Fatigue in NTSB investigations 2013-2019: evidence of accidents and injuries

This study updates the prevalence of operator fatigue as a causative factor in accidents investigated by the National Transportation Safety Board (NTSB) and the associated injury severity in fatigue-related accidents. In total, 394 investigations were analyzed and 12% of them identified fatigue. The prevalence of fatigue varied among the transportation modes, ranging from 28% of aviation to 7% of marine. Most fatigue-related accidents (48%) occurred during late night or morning. Compared to non-fatigued operators, fatigued operators were more involved in severe or fatal injuries (odds ratio [OR] 2.30; 95% confidence interval [CI] [1.66, 2.95]) and injuries to non-operators (OR 3.32; 95% CI [2.70, 3.95]). Obstructive sleep apnea (OSA) was identified as a probable cause, contributing cause or finding in 15% of fatigue-related accidents, and in 85.7% of these accidents the operator met OSA screening criteria. Thus, opportunities remain for preventing fatigue-related accidents, including through more systematic operator screening for OSA.