Table 1.
Sleep values for each variable from the BISQ at 5, 9, and 12 months and their correlations with negative reactivity and maternal stress at 5 months.
| Sleep variable | Age (months) | Mean (SD) | Correlations (r) | |
|---|---|---|---|---|
| Negative reactivity | Maternal stress | |||
| Night sleep duration (in hours) | 5 | 9.50 (1.39) [F = 9.66 (1.31); M = 9.36 (1.47)] | 0.19 | −0.08 |
| 9 | 9.93 (1.26) [F = 9.39 (1.26); M = 10.40 (1.07)] | 0.03 | 0.04 | |
| 12 | 10.25 (1.02) [F = 10.01 (0.89); M = 10.46 (1.10)] | −0.11 | −0.05 | |
| Day sleep duration (in hours) | 5 | 3.45 (1.49) [F = 3.25 (1.51); M = 3.62 (1.49)] | 0.03 | 0.25 |
| 9 | 3.35 (1.31) [F = 3.28 (1.66); M = 3.40 (0.96)] | 0.05 | −0.08 | |
| 12 | 2.99 (1.04) [F = 2.97 (1.18); M = 3.00 (0.94)] | 0.07 | −0.10 | |
| Night wakings | 5 | 1.24 (1.13) [F = 0.89 (0.81); M = 1.55 (1.29)] | 0.16 | 0.12 |
| 9 | 0.96 (0.95) [F = 1.00 (1.00); M = 0.93 (0.94)] | 0.40* | 0.23 | |
| 12 | 0.91 (1.19) [F = 0.89 (1.37); M = 0.93 (1.04)] | 0.21 | 0.01 | |
| Night wakefulness (in minutes) | 5 | 39.32 (73.80) [F = 55.76 (107.12); M = 26.00 (21.94)] | 0.12 | −0.04 |
| 9 | 23.87 (26.56) [F = 28.94 (31.32); M = 19.76 (21.94)] | 0.35* | 0.05 | |
| 12 | 19.61 (29.57) [F = 24.53 (36.68); M = 15.62 (22.45)] | 0.12 | −0.01 | |
| Sleep latency (in minutes) | 5 | 23.38 (21.70) [F = 27.33 (26.60); M = 20.00 (16.35)] | 0.49* | 0.11 |
| 9 | 20.36 (14.73) [F = 28.61 (17.05); M = 13.29 (7.16)] | 0.24 | 0.04 | |
| 12 | 22.74 (17.47) [F = 28.61 (22.15); M = 17.71 (10.28)] | 0.13 | 0.05 | |
| Extent of infant’s sleep problems | 5 | 1.15 (0.36) [F = 1.21 (0.42); M = 1.10 (0.30)] | −0.03 | 0.07 |
| 9 | 1.25 (0.42) [F = 1.37 (0.50); M = 1.14 (0.48)] | 0.34* | −0.07 | |
| 12 | 1.23 (0.48) [F = 1.21 (0.42); M = 1.24 (0.54)] | 0.20 | 0.03 | |
F = females; M = males.
*
p < 0.05.