Human Factors Validation

Doctors utilizing medical devices

Human Factors Validation

The Human Factors/Usability Engineering process culminates with the execution and reporting of a Human Factors Validation study. Formative Testing precedes Human Factors Validation and provides an early assessment of risk and use-related risk mitigations. Following a successful Formative study, the Human Factors Validation study is then conducted to formally confirm the user interface can be used in a safe and effective manner by the intended users, and for its intended uses. Additionally, the final report should include a discussion of the product benefits relative to residual risks.

Learn more about Human Factors Validation and how Improvita can guide you through the process.

What are the Key Considerations in a Well-Designed Human Factors Validation Testing?

There are three phases in conduct of Human Factors Validation Testing: Study Preparation, Study Execution, and Study Reporting.


Study Preparation

In the study preparation phase, the intended users, use scenarios, and use environment are researched and identified to develop an in-depth understanding of how the users interact with the product.

Once the intended users, uses, and use environments are defined, the Human Factors risk management process can be initiated. A task analysis should be utilized to identify how the user will interact with the product, including their perception of the steps, their thought process, and how they will physically engage with the design.

Task analysis creates a foreseeable sequence of events, which can identify what is known as a hazardous situation. A hazardous situation according to the FDA is a circumstance in which people, property, or the environment is/are exposed to one or more hazard(s).

The hazardous situation will drive the risk management process to identify the hazard the user may be exposed to, which is the potential source of harm. According to the FDA, harm is defined as injury or damage to the health of people, or damage to property or the environment. There are varying degrees of severity of harm, and the severity must be determined by a medical professional.

The resulting severity of harm will drive identification of task criticality. A critical task is defined by the FDA to be a task which, if performed incorrectly or not performed at all, would or could cause serious harm to the patient or user, where harm is defined to include compromised medical care. The severity of the harm, in conjunction with an estimated probability of occurrence the hazardous situation is to occur (often determined by a medical professional and the results from a known use errors analysis), results in determination of use-related risk.

As the Human Factors Validation study protocol is prepared, any previous Human Factors inputs are reviewed. This includes the review of Formative Evaluations conducted earlier in the Human Factors/Usability Engineering process which may explore the user interface design strengths, weaknesses, and unanticipated use errors. The results of the Formative Evaluation are incorporated into Human Factors risk management deliverables to finalize critical task determination before the Human Factors Validation Protocol is finalized.

Once the risk management documents have been updated following the Formative Evaluations and task criticality has been determined, all necessary inputs are in line to finalize the test protocol. These items have a significant impact on content such as task sequencing, success criteria, participant eligibility criteria, and moderator questions. As a best practice, the finalized protocol should be submitted for review by the FDA to gain concurrence on the test population and the protocol.


Study Execution

Recruitment of study participants who have the defined intended user attributes is central to the success of the study. To secure the full complement of users it helps to have a strong recruitment team who understands the unique population and their needs.

During study execution, the participant’s response and task performance is carefully monitored by a moderator. A trained observer from the study team may also act as a data collector. Once the tasks and scenarios have been completed, the moderator and/or observer may ask the participant questions about their interactions with the product, their knowledge of the important information about use of the product, or general feedback on the product.

Upon completion of the Human Factors Validation study, all study data, including performance against acceptance criteria (use errors, close calls, and difficulties), is subject to a robust root cause analysis. These results, together with supporting statistics, are summarized in the Human Factors Validation report.


Study Reporting

Study reporting requirements vary slightly based on criticality of the medical device, and between medical devices and combination products. Generally, reporting a Human Factors Validation study should follow the FDA draft guidance Content of Human Factors Information in Medical Device Marketing Submissions:

  • Section 1: Conclusion and High-Level Summary
    • This section should include a statement indicating whether “the user interface of the device has been found to be adequately designed for the intended users, uses, and use environments, and whether new Human Factors testing was conducted to support this conclusion” (FDA Draft Guidance).
    • This section should also contain information on any residual risk that remains after the control measures have been implemented.
  • Section 2: Descriptions of Intended Device Users, Uses, Use Environments, and Training
    • This section should include: a description of the intended user population, a summary of the product’s intended use, a summary of the product’s operational context of use and critical aspects of product operation, a summary of the intended use environments, and a description of any training users should receive.
    • It is important to note that in this section, a ‘use environment’ is identified as actual conditions and setting(s) in which users would interact with the product.
  • Section 3: Description of Device-User Interface
    • This section should include: a graphical representation of the product and the user interface, a written description of the user interface, a copy of the labeling that will be provided to the user with the product, and an overview of the operational sequence of the product and the user’s expected interactions with it.
  • Section 4: Summary of Known Use Problems
    • The Known Use Problems analysis should be conducted prior to study execution. A review of the known use problems and mitigations in place should be included in the report.
  • Section 5: Summary of Preliminary Analyses and Evaluations
    • This section should include information on any previous Human Factors studies and a summary of those activities, including results and design modifications in response to those results.
  • Section 6: Analysis of Hazards and Risks Associated with the Device
    • This section should include details of the risk management processes that were conducted prior to execution, as well as a discussion on any new hazards or harms that are identified. If it is determined that a product change resulting in a modification to any task, harm, or mitigation does not merit new Human Factors testing, a rationale should be provided in this section.
  • Section 7: Identification and Description of Critical Tasks
    • This section should include the processes used to identify critical tasks, as well as a listing of all tasks and their established criticality. This list should also identify the scenarios under which each task, critical and non-critical, are categorized.
  • Section 8: Details of Human Factors Validation Testing of Final Design
    • This section should include a summary of all validation activities, design modifications in response to test results, and a discussion on the benefit-risk analysis. In this section, submitters should also evaluate the mitigations in place to confirm that risks are reduced to as low as reasonably possible, and, if necessary, identify other means to reduce risk.

Why Choose Improvita for Human Factors Validation?

At Improvita, our team of experts brings extensive experience in Human Factors Validation Testing, guiding you through every step of the process. We are committed to complying with regulatory requirements and our focus is on user-centered design. We will help you minimize risk and enhance the overall user experience, ultimately leading to safer and more successful products.

To learn more about Improvita’s Human Factors Validation consulting services, contact us to discuss your specific needs