Table 3.
Descriptive Statistics and Between-Group Comparisons Using Independent Samples T Tests on Four Facets of Sleep
| 1. Control(n=33) | 2. mTBI(n=33) | 3. CMC(n=33) | 1 vs 2 | 2 vs 3 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Measure | M (SD) | M (SD) | M (SD) | t (df) | 95% CI | p | d | t (df) | 95% CI | p | d |
| Sleep quality | |||||||||||
| PROMIS8b (disturbance) | 20.01 (5.84) | 25.49 (5.72) | 21.26 (7.55) | −3.85 (64) | [−8.32, −2.63] | <.001 | .96 | −2.57 (59.59) | [−7.53, −0.94]- | .007 | −64 |
| STQ SOLa | 25.06 (17.09) | 25.97 (15.68) | 23.93 (18.52) | −0.45 (61) | [−9.16, 7.35] | .414 | .05 | −.46 (59) | [−10.85, 6.78] | .323 | −.12 |
| STQ WASOa | 12.81 (18.56) | 23.35 (24.23) | 12.1 (17.13) | −1.94 (61) | [−21.39, 0.31] | .029 | .50 | −2.09 (59) | [−22.00, −0.51] | .021 | −.54 |
| ISIa | 13.42 (4.60) | 17.53 (5.27) | 15.09 (5.59) | −3.35 (63) | [−6.56, −1.66] | <.001 | .84 | −1.81 (63) | [−5.13, 0.25] | .038 | −.46 |
| STQ Sleep Efficiency M% (SD) | 92.14 (5.88) | 89.59 (8.89) | 92.45 (6.47) | 1.30 (57) | [−.01, .06] | .100 | −.34 | 1.42 (57) | [−1.18, 6.91] | .081 | .37 |
| Sleep quantity | |||||||||||
| STQ sleep duration: Mhours (SD)b | 7:56 (60 min) | 7:32 (84 min) | 7:48 (79 min) | 1.28 (57) | [−0:13, 1:02] | .104 | −.34 | .75 (57) | [−0:26, 0:58] | .229 | .20 |
| Sleep timing | |||||||||||
| STQ usual bedtime MTime (SD)a,c | 23:01 (74 mins) | 22:54 (70 mins) | 23:25(84 mins) | 0.36 (58) | [−0:30, 0:44] | .725 | .09 | 1.54 (58) | [−9:32, 1:11] | .065 | .40 |
| STQ usual waketime MTime (SD)a,c | 07:40 (72 mins) | 07:16 (76 mins) | 07:50(82 mins) | 1.21 (57) | [−0:15, 0:61] | .233 | −0.32 | 1.62 (57) | [−8:07, 1:15] | .056 | .43 |
| STQ sleep midpoint MTime(SD)a,c | 03:20 (69 mins) | 03:05 (65 mins) | 03:38(76mins) | 0.81 (57) | [−0:20, 0:49] | .422 | .21 | 1.75 (57) | [−4:50, 1:09] | .043 | .46 |
| Sleep-related daytime impairment | |||||||||||
| PROMIS8a (impairment)a | 19.80 (7.68) | 23.64 (6.22) | 20.27 (7.00) | −2.21 (63) | [−7.31, 0.37] | .016 | .56 | −2.05 (63) | [−6.64, −0.08] | .023 | .52 |
| Epworth Sleepiness Scale | 14.12 (4.50) | 14.69 (4.82) | 14.24 (3.06) | −.490 (63) | [−2.88, 1.74] | .313 | .12 | −.45 (52.68) | [−2.49, 1.58] | .330 | .11 |
N=69.
SD, standard deviation; mTBI, mild traumatic brain injury; CMC, close-matched control; CI, confidence interval of the mean difference; d, Cohen's d for independent samples; PROMIS8b (disturbance)=Patient-Reported Outcomes Information System Sleep Disturbance Version 1.0 Short Form; STQ, Sleep Timing Questionnaire; SOL, sleep onset latency (from the STQ); WASO, wake after sleep onset (from the STQ); ISI, Insomnia Severity Index; PROMIS8a (impairment)=Patient-Reported Outcomes Information System Sleep-Related Impairment Version 1.0 Short Form.
Nonparametric Mann-Whitney U tests were conducted for these variables; however, the results did not change. Therefore, the t test that is reported here is for consistency.
Mean hours and minutes sleeping (e.g., 7:56=7 h and 56 min).
Clock hour, in hours and minutes.