Table 2.
Primary and secondary outcomes
| Decision support (n=23 263) | No decision support (n=23 351) | Adjusted risk ratio (CI) | ||
|---|---|---|---|---|
| Composite neonatal primary outcome | ||||
| Composite primary outcome* | 172 (0·7%) | 171 (0·7%) | 1·01 (95% CI 0·82–1·25) | |
| Intrapartum stillbirths† | 1 (0) | 2 (0) | 0·50 (95% CI 0·05–5·53) | |
| Neonatal deaths up to 28 days after birth‡ | 6 (0) | 4 (0) | 1·51 (95% CI 0·42–5·33) | |
| Moderate or severe neonatal encephalopathy (requiring cooling) | 18 (0·1%) | 21 (0·1%) | 0·86 (95% CI 0·46–1·61) | |
| Admission to neonatal unit within 48 h of birth for ≥48 h because of feeding difficulties, respiratory illness or symptoms, or encephalopathy and evidence of compromise at birth | 147 (0·6%) | 144 (0·6%) | 1·02 (95% CI 0·81–1·29) | |
| Other neonatal outcomes | ||||
| Admission to a higher level of care | 1389 (6·0%) | 1429 (6·1%) | 0·98 (99% CI 0·89–1·08) | |
| Apgar score <4 at 5 min | 43 (0·2%) | 65 (0·3%) | 0·67 (99% CI 0·40–1·11) | |
| Cord artery pH | ||||
| <7·15 | 1625 (11·3%) | 1695 (11·8%) | 0·96 (99% CI 0·88–1·04) | |
| <7·05 | 268 (1·9%) | 278 (1·9%) | 0·95 (99% CI 0·77–1·19) | |
| Mean (SD) | 7·24 (0·08) | 7·24 (0·08) | ·· | |
| Unknown | 8829 | 8981 | ·· | |
| Metabolic acidosis§ | ||||
| Yes | 148 (1·1%) | 131 (1·0%) | 1·12 (99% CI 0·82–1·52) | |
| No | 13 538 (98·9%) | 13 533 (99·0%) | ·· | |
| Unknown | 9577 | 9687 | ·· | |
| Resuscitation | ||||
| None | 18 457 (87·3%) | 18 605 (87·6%) | ·· | |
| One intervention | 2139 (10·1%) | 2116 (10·0%) | 1·03¶ (99% CI 0·96–1·09) | |
| Two or more interventions | 554 (2·6%) | 524 (2·5%) | ·· | |
| Unknown | 2113 | 2106 | ·· | |
| Seizures in hospital | 39 (0·2%) | 41 (0·2%) | 0·95 (99% 0·54–1·70) | |
| Destination of baby immediately after birth | ||||
| Postnatal ward | 21 571 (93·6%) | 21 664 (93·6%) | ·· | |
| Home | 467 (2·0%) | 485 (2·1%) | 1·00|| (99% CI 0·99–1·00) | |
| Transitional care unit | 277 (1·2%) | 235 (1·0%) | ·· | |
| Neonatal unit | 653 (2·8%) | 690 (3·0%) | ·· | |
| Transferred hospital | 4 (0) | 7 (0) | ·· | |
| Stillbirth | 1 (0) | 2 (0) | ·· | |
| Other | 69 (0·3%) | 53 (0·2%) | ·· | |
| Median length of hospital stay, days | 2 (1–3) | 2 (1–3) | 0·99** (99% CI 0·97–1·01) | |
| Delivery outcomes | ||||
| Mode of delivery | ||||
| Spontaneous cephalic vaginal | 11 823 (50·8%) | 11 959 (51·2%) | 0·99 (99% CI 0·97–1·01) | |
| Caesarean section | 5669 (24·4%) | 5555 (23·8%) | ·· | |
| Instrumental | 5698 (24·5%) | 5765 (24·7%) | ·· | |
| Vaginal breech | 73 (0·3%) | 72 (0·3%) | ·· | |
| Indications for any operative intervention (caesarean section and instrumental delivery) | ||||
| Fetal distress | 4278 (18·4%) | 4262 (18·3%) | 1·04† † (99% CI 1·00–1·08) | |
| Failure to progress | 5059 (21·8%) | 5175 (22·2%) | 1·01† † (99% CI 0·97–1·05) | |
| Fetal distress and failure to progress | 1774 (7·6%) | 1599 (6·9%) | ·· | |
| Other reason | 229 (1·0%) | 247 (1·1%) | ·· | |
| Indication for instrumental vaginal deliveries | ||||
| Fetal distress | 2608 (11·2%) | 2559 (11·0%) | 1·03† † (99% CI 0·97–1·09) | |
| Failure to progress | 2262 (9·7%) | 2396 (10·3%) | 0·97† † (99% CI 0·91–1·03) | |
| Fetal distress and failure to progress | 700 (3·0%) | 660 (2·8%) | ·· | |
| Other reason | 117 (0·5%) | 134 (0·6%) | ·· | |
| Caesarean section | ||||
| Grade 1 (immediate threat to life) | 1138 (4·9%) | 1121 (4·8%) | 1·02‡ ‡ (99% CI 0·92–1·13) | |
| Grade 2 (some threat of compromise) | 3754 (16·2%) | 3605 (15·5%) | 1·04‡ ‡ (99% CI 0·99–1·09) | |
