Wu Lora J, Gander Philippa H, van den Berg Margo, Signal T Leigh
Aerosp Med Hum Perform. 2018 Apr 1;89(4):383-388. doi: 10.3357/AMHP.4790.2018.
Many civilian aviation regulators favor evidence-based strategies that go beyond hours-of-service approaches for managing fatigue risk. Several countries now allow operations to be flown outside of flight and duty hour limitations, provided airlines demonstrate an alternative method of compliance that yields safety levels "at least equivalent to" the prescriptive regulations. Here we discuss equivalence testing in occupational fatigue risk management. We present suggested ratios/margins of practical equivalence when comparing operations inside and outside of prescriptive regulations for two common aviation safety performance indicators: total in-flight sleep duration and psychomotor vigilance task reaction speed. Suggested levels of practical equivalence, based on expertise coupled with evidence from field and laboratory studies, are ≤ 30 min in-flight sleep and ± 15% of reference response speed.
Equivalence testing is illustrated in analyses of a within-subjects field study during an out-and-back long-range trip. During both sectors of their trip, 41 pilots were monitored via actigraphy, sleep diary, and top of descent psychomotor vigilance task. Pilots were assigned to take rest breaks in a standard lie-flat bunk on one sector and in a bunk tapered 9 from hip to foot on the other sector.
Total in-flight sleep duration (134 ± 53 vs. 135 ± 55 min) and mean reaction speed at top of descent (3.94 ± 0.58 vs. 3.77 ± 0.58) were equivalent after rest in the full vs. tapered bunk.
Equivalence testing is a complimentary statistical approach to difference testing when comparing levels of fatigue and performance in occupational settings and can be applied in transportation policy decision making.Wu LJ, Gander PH, van den Berg M, Signal TL. Equivalence testing as a tool for fatigue risk management in aviation. Aerosp Med Hum Perform. 2018; 89(4):383-388.
许多民用航空监管机构倾向于采用基于证据的策略，而不仅仅局限于通过服务时长的方法来管理疲劳风险。现在有几个国家允许在超出飞行和执勤时间限制的情况下运行航班，前提是航空公司能证明有替代的合规方法，且该方法能产生“至少等同于”规定性法规的安全水平。在此，我们讨论职业疲劳风险管理中的等效性测试。在比较规定性法规内外运行情况时，针对两个常见的航空安全性能指标——飞行中总睡眠时间和心理运动警觉任务反应速度，我们给出了实际等效性的建议比率/边际值。基于专业知识以及现场和实验室研究的证据，建议的实际等效性水平为飞行中睡眠时间≤30分钟，以及参考反应速度的±15%。
在一次往返远程飞行任务的受试者内现场研究分析中展示了等效性测试。在飞行任务的两个航段中，通过活动记录仪、睡眠日记以及下降顶点心理运动警觉任务对41名飞行员进行监测。飞行员被分配在一个航段的标准平躺式床铺中休息，在另一个航段的从臀部到脚部呈9度倾斜的床铺中休息。
在全尺寸床铺与倾斜床铺中休息后，飞行中总睡眠时间（134±53分钟对135±55分钟）以及下降顶点的平均反应速度（3.94±0.58对3.77±0.58）是等效的。
在比较职业环境中的疲劳和性能水平时，等效性测试是一种与差异测试互补的统计方法，可应用于交通政策决策。
吴丽君、甘德·P·H、范登·伯格·M、西格尔·T·L。等效性测试作为航空疲劳风险管理的工具。《航空航天医学与人类表现》。2018年；89(4):383 - 388。
