During the development of medical devices or medication delivery equipment, the machine eventually meets a human being. We can imagine if a product feels good in your hands, it will be easier to wield by different users or in unexpected situations. Articulating the human-machine interface and its nuances lies at the heart of medical human factors engineering.
Perception Is Reality
In order to improve device safety, the FDA published new guidelines (June 2011) regarding human factors, and validation has become significantly more rigorous. Many times a gap exists between how developers see their device compared to the end user experience. For instance, you might think that the trigger on your device is adequate, but surgeons might consider it a nuisance.
Physical and cognitive obstacles often translate into risk to the user or the patient. In considering those issues, the FDA subsequently tightened requirements.
The most complete assessments should take into account:
- User characteristics – Who’s your user? What are their skills and limitations?
- Intended use – What it’s for and why.
- Environmental aspects – Will the device be used in the OR, ER, or ICU? Or at the patient’s home?
- Device-user interface – Dials, buttons, knobs, screens, triggers, etc.
- History of previous problems – Identifying what didn’t work well in the past helps improve future results.
Simulated testing is one way human factors engineering seeks to tease out potential device problems. A qualified field of actual end users can vet and validate products unlike any other test scenario.
Human factors simulation includes evaluating unanticipated situations that could come up in the field, such as distractions, noise, or poor visibility. What if the surgeon is tired while using the device? Or will prolonged use cause hand or finger cramping? Simulations help answer these questions in the validation phase allowing for error detection well before the product hits the market.
It’s essential that the testing team represent actual potential end users of the product. These could be physicians, nurses, scrub techs, or even patients. In some cases, a complete bioskills lab might be required including access to cadaver specimens for advanced interventional or surgical devices.
Device companies often cringe at the thought of validation processes as just another hurdle to the production phase. However, it’s best to consider the rich opportunity available in this part of due diligence. Real user feedback remains essential to any product development, and the detection of significant errors could prevent catastrophic future losses. The end result is shortening time to market for a truly viable, valuable, and safe product.
Tying It All Together
During and after the human factors validation, the process provides valuable data that assists in fine tuning how your device will be used – which might not be exactly what you expected in the development stage. Take full advantage of this process to satisfy regulations and bring your product to market faster.