TABLE 2

Sleep latency, sleep duration and Pittsburgh Sleep Quality Index (PSQI) component score data obtained from PSQI questionnaire

VariablePoor sleep quality (PSQI>5)Good sleep quality (PSQI≤5)p-value
Sleep latency min30 (15–45)10 (5–15)<0.0001
Sleep duration h6 (5–7)8 (7–9)<0.0001
PSQI global score au9.8±2.93.5±1.2
PSQI component scores#
 Sleep quality1.43±0.660.68±0.64<0.0001
 Sleep latency1.77±0.900.44±0.61<0.0001
 Sleep duration1.25±1.050.12±0.41<0.0001
 Habitual sleep efficiency1.68±1.090.15±0.36<0.0001
 Sleep disturbance1.97±0.691.38±0.55<0.0001
 Use of sleep medications0.62±1.140.03±0.170.004
 Daytime dysfunction1.25±0.790.71±0.720.001

Data are presented as mean±sd or median (interquartile range), unless stated otherwise. au: arbitrary units. #: Each component score ranges from 0 (no difficulty) to 3 (severe difficulty) on a Likert scale.