Human Factors Take Center Stage in FDA Guidance Documents

In the February 3, 2016 Federal Regis­ter, the FDA issued three guidance docu­ments on human factors engineering (one final and two draft documents). These are relevant to clinical research as medical de­vice manufacturers conduct clinical trials to evaluate human use factors during their device development programs. Human factors/usability engineering consider­ations in the development of medical de­vices involve the three major components of the device-user system: (1) device users, (2) device use environments and (3) device user interfaces.

The intended users of a medical device should be able to use the device without making errors that could compromise medical care or patient or user safety. De­vice users may be clinical caregivers, other hospital workers (radiology or laboratory technologists), therapists, home care aides or the professionals who install and set up the devices and those who clean, maintain, repair or reprocess them. Intended users also may be the patients themselves, or a family member or friend who serves as a lay caregiver. The environments in which medical devices are used include a variety of conditions that would drive the user in­terface design. Medical devices are used in clinical or non-clinical environments, community settings or moving vehicles. A device user interface includes all points of interaction between the user and the de­vice, including all elements of the device with which the user interacts. A device user interface might be used while the user sets up the device, uses the device or per­forms maintenance on the device.

The FDA writes that the critical element is the device user interface. Human factors/usability engineering is used to design the user-device interface. The user interface includes all components with which users interact while preparing the device for use (e.g., unpacking, set up, calibration), using the device, or performing maintenance (e.g., cleaning, replacing a battery, mak­ing repairs). The most important goal of the human factors/usability engineering process is to minimize use-related hazards and risks and then confirm that these ef­forts were successful and users can use the device safely and effectively. Specific bene­ficial outcomes of applying human factors/usability engineering to medical devices include:

• Easier-to-use devices.
• Safer connections between device com­ponents and accessories (e.g., power cords, leads, tubing, cartridges).
• Easier-to-read controls and displays.
• Better user understanding of the de­vice’s status and operation.
• Better understanding of the patient’s current medical condition.
• More effective alarm signals.
• Easier device maintenance and repair.
• Reduced user reliance on user manuals.
• Reducing need for user training and retraining.
• Reduced risk of use error, adverse events and product recalls.

From a clinical trial perspective, human factors testing usually means simulated-use testing, where likely users operate the device in a controlled setting in order to ensure that problems related to use of that device can be recognized and then eliminated or least substantially mitigated through further development efforts.

The Guidance Documents

Under Docket No. FDA-2011-D-0469, the FDA made available a final guidance document titled, “Applying Human Fac­tors and Usability Engineering to Medi­cal Devices.” This guidance document is intended to assist industry in following appropriate human factors and usabil­ity engineering processes to maximize the likelihood that new medical devices will be safe and effective for the intended us­ers, uses, and use environments. The rec­ommendations in this guidance document are intended to support manufacturers in improving the design of medical devices to minimize potential use errors and result­ing harm. The FDA believes that these rec­ommendations will enable manufacturers to assess and reduce risks associated with medical device use.

For safety-critical technologies such as medical devices, the process of eliminat­ing or reducing design-related use prob­lems that contribute to or cause unsafe or ineffective medical treatment is part of a process for controlling overall risk. For devices where harm could result from “use errors,” the dynamics of user interaction should be included in risk analysis and risk management. By incorporating these considerations into the device develop­ment process, manufacturers can reduce the overall risk level posed by their devices, thus decreasing adverse events associated with the device and avoiding potential de­vice recalls.

The June 22, 2011, the draft version of this guidance netted more than 600 com­ments, which were generally supportive of the draft guidance document, but re­quested clarification in a number of areas.

The most frequent types of comments re­quested revisions to the language or struc­ture of the document, or clarification on risk mitigation and human factors test­ing methods, user populations for testing, training of test participants, determining the appropriate sample size in human fac­tors testing, reporting of testing results in premarket submissions, and collecting hu­man factors data as part of a clinical study.

Under Docket No. FDA-2015-D-4599, the FDA made available the draft guidance doc­ument titled, “List of Highest Priority De­vices for Human Factors Review.” They are:

• Ablation generators (associated with ablation systems).
• Anesthesia machines.
• Artificial pancreas systems.
• Certain auto injectors.
• Automated external defibrillators.
• Certain duodenoscopes.
• Certain gastroenterology-urology endo­scopic ultrasound systems.
• Hemodialysis and peritoneal dialysis systems.
• Infusion pumps (implanted or other­wise).
• Insulin delivery systems.
• Negative-pressure wound therapy intended for use in the home.
• Robotic catheter manipulation systems and surgery devices.
• Ventilators.
• Ventricular assist devices.

The FDA stated that these device types should have human factors data included in premarket submissions. They have clear potential for serious harm resulting from use error and having human factors data will help the FDA evaluate the safety and effectiveness and substantial equivalence of these devices. Currently, this is a draft guidance and therefore is not intended to be implemented but once the guidance is made final, the FDA will suggest that for the listed devices, manufacturers should provide the FDA with a report that pro­vides a summary of the human factors or usability engineering processes they have followed, including any preliminary anal­yses and evaluations and human factors validation testing, results and conclusions.

Alternatively, manufacturers may pro­vide a detailed rationale supporting the conclusion that human factors data are not necessary. This would be based on analysis of risk associated with users, uses, and use environments and results of that analysis would indicate that the severity of the po­tential harm resulting from use error is not serious. Further, for device types not on the list, the FDA will expect to see human factors data if analysis of risk indicates that users performing tasks incorrectly or fail­ing to perform tasks could result in serious harm. The FDA may also decide that hu­man factors data are needed on a case-by-case basis. In other words, this list is just a starting point.

Under Docket No. FDA-2015-D-4848, the FDA also made available a draft guid­ance document titled “Human Factors Studies and Related Clinical Study Con­siderations in Combination Product De­sign and Development.” This document provides guidance to industry and the FDA staff on the underlying principles of human factors (HF) studies during the development of combination products, which are comprised of any combination of a drug and a device; a device and a bio­logical product; a biological product and a drug; or a drug, a device, and a biological product. It describes the FDA recommen­dations on HF information to be provided in a combination product investigational or marketing application. It clarifies the different types of HF studies, offers recom­mendations for timing and sequencing of HF studies, and discusses how HF studies contribute to ensuring that combination products are safe and effective for the in­tended users, uses and environments. In addition, the draft guidance describes how HF studies relate to other clinical studies.

Interested parties may submit com­ments on final guidance documents at any time. The FDA may consider those com­ments for future revisions. For the draft guidance documents, to ensure that the FDA considers those comments before it begins work on the final versions, submit comments on the draft documents by May 3, 2016. Submit electronic comments at http://www.regulations.gov/. Submit writ­ten comments to the Division of Dockets Management (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Room 1061, Rockville, MD 20852. FDA has in­structions on how to submit confidential information. If those instructions are not followed, any submitted confidential in­formation will be made public.

The Regulatory Update is excerpted from Research Practitioner, Volume 17, Number 02, Mar.-Apr. 2016.