Delta: The Value That Matters in Fatigue Risk Management.

ABSTRACT

INTRODUCTION: Noninferiority or equivalence testing are often used when comparing a novel pharmaceutical, operation, or procedure to the current standard designated as safe. Noninferiority and equivalence testing require estimates of a metric called delta the margin of meaningful difference. Inappropriate delta margins can lead to invalid conclusions, thereby creating uncertainty about a studys scientific credibility. We recommend that a working group be convened with the following goals 1) to evaluate delta values currently in use in aviation; 2) to determine if it is possible to develop a systematic, evidence-based, and replicable process to derive delta values based on statistical properties from population data, rather than a mixture of evidence- and opinion-based processes; and 3) based on the findings of the second goal, update the current delta values in use in aviation. This working group should include, at a minimum, government agencies and other key stakeholders using these values within operational settings.Lamp ACM, Rempe MJ, Belenky GL. Delta the value that matters in fatigue risk management. Aerosp Med Hum Perform. 2021; 92(2)127128.