Tragic Design

There’s a concept used in the healthcare field called the Swiss Cheese model of accident causation. This model (see Figure 1-2) compares human systems to multiple slices of holed cheese. There may be multiple layers to pass through before a mistake affects the patient. For example, when there is a medication error, the source of the error can occur in any of these “layers”: the doctor’s prescription, the pharmacist filling it, the medication being stocked correctly, the nurse preparing and giving it, and the mechanism used to administer it to the patient. Each layer has its own holes (flaws in the preventative measures), but together they reduce the chances of an error happening. In our example, nurses were the last layer of defense, so it’s easy to blame them for the mistake that happened. But in fact, interface design should act as the last layer in that model. It usually accomplishes that by reducing the cognitive load required to complete a task, thus allowing more resources to be dedicated to error prevention. Unfortunately, in the healthcare industry, it instead leads to making more holes.