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. 2015 Jul 27;65(637):e508–e515. doi: 10.3399/bjgp15X686137

Table 3.

Sleep results for simplified sleep restriction versus control at baseline and 6 months. Data presented as mean (SD)

Intervention (Simplified sleep restriction) Control Difference between the groups,b,d (95% CI) P-value


Baseline scorean= 46 6-month scorean= 43 Mean change (95% CI)b,c Baseline scorean= 51 6-month scorean= 50 Mean change (95% CI)b,c
Primary outcomes

Sleep efficiency % (sleep diary) 73.32 (11.80) 80.46 (10.66)e 6.72 (3.90 to 9.54) 74.15 (11.05) 78.24 (10.52)f 4.28 (−6.70 to 1.86) 2.44 (−0.96 to 5.84) 0.200

Sleep efficiency % (actigraphy) 82.68 (4.66) 83.74 (4.94)g 1.75 (0.42 to 3.09) 82.37 (4.67) 81.96 (5.38)f −0.46 (−1.58 to 0.65) 2.22 (0.65 to 3.79) 0.006

Secondary outcomes

Epworth Sleepiness Scale 5.17 (3.70) 3.70 (2.93) −1.62 (−2.72 to −0.53) 6.45 (3.29) 4.86 (3.28) −1.55 (−2.50 to −0.61) −0.07 (−1.40 to 1.27) 0.900

Flinders Fatigue Scale 12.74 (6.83) 7.30 (5.49) −5.39 (−7.16 to −3.63) 12.53 (5.11) 9.08 (4.96) −3.12 (−4.65 to −1.59) −2.27 (−4.42 to −0.13) 0.040

Sleep onset latency, minutes
  Sleep diary 31.50 (23.00) 22.77 (19.60) −6.29 (−12.75 to 0.16) 29.55 (22.48) 25.21 (19.38)e −2.84 (−8.38 to 2.70) −3.45 (−11.23 to 4.32) 0.400
  Actigraphy 16.10 (14.47) 13.37(7.91)f −5.08 (−9.90 to −0.26) 14.66 (12.42) 15.61 (12.74)e 1.06 (−2.97 to 5.08) −6.13 (−11.82 to −0.44) 0.040

Wake after sleep onset, minutes
  Sleep diary 44.82 (28.92) 29.47 (31.71) −13.37 (−22.69 to −4.05) 47.84 (30.14) 40.02 (27.00)e −7.61 (−15.60 to 0.39) −5.76 (−17.00 to 5.47) 0.300
  Actigraphy 47.59 (13.88) 44.33 (15.44)f −4.54 (−8.99 to −0.08) 51.81(19.51) 51.59 (17.50)e −1.46 (−5.18 to 2.27) −3.08 (−8.35 to 2.18) 0.200

Total sleep time, minutes
  Sleep diary 369.59 (65.27) 397.30 (63.29) 23.71 (9.51 to 37.90) 376.93 (61.08) 398.17 (64.91)e 18.99 (6.81 to 31.67) 4.72 (−12.39 to 21.83) 0.600
  Actigraphy 415.68 (34.17) 407.20 (36.92)f −7.00 (−15.94 to 1.95) 418.36 (39.36) 415.05 (38.45)e −7.10 (−14.58 to 0.38) 0.10 (−10.47 to 10.67) 0.990

Statistically significant results are in bold.

a

Observed (raw) data.

b

Multiple linear regression adjusted for age, sex, and baseline insomnia severity (using Insomnia Severity Index score26).

c

Least square mean for change from baseline to 6-month score.

d

Least square mean difference for change from baseline to 6-month score between sleep restriction and control group.

e

n = 43.

f

n = 49.

g

n = 42.