On April 23, 2010 the FDA's Center for Devices and Radiological Health(CDRH) issued a draft guidance for manufacturers of drug delivery pumps regarding new requirements for pre-market submissions. The Office of Device Evaluation (ODE) is the point of review for pre-market submissions, including human factors reviews. The guidance emphasizes the requirement for evidence of use-related hazard management through user interface testing. Interface design hs been a major contributor to adverse events over the past decade including recalls. The guidance calls for two types of human factors testing: (1) simulated use validation studies , and (2) clinical evaluations of the user interface. The design for these evaluations is not stated in the guidance, but will be a major topic in pre-IDE ODE meetings with maufacturers. This represents a huge opportunity for the human factors community to apply field research skills honed in aviation, military, nuclear power, and transportation system domains. The guidance may be accessed at the CDRH website.

AAMI's Human Factors for Medical Devices course was offered in April 19-21 in Arlington, VA with another good group of 45 participants from industry. The highlights of the workshop included a final exercise for participant groups involving the design of a human factors validation study with a follow up critique by Ron Kaye, FDA/CDRH/ODE Human Factors Team Leader and by the course faculty. This exercise explored the successful elements of designing the study and the FDA expectations for sample size, user population, task choice, and observed failures and unexpected outcomes. Other course highlights included discussion of the new Human Factors medical device standard, HE-75 which had just been released by AAMI March 30. Upcoming workshops will be held in Minneapolis in October (see AAMI website) and an in-house version of the course for the FDA CDRH Staff College this fall in the Washington DC area. This workshop will be a critical oppportunity to inform reviewers and inspectors about the main aspects of human factors and its relationship to risk management.

The Validation Study, resulting from an interative process of error removal in design, is the key deliverable

The device clearance process, centered in the Office of Device Evaluation of FDA/CDRH, focuses on the manufacturer's proof of the "safety and effacacy of the device." Traditionally, this has required due diligence and submission of testing results for component reliability, software and hardware fail-safe capability, manufacturing process quality, and evidence of proof of clinical claims of the device. Risk management concerning user interactions with the device has been a concern, but not systematically evaluated on a daily basis by ODE reviewers. That all changed when CDRH moved several human factors scientists to the Office of Device Evaluation in 2008.

What's Different Now About Human Factors at FDA?

The FDA had always stressed the importance of employing human factors techniques in understanding and controlling use error risks in medical device design and development. So what's different now?

Human factors reviewers have become part of the overall review team and process at ODE. This means they now are looking at many more submissions for evidence of validation that use errors have been systematically removed from the user interfaces of medical devices. Members of the human factors group are now given "consults", that is, a voice at the table determining whether a submission is adequate for clearance, especially where the user interface and device interaction is critical to safety.

What are they looking for?

The major piece of evidence that human factors reviewers need for assurance that use related hazards have been removed is a carefully designed and executed validation study with participants from the appropriate user populations.