Table 3 Sample characteristics by randomisation group at baseline (7 months)*.
| Variable | Randomisation | |
|---|---|---|
| Control (n = 154) | Intervention (n = 174) | |
| Infant | ||
| Infant age, mean (SD) | 7.3 (0.6) | 7.4 (0.6) |
| Male, n (%) | 89 (58) | 89 (51) |
| Birth weight (g), mean (SD) | 3432 (488) | 3461 (507) |
| Family position, n (%) | ||
| First | 72 (47) | 83 (48) |
| Second | 55 (36) | 54 (31) |
| Third or more | 25 (16) | 37 (21) |
| Exclusively breast feeding (at | 93 (60) | 104 (60) |
| 4 months), n (%) | ||
| Difficult temperament, n (%) | 44 (29) | 40 (23) |
| Infant sleep | ||
| Sleep problem severity, n (%) | ||
| Mild | 37 (24) | 38 (22) |
| Moderate | 58 (38) | 66 (38) |
| Severe | 59 (38) | 70 (40) |
| Number of waking nights/week | ||
| Median (IQR) | 7 (5–7) | 7 (5–7) |
| 0–3, n (%) | 22 (14) | 28 (16) |
| 4–6, n (%) | 44 (29) | 46 (26) |
| 7, n (%) | 88 (57) | 100 (57) |
| Who responds to waking infant overnight? | ||
| Mother, n (%) | 135 (91) | 155 (90) |
| Father, n (%) | 6 (4) | 3 (2) |
| Both parents, n (%) | 8 (5) | 15 (9) |
| Sleep site, n (%) | ||
| Cot in own/sibling's room | 101 (66) | 122 (71) |
| Parent's room | 36 (24) | 30 (17) |
| Parent's bed | 16 (10) | 20 (12) |
| Family | ||
| Maternal age (years), mean (SD) | 33.2 (4.8) | 32.8 (4.3) |
| Relationship status, n (%) | ||
| Married/de facto | 145 (97) | 172 (99) |
| Parents' country of birth | ||
| (mother's/father's), n (%) | ||
| Australia or New Zealand | 124 (81)/ | 139 (80)/ |
| 124 (82) | 137 (79) | |
| Language other than English | 31 (20) | 32 (18) |
| at home, n (%) | ||
| Education status (mother's/ | ||
| father's), n (%) | ||
| Did not complete high school | 28 (18)/43 (28) | 29 (17)/49 (29) |
| Completed high school only | 51 (33)/44 (29) | 53 (30)/45 (26) |
| Completed tertiary/ | 75 (49)/66 (43) | 92 (53)/77 (45) |
| postgraduate degree | ||
| Socioeconomic status (SEIFA | ||
| ranking), n (%) | ||
| Low | 35 (23) | 24 (14) |
| Medium | 41 (27) | 63 (36) |
| High | 78 (51) | 87 (50) |
| Maternal health | ||
| Past history of depression, n (%) | 32 (21) | 36 (21) |
| EPDS | ||
| Mean (SD) | 8.4 (5.1) | 8.4 (5.3) |
| Median (IQR) | 8 (4–12) | 8 (4–12) |
| >9 (n (%)) | 64 (42) | 66 (38) |
| Maternal sleep, n (%) | ||
| Quality | ||
| Fairly/very good | 74 (48) | 77 (44) |
| Very/fairly bad | 80 (52) | 97 (56) |
| Quantity | ||
| Enough/more than enough | 19 (12) | 34 (20) |
| Not nearly/not quite enough | 135 (88) | 140 (80) |
| MCH centres, n | ||
| MCH centre clusters | 24 | 25 |
| Nurses | 31 | 38 |
| Families | 154 | 174 |
| Nurses per MCH centre cluster | ||
| Mean (SD) | 1.35 (0.49) | 1.52 (0.65) |
| Range | 1–2 | 1–3 |
*Sample size ranged from 299 to 328.
EPDS, Edinburgh Postnatal Depression Scale; IQR, interquartile range; MCH, Maternal and Child Health.