In October 2023, the U.S. Food and Drug Administration (FDA) released a proposed rule to regulate laboratory-developed tests (LDTs) as medical devices. While approximately 6,700 public comments were submitted during the open comment period, there is not a reliable mechanism to quantify how clinical laboratorians as a sector perceive the proposed rule. To solicit quantifiable feedback on the FDA's proposed rule, a ten-item questionnaire was developed and submitted to clinical laboratory customers of ARUP Laboratories, a national nonprofit clinical laboratory of the University of Utah Department of Pathology. Of 503 clinical laboratory respondents, only 41 (8.2%) support the FDA's proposed rule. 66.9% of respondents work in laboratories that perform LDTs and were therefore asked additional questions regarding the proposed rule. 83.9% of these respondents believe that the proposed rule will negatively impact their laboratories, while only 3.0% believe that they have the financial resources to pay for FDA user fees. 60.9% of respondents anticipate removing tests from their laboratory menus if the proposed rule is enacted, while an additional 33.2% indicated that they do not yet know. Only 11.2% of respondents believe that they would pursue FDA submissions for all of their existing LDTs if the final rule is enacted. The vast majority of respondents (>80%) were either 'extremely concerned' or 'very concerned' about the impact of the proposed rule on patient access to essential testing, financial and personnel resources to comply, innovation, the FDA's ability to implement the proposed rule, and send-out costs and test prices. Respondents indicated that they would rely heavily on reference laboratory partners for advocacy against the proposed rule, testing options, education, and consultation if the rule was enacted. Thematic analysis of open comments revealed strong opposition to the proposed rule and significant concern regarding negative impacts to patient care across clinical laboratory settings.

All authors have completed the ICMJE uniform disclosure form at www.icmje.org/coi_disclosure.pdf and declare: no support from any organization for the submitted work; JRG serves as chief medical officer at ARUP Laboratories and is an employee of the University of Utah; LS is an employee of ARUP Laboratories; LAC is an employee of ARUP Laboratories; no other relationships or activities that could appear to have influenced the submitted work.

This study did not receive any funding

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IRB of University of Utah gave a determination of exemption for this work

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The data that support the findings of this study are available from the corresponding author, JRG, upon reasonable request.