Skip to main content

Table 4 Comparison of sleep parameters between SWSD, No SWSD and non-shift Groups

From: Prevalence, predictors and effects of shift work sleep disorder among nurses in a Nigerian teaching hospital

Variables Shift group Non-shift group p1 p2 p3
SWSD
n = 19
No SWSD
n = 25
n = 44
Nocturnal sleep durationa (Mean ± SD) 5.8 ± 1.4 5.9 ± 1.1 7.2 ± 1.3 0.922 < 0.001 < 0.001
 • < 7 h n (%) 11 (57.9) 15 (60.0) 16 (36.4) 0.888 0.113 0.058
 • 7–9 h n (%) 8 (42.1) 10 (40.0) 28 (63.6)
Daytime sleep durationa (Mean ± SD) 2.7 ± 0.8 2.4 ± 0.6 1.0 ± 0.6 0.672 < 0.001 < 0.001
Sleep efficiencya(Mean ± SD) 75.9 ± 11.7 85.9 ± 9.2 86.3 ± 10.6 0.002 0.001 0.893
ESS score (Mean ± SD) 12.6 ± 2.8 5.3 ± 2.7 6.1 ± 3.8 < 0.001 < 0.001 0.356
 • EDS n (%) 17 (89.5) 0 (0) 7 (15.9) < 0.001 F < 0.001 F < 0.001 Y
 • No EDS (%) 2 (10.5) 25 (100.0) 37 (84.1)
ISI score (Mean ± SD) 8.4 ± 3.6 6.6 ± 2.3 5.8 ± 2.5 0.207 0.028 0.453
 • Insomnia n (%) 2 (10.5) 0 (0) 0 (0) 0.181F 0.088F
 • No insomnian (%) 17 (89.5) 25 (100.0) 44 (100.0)
  1. P1 SWSD vs No SWSD groups; p2 SWSD vs non-shift Groups; p3 No SWSD vs non-shift Groups
  2. SWSD Shift Work Sleep Disorder, ESS Epworth Sleepiness Scale, EDS Excessive daytime sleepiness, ISI Insomnia Severity Index
  3. aAverage of nocturnal sleep duration over 30 days
  4. FFisher’s exact
  5. YYates corrected
  6. Bold enteries are statistically significant