Objective vs perceived sleep in Belgian occupational drivers: A field study

This prospective, descriptive observational study aimed to investigate objective and subjective sleep among Belgian occupational drivers, focusing on short haul (SHD), long haul (LHD), and local delivery drivers (LDD).

A total of 31 drivers wore a Fitbit Charge 5 for one month to capture total sleep time (TST), time in bed (TIB), sleep efficiency (SE), wakefulness and sleep stage distribution. Subjective sleep was assessed daily using a 5-point scale. Data were analyzed using descriptive statistics, one-way ANOVAs and Pearson correlations.

Drivers averaged 6.2 ± 0.7 h of TST and 7.1 ± 0.7 h of TIB, with a mean SE of 87.3 ± 2.1 %. Sleep stages were distributed as follows: 60.1 ± 5.2 % light sleep (LS), 18.0 ± 3.3 % deep sleep (DS), 21.2 ± 4.2 % REM sleep and 12.8 ± 1.8 % of awake. 12.9 % of participants had low DS (<15 %) and 25.8 % had low REM (<20 %). 29.0 % of participants experienced elevated nocturnal wakefulness. One-way ANOVA revealed no significant group differences in most sleep parameters, except for DS (F = 3.47, p = 0.05), with LHD showing the lowest proportion. Subjectively, most drivers rated their sleep from good to neutral. However, one-third reported poor sleep. Modest correlations were found between better subjective sleep and higher DS, TST, and SE.

Although SE was adequate, chronic sleep restriction was common. Group differences were minimal, suggesting that individual and environmental factors may outweigh driver type in influencing sleep. Subjective assessments only partially aligned with objective measures, reflecting a discrepancy between perceived and objective sleep.