Human Error Models

Human error has been extensively studied and a great deal is known about contributing factors and causes. However, the absolute prediction and elimination of human error is elusive and will probably always remain so. What is known can be applied to reduce human error or, at the very least, to reduce its consequences.

There are several approaches to human error:

• Person model - This is the traditional approach to human error that "names, blames, and shames" an individual(s) as "causing" the accident. The underlying assumption is that mistakes and errors are the result of negligence, inattention, carelessness, lack of skill or knowledge, lack or motivation or one of a host of other faulty, negative mental processes. This model uses fear and discipline to attempt to improve safety. The person model considers errors as a "moral" issue that "bad things happen to bad people."*
• System model - This model recognizes that there are systemic contributions to and causes of error. It acknowledges that the organizational culture, human-to-system interface design, and environmental elements can create "latent failure" conditions. These latent failure conditions contribute to human error. The system model recognizes human limitations and that human error is inevitable. Therefore, systems should be designed to anticipate human error and to mitigate its consequences.*

*Reason, J, "Human error: models and management," BMJ 2000; 320:768-770