Table 2B.
Results of multilevel models testing the temporal associations of daily cognitive interference with nightly sleep variables
| Nightly sleep (Day ) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Bedtimes (military hours2) |
Wake Times (military hours) |
Sleep Duration (in hours) |
Sleep Quality (1 to 5:better) |
Sleep Latency (in minutes) |
||||||
| B | (SE) | B | (SE) | B | (SE) | B | (SE) | B | (SE) | |
| Fixed Effects | ||||||||||
| Intercept | −0.99*** | (0.15) | 6.49*** | (0.20) | 6.95*** | (0.14) | 3.09*** | (0.07) | 16.93*** | (1.94) |
| Cognitive interference (CI; 0 = never to 4 = very often) | ||||||||||
| Between-person, Average CI | 0.15 | (0.17) | −0.05 | (0.23) | −0.08 | (0.17) | −0.25** | (0.08) | 0.77 | (2.28) |
| Within-person lagged (Day ), Same day's CI | −0.19 * | (0.09) | −0.30 ** | (0.11) | −0.10 | (0.10) | −0.01 | (0.05) | 0.31 | (1.26) |
| Covariates | ||||||||||
| Previous night's sleep (Day -1) | −0.03 | (0.04) | −0.12** | (0.04) | −0.29*** | (0.04) | −0.35*** | (0.04) | −0.34*** | (0.03) |
| Age (in years) | −0.03† | (0.01) | −0.03† | (0.02) | 0.01 | (0.01) | −0.004 | (0.01) | 0.01 | (0.17) |
| Gender, Men (vs. women) | 0.09 | (0.16) | −0.06 | (0.22) | −0.35* | (0.16) | −0.11 | (0.08) | 2.46 | (2.12) |
| Race, White (vs. non-white) | 0.04 | (0.17) | 0.07 | (0.23) | 0.15 | (0.16) | 0.01 | (0.08) | 2.47 | (2.22) |
| Education, Less than college (vs. college graduates) | −0.38* | (0.19) | −0.49† | (0.26) | −0.10 | (0.19) | −0.05 | (0.09) | −1.79 | (2.51) |
| Marital status, Single (vs. married/partnered) | 0.48† | (0.25) | 0.10 | (0.34) | −0.85*** | (0.24) | −0.02 | (0.12) | 6.92* | (3.27) |
| Work hours | 0.14** | (0.05) | 0.03 | (0.07) | −0.16** | (0.05) | −0.02 | (0.02) | −0.05 | (0.68) |
| Random Effects | ||||||||||
| Person level variance | 0.49*** | (0.10) | 0.91*** | (0.18) | 0.15 | (0.13) | 0.01 | (0.04) | 45.10* | (23.13) |
| Auto-correlation1 | 0.19* | (0.07) | 0.24*** | (0.05) | 0.44*** | (0.06) | 0.45*** | (0.06) | 0.40*** | (0.06) |
| Residual variance | 1.18*** | (0.08) | 1.89*** | (0.13) | 1.73*** | (0.16) | 0.47*** | (0.05) | 280.8*** | (27.13) |
Note. 869-867 days from 130 employees; 8 consecutive days' data were nested within each employee. Tables 2A and 2B represent one bidirectional model. Results are presented for each outcome (cognitive interference in 2A and sleep variables in 2B) separately across Tables 2A and B for ease of interpretation. As the two competing temporal directions in Table 2A and Table 2B are estimated simultaneously in one model with including each sleep variable on the outcome side, intercepts, the effects of covariates, and random effects are presented only in Table 2B. Significant effects of interest are bolded.
AR(1) function was used to specify a first-order autoregressive variance structure, such that consecutive sleep observations are more highly correlated than non-consecutive observations.
The military hours of bedtimes were centered at midnight (0 = 00:00).
P < .10
P < .05
P < .01
p < .001.