 49) |
0.90 | 0.16 | 0.37 | 0.36 |
| 34–36 wks | N (kids) Mean (SE) median (IQR) |
16760 7.26 (0.08) 4 (2, 9) |
15836 7.25 (0.05) 4 (2, 9) |
305 6.78 (0.33) 4 (3, 8) |
619 7.68 (0.26) 5 (3, 10) |
0.18 | 0.1 | 0.037 | 0.097 |
| 37–38 wks | N (kids) Mean (SE) median (IQR) |
72491 3.28 (0.02) 2 (2, 4) |
69285 3.27 (0.01) 2 (2, 4) |
1242 3.47 (0.06) 3 (2, 4) |
1964 3.41 (0.05) 3 (2, 4) |
0.0004 | 0.0025 | 0.37 | <0.0001 |
| ≥39 wks | N (kids) Mean (SE) median (IQR) |
251503 2.91 (0.01) 2 (2, 4) |
242696 2.90 (0.00) 2 (2, 4) |
3338 3.13 (0.03) 3 (2, 4) |
5469 3.22 (0.02) 3 (2, 4) |
<0.0001 | <0.0001 | 0.012 | <0.0001 |
| Birthweight | |||||||||
| ≤1000 g | N (kids) Mean (SE) median (IQR) |
919 94.87 (1.18) 91 (71, 112) |
860 94.41 (1.16) 90 (70, 112) |
18 99.00 (8.40) 96 (83, 106) |
41 102.68 (5.77) 101 (89, 122) |
0.58 | 0.14 | 0.72 | 0.29 |
| 1001–1500 g | N (kids) Mean (SE) median (IQR) |
1458 50.56 (0.67) 46 (34, 61) |
1366 50.44 (0.60) 46 (34, 61) |
22 52.45 (4.89) 47 (28, 76) |
70 52.27 (2.73) 49 (37, 64) |
0.68 | 0.51 | 0.97 | 0.74 |
| 1501–2500 g | N (kids) Mean (SE) median (IQR) |
16579 10.54 (0.11) 5 (2, 14) |
15770 10.44 (0.08) 5 (2, 14) |
285 12.05 (0.70) 6 (4, 17) |
524 12.80 (0.55) 7 (4, 17) |
0.014 | <.0001 | 0.40 | <.0001 |
| ≥2501 g | N (kids) Mean (SE) median (IQR) |
326800 3.02 (0.01) 2 (2, 4) |
314485 3.01 (0.00) 2 (2, 4) |
4662 3.25 (0.03) 3 (2, 4) |
7653 3.40 (0.02) 3 (2, 4) |
<0.0001 | <0.0001 | <0.0001 | <0.0001 |
Mean length of stay (days) and Standard Error (SE) represent the unadjusted model using gamma distribution; IQR (Interquartile Range)