Table 2.
Summary statistics for mortality, any morbidity, survival with no morbidity and individual morbidities for E1 infants (GA 230–256 weeks), E2 infants (GA 260–296 weeks) and the difference between E1 and E2 infants (E1 – E2). The column labelled 2000 contains the estimated values for the first year of the study period, the column labelled slope contains the rates of change in percent per year and the column labelled 2018 contains the estimate for the last year of the study. The last two columns contain the correlation coefficient between percent and year (r), and the p-value for the correlation coefficients. Morbidities shown are: Chronic Lung Disease (CLD, oxygen at 36 weeks post-conceptional age), any late infection (LI, infection occurring after day three of life), severe intraventricular hemorrhage (sIVH, grades III and IV), severe retinopathy of prematurity (sROP, grades III-V), pneumothorax (PnT), necrotizing enterocolitis (NEC), periventricular leukomalacia (PVL)
| E1 (230 – 256 weeks) | E2 (260 – 296 weeks) | E1 – E2 | |||||||||||||
| 2000a | slopeb | 2018c | r | p | 2000a | slopeb | 2018c | r | p | 2000a | slopeb | 2018c | r | p | |
| Mortality | 43.2 | –0.72 | 30.2 | 0.71 | < 0.001 | 7.6 | –0.17 | 4.5 | 0.53 | 0.020 | 35.6 | –0.55 | 25.7 | 0.61 | 0.006 |
| Morbidity in all patients | 90.1 | –0.83 | 75.2 | 0.84 | < 0.001 | 55.5 | –1.29 | 32.3 | 0.93 | < 0.001 | 34.6 | + 0.46 | 42.9 | 0.77 | < 0.001 |
| Survival with no morbidityd | 14.5 | + 0.9 | 30.7 | 0.82 | < 0.001 | 47.2 | +1.26 | 69.9 | 0.94 | < 0.001 | –32.7 | –0.36 | –39.2 | 0.56 | 0.013 |
| INDIVIDUAL MORBIDITIES (PERCENTAGE OF ALL PATIENTS EVALUATED FOR THE MORBIDITY) | |||||||||||||||
| CLD | 58.5 | –0.52 | 49.1 | 0.53 | 0.020 | 22.3 | –0.33 | 16.4 | 0.61 | 0.006 | 36.1 | –0.20 | 32.5 | 0.23 | 0.34 |
| LI | 49.2 | –1.33 | 25.3 | 0.87 | < 0.001 | 29.6 | –1.23 | 7.5 | 0.94 | < 0.001 | 19.6 | –0.10 | 17.8 | 0.17 | 0.49 |
| sIVH | 25.4 | –0.41 | 18.0 | 0.52 | 0.022 | 7.6 | –0.15 | 4.9 | 0.50 | 0.029 | 17.8 | –0.27 | 12.9 | 0.37 | 0.12 |
| sROP | 28.9 | –0.84 | 13.5 | 0.81 | < 0.001 | 6.0 | –0.24 | 1.7 | 0.85 | < 0.001 | 22.7 | –0.61 | 11.7 | 0.71 | < 0.001 |
| PnT | 11.1 | –0.08 | 9.6 | 0.20 | 0.41 | 4.7 | –0.10 | 2.9 | 0.50 | 0.029 | 6.5 | +0.02 | 6.9 | 0.05 | 0.84 |
| NEC | 10.9 | –0.09 | 9.3 | 0.28 | 0.25 | 7.6 | –0.20 | 4.0 | 0.75 | < 0.001 | 3.4 | +0.11 | 5.4 | 0.37 | 0.12 |
| PVL | 4.3 | +0.03 | 4.8 | 0.09 | 0.71 | 3.0 | –0.05 | 2.1 | 0.38 | 0.11 | 1.3 | +0.08 | 2.7 | 0.25 | 0.30 |
a% in 2000 estimated from y-intercept from linear regression. b% change/year. c% in 2018 estimated from y-intercept from linear regression + 18 x slope. dan increase in percentage from 2000 to 2018 is an improvement