Effects of partial sleep deprivation: speed management ability and associated crash risk

Abstract

ABSTRACT This study modelled the effects of partial sleep deprivation (PSD) in terms of sleep debt on mean speed, speed variability and associated crash probability. Fifty male drivers drove the driving simulator in three test sessions (TS): TS1 (night) and TS2 (lunch) after one and two consecutive nights of PSD (sleep ≤4.5h; measured using Actiwatch), respectively and TS3 with no sleep deprivation. The mean sleep debt observed in TS1, TS2 and TS3 were 2.2 h, 1.53 h and no sleep debt, respectively. A generalized linear mixed model (GLMM) model results showed that the crash risk increased 1.5 times with increasing sleep debt, 27% with increasing speed and doubled with increasing speed-variability. The findings show that reducing speed by more than 15% could have eliminated the risk of crashes. However, the drivers suffered from loss of speed control under the sleep debt conditions.