Table 2.
Comparison of interpretable vs. uninterpretable recordings
| Characteristics at time of recording | All | Interpretable | Uninterpretable | |
| n (%) | 83a (100) | 65 (78) | 18 (22) | |
| Corrected gestational age wk, mean (95% CI) | 33.2 (32.6–33.9) | 32.6 (31.9–33.3) | 35.5 (34.2–36.8) | P < 0.001b |
| Weight g, mean (95% CI) | 1725 (1602–1847) | 1588 (1444–1732) | 2204 (1952–2455) | p < 0.001b |
| Head circumference cm, mean (95% CI) | 28.4 (27.8–28.9) | 27.8 (27.1–28.5) | 30.2 (29.0–31.4) | p < 0.001b |
| Chronological age d, mean (95% CI) | 42.4 (37.9–46.9) | 37.1 (32.6–41.7) | 61.4 (52.9–70.0) | p < 0.001b |
| Mode of ventilation, n (%) | ||||
| Room air | 31 (37) | 20 (31) | 11 (61) | |
| Oxyhood | 1 (1) | 1 (2) | 0 (0) | |
| Nasal cannula | 24 (29) | 21 (32) | 3 (17) | |
| Continuous positive airway pressure | 11 (13) | 10 (15) | 1 (6) | |
| Nasal intermittent mandatory ventilation | 6 (7) | 6 (9) | 0 (0) | |
| Intubated | 10 (12) | 7 (11) | 3 (17) | |
| Method of feeding, n (%) | ||||
| No feeding | 9 (10) | 9 (13) | 0 (0) | |
| Orogastric or nasogastric tube | 45 (54) | 38 (58) | 7 (39) | |
| Oral | 29 (35) | 18 (28) | 11 (61) |
aExcludes one recording that could not be accessed. bCalculated using mixed linear model.