Table 4.

Relationship Satisfaction Prediction by Sleep Imbalance Variables (How Differences in Sleep Between Mother and Father Predict Subsequent Daily Relationship Satisfaction Within Couples)

	b	SE	95% CI		df	t-value	p-value
			Low	High
Objective sleep measures
WASO imbalance model
Intercept	2.57	0.10	2.36	2.77	166.40	24.53	<0.001
WASO imbalance	0.00	0.00	−0.00	0.00	744.20	0.12	0.91
Sex	−0.05	0.12	−0.29	0.19	108.10	−0.40	0.69
WASO imbalance* sex	0.00	0.00	−0.01	0.01	581.70	0.02	0.98
Sleep sufficiency index imbalance model
Intercept	2.60	0.11	2.37	2.82	153.20	22.86	<0.001
Sleep sufficiency index imbalance	0.00	0.00	−0.01	0.01	656.60	−0.21	0.83
Sex	0.07	0.13	−0.19	0.32	98.88	0.52	0.61
Sleep sufficiency index imbalance* sex	−0.01	0.00	−0.02	0.00	509.30	−1.56	0.12
Wake up periods > 1 minute imbalance model
Intercept	2.46	0.11	2.24	2.67	178.02	22.45	<0.001
Wake up periods > 1 minute imbalance	0.02	0.01	−0.00	0.05	731.81	1.93	0.054
Sex	0.02	0.13	−0.23	0.27	118.60	0.17	0.87
Wake up periods > 1 minute imbalance* sex	−0.02	0.02	−0.05	0.02	569.25	−0.95	0.35
Wake up periods > 5 minutes imbalance model
Intercept	2.55	0.10	2.36	2.75	137.41	25.48	<0.001
Wake up periods > 5 minutes imbalance	0.02	0.03	−0.05	0.08	729.57	0.46	0.65
Sex	0.02	0.11	−0.20	0.24	87.52	0.18	0.86
Wake up periods > 5 minutes imbalance* sex	−0.06	0.05	−0.15	0.03	617.26	−1.31	0.19
Waking up first during shared wake periods > 1 minute imbalance model
Intercept	2.62	0.12	2.39	2.85	196.10	22.40	<0.001
Waking up first during shared wake periods > 1 minute imbalance	0.00	0.00	−0.00	0.00	630.70	−0.63	0.53
Sex	−0.16	0.14	−0.43	0.12	129.50	−1.12	0.26
Waking up first during shared wake periods > 1 minute* sex	0.00	0.00	−0.00	0.01	568.40	1.05	0.30
Subjective sleep measures
Sleep sufficiency imbalance model
Intercept	2.71	0.10	2.50	2.91	164.74	26.01	<0.001
Sleep sufficiency imbalance	−0.13	0.05	−0.23	−0.04	695.31	−2.69	0.007
Sex	−0.20	0.12	−0.43	0.04	118.32	−1.64	0.10
Sleep sufficiency imbalance* sex	0.14	0.07	−0.01	0.27	668.44	2.07	0.039
Number of awakenings imbalance model
Intercept	2.61	0.11	2.40	2.82	174.85	24.64	<0.001
Number of awakenings imbalance	−0.03	0.03	−0.09	0.04	717.25	−0.75	0.45
Sex	−0.12	0.12	−0.37	0.12	119.45	−1.00	0.32
Number of awakenings imbalance* sex	0.05	0.05	−0.05	0.14	623.23	0.99	0.32

Notes: Imbalance numbers are undirected, larger numbers mean more imbalance regardless of which parent had more or less. Relationship satisfaction index measured with one question, namely “How satisfied are you with your interaction with your partner today?, ”which was scored by each parent every night between 0–4 with 0 - “not satisfied at all” and 4 - “very satisfied”. WASO and TST measured in minutes. Number of wake periods measured in numbers. Waking up first in shared awakenings was measured as the percentage of total shared awakenings. Sleep sufficiency index measured in percentage. Sleep duration measured in minutes. Subjective sleep sufficiency measured in scale 1–5.

Abbreviations: Sex, the effect of being female; WASO, wake after sleep onset; TST, total sleep time; SE, standard error; CI, confidence interval; IQR, interquartile range; SD, standard deviation.