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Update: Check First with FDA Regarding Their Current Availability to Review a Human Factors Validation Test Protocol

Recommendations for manufacturers seeking test protocol reviews as FDA deals with 510(k) backlogs

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August 6, 2021

Updated on August 12, 2021

In recent years, the US Food and Drug Administration has strongly encouraged medical device manufacturers to submit human factors (HF) validation test protocols for agency review prior to testing. Paraphrasing, FDA’s message to industry is to let the agency check the manufacturer’s protocol before the test commences to assess whether (1) the test method aligns with the agency’s expectations, and (2) data is being collected and analyzed in a sufficiently rigorous manner.

However, the reallocation of resources in response to the COVID-19 pandemic has reduced the agency’s capacity to conduct some HF validation protocol reviews. Consequently, the agency has had to turn down some companies seeking such reviews, or may need more time than usual to complete them.  

Recommendations for HF validation test protocol developers

So, if you’re a medical device manufacturer preparing for a human factors validation test and you hoped to receive FDA feedback on your protocol, we advise the following approach:

  • Be sure your regulatory specialists have reviewed FDA’s official guidance regarding modifications to the pre-submission process during the COVID-19 crisis.
  • Ask the FDA if they can review a forthcoming HF validation test protocol. Take this action well ahead of when you plan to submit the protocol for review.
  • Do not submit a synopsis or other high-level description of your HF validation protocol. Assume that only fully-developed protocols submitted with the appropriate background information (e.g., draft content from Sections 2-7 of the HFE/UE report) will be accepted for review.
  • If the FDA can commit to a review, submit your protocol in the usual manner.
  • If the FDA cannot commit to a review, you might still choose to submit the protocol in case capacity for reviews increases. In parallel, plan to conduct your test without the benefit of the agency’s comments, albeit at a slightly elevated risk that the FDA might challenge your approach afterward. Note that our team can help reduce the likelihood of such challenges by spotlighting any deviations from what we know to be FDA’s preferred approach to HF validation testing. That said, if we (or other consultants for that matter) help you develop your protocol, you’re more likely to avoid a challenge from the FDA because the protocol will likely be well-aligned with their guidance and the current standard of care.
  • Whether or not FDA can review your protocol, we advise a conservative approach to testing, as follows:
    • Err on the side of including more rather than fewer user groups if you are “on the fence” as far as grouping is concerned. Include a strong rationale in your protocol (and subsequent test report) regarding how you identified distinct user groups.
    • Be sure to include at least 15 test participants per user group in the test.
    • Make sure you provide representative (i.e., reasonably real-world) training to test participants, noting that this might mean providing no training at all for some devices.

Please reach out to us if you’d like to discuss this topic further.

Michael Wiklund, CHFP, P.E., is General Manager of Emergo by UL’s HFR&D division, and Allison Strochlic, CHFP, is Research Director at HFR&D.

Learn more about US FDA human factors engineering (HFE) and usability requirements for medical devices:


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