Table 1.
Estimates of fixed and random effects predicting sleep variables from linear and quadratic change over time, household chaos, and MA or EA (N = 167, in minutes)
| Predictor Variables | Average Nightly Sleep Duration |
Variability in Nightly Sleep Duration |
Average Nightly Sleep Fragmentation |
Variability in Nightly Sleep Fragmentation |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| ||||||||||||
| Infant | Mother | Father | Infant | Mother | Father | Infant | Mother | Father | Infant | Mother | Father | |
| Fixed effects (coefficients) | ||||||||||||
| Intercept | 559.98*** (5.29) | 492.01*** (5.04) | 434.70*** (5.21) | 73.54*** (2.19) | 68.05*** (2.78) | 75.21*** (2.99) | 87.86*** (1.03) | 37.00*** (0.88) | 36.54*** (1.12) | 11.10*** (0.33) | 9.39*** (0.34) | 10.17*** (0.45) |
| Linear Change | 13.07*** (1.87) | −9.12*** (1.72) | −1.30 (1.57) | −2.78** (.94) | −0.72 (1.08) | −3.19** (1.21) | −7.88*** (0.39) | −2.04*** (0.30) | −1.01** (0.36) | −0.70*** (0.15) | −0.18 (0.15) | −0.31+ (0.17) |
| Quadratic Change | −.76*** (.16) | 0.51** (0.15) | 0.09 (0.14) | .05 (.08) | 0.04 (0.10) | 0.22* (0.11) | 0.49*** (0.03) | 0.13*** (0.03) | 0.09** (0.03) | 0.05*** (0.01) | 0.01 (0.01) | 0.02 (0.02) |
| Predictors (coefficients) | ||||||||||||
| Household Chaos | 3.86* (1.58) | 0.33 (1.47) | −1.12 (1.56) | 1.81** (.63) | 2.58** (0.81) | 1.84* (0.88) | 0.63* (0.30) | 0.60* (0.26) | 0.93** (0.33) | 0.15 (0.10) | 0.07 (0.10) | 0.34* (0.13) |
| Linear Change x Chaos | −1.31** (.50) | −0.38 (0.50) | 1.01* (0.46) | .23 (.25) | 0.32 (0.31) | −0.08 (0.35) | −0.13 (0.10) | 0.12 (0.09) | −0.20+ (0.10) | −0.03 (0.04) | 0.05 (0.04) | −0.09+ (0.05) |
| Quadratic Change x Chaos | .10* (.04) | 0.001 (0.04) | −0.08+ (0.04) | −.03 (.02) | −0.04 (0.03) | 0.0001 (0.03) | 0.01 (0.01) | −0.01+ (0.01) | 0.02* (0.01) | 0.001 (0.003) | −0.004 (0.004) | 0.01* (0.004) |
| Controls (coefficients) | ||||||||||||
| Marital Adjustment | −0.27 (0.27) | 0.05 (0.30) | 0.19 (0.13) | −0.17 (0.14) | −0.03 (0.05) | −0.01 (0.06) | −0.01 (0.01) | 0.004 (0.02) | ||||
| Maternal EA at Bedtime | .53 (.39) | −.28* (.13) | −0.01 (0.07) | −0.02 (0.02) | ||||||||
| Random effects (coefficients) | ||||||||||||
| Intercept | 1411.36*** (248.62) | 1202.06*** (218.13) | 1512.94*** (252.04) | 79.68** (38.92) | 240.30*** (52.56) | 213.87*** (53.52) | 43.44*** (8.4) | 38.27*** (6.84) | 63.21*** (10.88) | 0.69 (0.56) | 1.47* (0.62) | 6.63*** (1.44) |
| Model Fit Statistics (−2 Log Likelihood, AIC) | ||||||||||||
| Unconditional Quadratic Growth Model | 7714.81 7734.81 |
7484.00 7504.00 |
6621.57 6641.57 |
6629.02 6649.02 |
6801.39 6821.39 |
6681.73 6701.73 |
5458.06 5478.06 |
5035.28 5055.28 |
5043.63 5063.63 |
4611.03 4631.03 |
3907.73 3927.73 |
3879.04 3879.04 |
| Final Conditional Model | 6098.15 6116.15 |
5158.02 5176.02 |
5048.50 5066.50 |
5212.06 5230.06 |
4656.01 4674.01 |
4690.90 4708.90 |
4300.19 4318.19 |
3441.67 3459.67 |
3590.18 3608.18 |
3121.16 3139.16 |
2659.57 2677.57 |
2822.01 2840.01 |
Note: Standard Errors are in parentheses,
+
p < .10,
*
p < .05,
**
p < .01,
***
p < .001.
Marital adjustment was used as a covariate in analyses of parent sleep. Maternal EA at bedtime was used as a covariate in analyses of infant sleep.