TABLE 1.
Parameters included in the severity index (two‐parameter logistic Rasch model)
| Parameter | Criterion | Difficulty | Discrimination |
|---|---|---|---|
| Multiple pregnancies | Yes | –5.20 | –0.31 |
| Preterm | <37 weeks of gestational age | –1.51 | 2.09 |
| Intrauterine growth retardation | Yes | –0.59 | –1.00 |
| Gestational age at birth | ≤34 weeks | –0.38 | 1.65 |
| Acute suffering | Yes | –0.35 | 0.32 |
| Neonatal hospital stay | Yes, with or without intensive care unit | –0.26 | 4.36 |
| Pathological jaundice | Yes | 0.42 | 4.14 |
| Aminoglycosides | Yes | 0.53 | 3.25 |
| Mechanical ventilation (days) | ≥1 day | 1.38 | 3.41 |
| Birth weight | <1500 g | 1.48 | 1.64 |
| Intensive care unit stay (days) | ≥15 days | 2.03 | 3.56 |
| Extrauterine adaptation | Not spontaneous | 2.10 | 0.74 |
| Nosocomial infection | Yes | 2.75 | 1.34 |
| Periventricular leukomalacia | Yes | 2.77 | 1.79 |
| Severe bilateral visual or auditive deficit | Yes | 3.24 | 0.87 |
| Ophthalmological examination at 1 year | No regressive retinopathy of prematurity | 3.42 | 1.76 |
| Toxaemia during pregnancy | Yes | 3.84 | 0.08 |
| Neurological examination at 20 years | Abnormal, with functional deficit | 3.84 | 0.94 |
| Cerebral palsy at 1 year | Yes | 4.28 | 1.03 |
| Neurological examination at 1 year | Abnormal | 5.26 | 0.96 |
| First child | Yes | 5.61 | 0.03 |
| Auditive examination at 1 year | Bilateral deficit | 9.84 | 0.48 |