| Grade 3 (no threat of compromise) | 645 (2·8%) | 689 (3·0%) | 1·02‡ ‡ (99% CI 0·98–1·07) | |
| Grade 4 (elective) | 12 (0·1%) | 12 (0·1%) | ·· | |
| Episiotomy§§ | ||||
| Yes | 6396 (28·9%) | 6498 (29·3%) | 0·99 (99% CI 0·95–1·03) | |
| Unknown | 826 | 840 | ·· | |
| Any episode of fetal blood sampling§§ | 2366 (10·3%) | 2187 (9·5%) | 1·08 (99% CI 1·01–1·16) | |
| Destination of mother immediately after birth§§ | ||||
| Ward | 21 554 (94·6%) | 21 614 (94·5%) | ·· | |
| Home | 429 (1·9%) | 462 (2·0%) | 1·00¶¶ (99% CI 0·99–1·00) | |
| Intensive-care unit | 15 (0·1%) | 19 (0·1%) | ·· | |
| High-dependency unit | 793 (3·5%) | 768 (3·4%) | ·· | |
| Theatre | 0 (0) | 0 (0) | ·· | |
| Other hospital | 0 (0) | 8 (0) | ·· | |
| Admission to a higher level of care§§ | 1245 (5·4%) | 1193 (5·2%) | 1·05 (99% CI 0·95–1·16) | |
| Duration of labour | ||||
| No labour | 378 | 371 | ·· | |
| Seemingly randomised after delivery | 92 | 120 | ·· | |
| Length of labour from trial entry (min)|||| | ||||
| Geometric mean and geometric mean ratio | 379 | 381 | 0·99 (99% CI 0·98–1·01) | |
| Median | 404 (234–638) | 408 (236–640) | ·· | |
| Unknown | 871 | 924 | ·· | |
| Length of first stage from trial entry (min)|||| | ||||
| Geometric mean and geometric mean ratio | 169 | 168 | 1·01 (99% CI 0·98–1·04) | |
| Median | 200 (100–351) | 201 (96–354) | ·· | |
| Unknown | 6422 | 6292 | ·· | |
| Length of second stage from trial entry (min)|||| | ||||
| Geometric mean and geometric mean ratio | 39 | 39 | 0·99 (99% CI 0·96–1·03) | |
| Median | 49 (15–113) | 50 (16–114) | ·· | |
| Unknown | 6036 | 5934 | ·· | |
Data are n (%), n, or median (IQR), unless otherwise specified. Missing data are <1% unless otherwise presented. Risk ratios were adjusted for stratification factors used in the randomisation (centre and twin birth) and clustering because of twins and multiple birth episodes. Minimisation factors were not adjusted for in the analysis of intrapartum stillbirths, neonatal deaths, and neonatal encephalopathy because of the small number of events. Crude effect measures were not presented as identical to one decimal place (two decimal places for most outcomes). CI=confidence interval.
The components of the primary outcome are mutually exclusive and outcomes listed higher take precedence over those listed below them—eg, if a baby with neonatal encephalopathy died within 28 days, the outcome would be recorded as neonatal death.
Excludes stillbirths due to congenital anomalies.
Excludes deaths due to congenital anomalies; deaths after hospital discharge not reported for Ireland.
Cord artery pH <7·05, base deficit ≥12mmol/L.
Risk ratio of one or more interventions vs none.
Risk ratio of ward or home vs all other destinations (if known).
This figure is a hazard ratio rather than a risk ratio.
Risk ratio for fetal distress and risk ratio for failure to progress include (in the numerator) deliveries in the third category for which both fetal distress and failure to progress were recorded.
Risk ratios based on cumulative totals for grade—ie, grade 1 vs all other deliveries, grade 1–2 vs all other deliveries, and grade 1–3 vs all other deliveries.
n=22 987 in the decision-support group and 23 055 in the no-decision-support group (ie, the number of women, rather than the number of infants) for all outcomes after this row.
Risk ratio of ward or home vs all other destinations (if known).
Denominators exclude women with no labour, seemingly randomised after delivery, and unknown length of labour.