Table 1.
Characteristics of participating units by cluster*
| Unit No | Total annual births | Birth unit | Unit type* | Labour suite midwives | Midwives’ consent (%) |
|---|---|---|---|---|---|
| Experimental (n=19 410) | |||||
| 2 | 3166 | No | 11c | 30 | 102† (100) |
| 4 | 1305 | No | 11c | 48 | 31 (65) |
| 7 | 3324 | Yes | 11c | 27 | Missing data |
| 9 | 1888 | No | 11c | 33 | 31 (94) |
| 10 | 950 | No | 11b | 39 | 25 (64) |
| 12 | 5242 | Yes | 111 | 61 | 35 (57) |
| 14 | 3535 | No | 111 | 26 | 24 (92) |
| Control (n=20 682) | |||||
| 1 | 1042 | No | 11b | NA | NA |
| 3 | 2988 | No | 11c | NA | NA |
| 5 | 4183 | Yes | 111 | NA | NA |
| 6 | 3426 | No | 111 | NA | NA |
| 8 | 3590 | No | 11c | NA | NA |
| 11 | 2710 | Yes | 11c | NA | NA |
| 13 | 2743 | No | 11c | NA | NA |
NA=not applicable.
*11b=consultant led maternity unit with on-site special care baby unit and annual births <1000; 11c=consultant led maternity unit with easy access to neonatal intensive care, adult high dependency, and adult intensive care and annual births 1000-3000; 111=consultant led specialist maternity unit with on-site neonatal intensive care, access to adult intensive care, and annual births >3000.
†Recruitment seems to exceed total number of midwives in one cluster because team model of midwifery care was operating in that unit; this meant that most hospital and community based midwives had labour suite commitment during study period.