With the Clinical Software Usability Survey (cSUS) reaching a key milestone recently, my thoughts have turned to the overlap between usability and safety in health IT. When I run seminars on SCCI 0129 and SCCI 0160 compliance I often pose delegates the question, “Can usability issues in health IT systems impact patient safety?”. The dilemma often splits the crowd and much debate ensues – a victory for any seminar facilitator. The discussion often goes something like this:
“If it takes me longer to do something then that takes time away from my patients.”
“Yes but if the result is that you get home later, is that really a patient safety issue?”
“If the screen looks horrible then users will lose confidence in the system.”
“Well that might affect project success but it’s not going to kill anyone.”
“What about when all the screens are cluttered with buttons and I can’t find the information I need?”
“I love screens with lots of buttons because once I know what they do I can get at everything with just one click”
So who’s right? Well for what it’s worth here’s my take on it. Usability is not one thing – Jakob Nielsen succinctly describes the components of usability as; errors, learnability, memorability, efficiency and user satisfaction. The safety debate makes much more sense when usability is examined at this level:
Errors – When a system’s design allows us (or indeed guides us) into taking actions which are erroneous then these issues are often safety-related. User interfaces should make it easy to do the right thing and either passively or actively prevent us from doing something harmful. A solid clinical risk assessment during the design phase can have overwhelming benefits on the safety profile of the user interface.
Learnability –To some extent, most systems require us to implement controls which have a human factor element. To operate software safely we need to hold a mental model of the system in our heads. The closer that mental model resembles reality the more likely we are to make the right choices. Systems which are easy to learn allow us to quickly build the correct image in our minds. System with poor learnability can introduce new hazards when they are first implemented but the risk is likely to fall to a background level once familiarity is achieved.
Memorability – If we know how to operate a system safely today but by tomorrow we have forgotten then our human factor controls quickly become ineffective. Busy clinicians can (and will) only remember so much. Workarounds which require a hard-to-remember sequence of actions disparate to the primary workflow will fail to actively mitigate risk in the long term.
Efficiency – The ability of a system to facilitate us meeting our objectives in a timely manner is perhaps the most controversial when it comes to patient safety. We increasingly expect systems to respond instantaneously and even a 2-3 second delay can feel like an age when watching an egg-timer. It’s true that those few seconds can add up over the course of a day but an argument for improved performance is often best made on grounds of system appeal and the meeting of Service Level Agreements. Sometimes it is best to reserve the safety angle for those issues which directly impact care. That said, when the safe workflow takes considerably longer than an unsafe workflow a stronger argument can be formulated.
Satisfaction – Some systems have that enigmatic characteristic of aesthetic appeal whilst others are less than handsome. In a crowded marketplace it is often these qualities that differentiate one application from another and it’s an important consideration for any designer. But of all the facets of usability it is this one which impacts the least on patient safety. At times we might feel that an ugly interface is unappealing and perhaps use a safety argument to effect change. This can however undermine an objective assessment of clinical risk and spread the wrong message about what patient safety represents.
Do health IT usability issues affect patient safety? In many ways, it’s simply the wrong question. Instead think, “Can I describe a credible and realistic story that would typically lead to patient harm in the everyday clinical environment?” If not, your usability issue might still be a perfectly valid concern but benefit from an argument based on user uptake, project success or reputation rather than patient safety.