Table 6.
Sleep and psychosocial characteristics by shift work disorder status on the Shift Work Disorder Index.
| Total Sample (n = 454) | Day Shift (n = 313) | Shift Worker without SWD (n = 79) | Shift Worker with SWD (n = 62) | F (df) | P | Part. η2 | |
|---|---|---|---|---|---|---|---|
| Mean (SD) | Mean (SD) | Mean (SD) | Mean (SD) | ||||
| Prospective Sleep Variables* | |||||||
| Sleep diary SM (time) | 4.13 (2.40) | 3.04 (1.28)a | 6.38 (3.00)b | 7.29 (2.38)b | 165.98 (2, 393) | < .001 | .458 |
| Sleep diary SE (%) | 90.92 (5.18) | 91.72 (4.75)a | 89.51 (5.79)b | 88.30 (5.44)b | 12.95 (2, 393) | < .001 | .062 |
| Sleep diary TST (m) | 431.63 (49.78) | 440.68 (43.46)a | 408.38 (51.56)b | 411.68 (63.99)b | 17.13 (2, 393) | < .001 | .080 |
| Actigraphy SM (time) | 4.16 (2.44) | 3.05 (1.30)a | 6.43 (2.57)b | 7.47 (2.46)c | 172.93 (2, 389) | < .001 | .471 |
| Actigraphy SE (%) | 86.94 (4.91) | 87.17 (4.88) | 86.61 (4.51) | 86.08 (5.50) | 1.19 (2, 389) | .305 | .006 |
| Actigraphy TST (m) | 401.78 (50.98) | 408.82 (48.10)a | 383.86 (53.49)b | 385.11 (54.94)b | 9.65 (2, 389) | < .001 | .047 |
| Retrospective Sleep/Circadian Measures | |||||||
| Insomnia (SCI) | 21.69 (7.03) | 22.62 (6.61)a | 22.43 (6.81)a | 16.03 (6.85)b | 25.80 (2, 450) | < .001 | .103 |
| PROMIS sleep-related impairment T-score* | 48.38 (8.05) | 47.2 (7.80)a | 49.02 (7.22)a | 54.57 (7.78)b | 18.27 (2, 381) | < .001 | .087 |
| Nightmares (NDI) | 2.50 (3.27) | 2.33 (3.02)a | 1.99 (3.19)a | 4.00 (4.09)b | 8.14 (2, 451) | < .001 | .035 |
| Sleep apnea risk (STOP) | 0.95 (0.81) | 0.92 (0.81) | 0.95 (0.89) | 1.13 (0.69) | 1.77 (2, 451) | .171 | .008 |
| Psychosocial Measures | |||||||
| Depression (PHQ-9) | 3.65 (3.95) | 3.05 (3.37)a | 3.49 (3.86)a | 6.88 (5.12)b | 27.29 (2, 451) | < .001 | .108 |
| Anxiety (GAD-7) | 2.79 (3.45) | 2.53 (3.26)a | 2.1 (2.89)a | 5.00 (4.18)b | 16.22 (2, 451) | < .001 | .067 |
| Posttraumatic stress (PCL-5) | 19.06 (10.55) | 17.96 (9.18)a | 16.9 (8.47)a | 27.34 (14.87)b | 24.78 (2, 450) | < .001 | .099 |
| Perceived stress (PSS) | 12.32 (6.31) | 11.64 (5.73)a | 11.43 (6.55)a | 16.89 (6.96)b | 20.45 (2, 451) | < .001 | .083 |
| Quick Drinking Screen, d/wk | 1.62 (1.65) | 1.68 (1.69) | 1.35 (1.51) | 1.58 (1.61) | 1.23 (2, 450) | .293 | .005 |
| Quick Drinking Screen, drinks per week | 2.95 (3.90) | 2.92 (3.69) | 2.91 (4.00) | 2.98 (4.66) | 0.08 (2, 450) | .992 | .000 |
a,b,cNonmatching letter pairs between columns indicate significant differences in proportions of group falling into row category based on post hoc analyses. Models presented here are unadjusted for covariates. Models were run adjusted for covariates (ethnicity, marital status) but these adjustments did not impact significance of the results; therefore, they are not reported here. *These measures were only collected on n = 400. df = degrees of freedom, GAD-7 = Generalized Anxiety Disorder Screener, NDI = Nightmare Disorder Index, PHQ-9 = Patient Health Questionnaire, PCL-5 = Posttraumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders, fifth edition, PROMIS = Patient-Reported Outcomes Measurement Information System, PSS = Perceived Stress Scale, SCI = Sleep Condition Indicator, SD = standard deviation, SE = sleep efficiency, SM = sleep midpoint, STOP = Snoring, Tired, Observed, Blood Pressure Sleep Apnea Screen, TST = total sleep time.