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

ABSTRACT 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. 394 investigations were analyzed and 12% of them were 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 to injure 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 fatigued-related accidents, and 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.