The critical role of engineering in the rapid development of COVID-19 diagnostics: Lessons from the RADx Tech Test Verification Core

Abstract

Engineering plays a critical role in the development of medical devices, and this has been magnified since 2020 as severe acute respiratory syndrome coronavirus 2 swept over the globe. In response to the coronavirus disease 2019, the National Institutes of Health launched the Rapid Acceleration of Diagnostics (RADx) initiative to help meet the testing needs of the United States and effectively manage the pandemic. As the Engineering and Human Factors team for the RADx Tech Test Verification Core, we directly assessed more than 30 technologies that ultimately contributed to an increase of the country's total testing capacity by 1.7 billion tests to date. In this review, we present central lessons learned from this "apples-to-apples" comparison of novel, rapidly developed diagnostic devices. Overall, the evaluation framework and lessons learned presented in this review may serve as a blueprint for engineers developing point-of-care diagnostics, leaving us better prepared to respond to the next global public health crisis rapidly and effectively.

Fig. 1.. RADx engineering design and human factor readiness and maturity verification process.

Our evaluations focused on the technology, functionality, and manufacturing readiness based on the scale, outcome, and a variety of factors for each parameter.

Fig. 2.. Average TRL and usability scores of evaluated technologies.

Evaluated technologies were broadly broken down into the following categories based on the underlying virus detection method: polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), direct antigen detection, and volatile organic compound (VOC) analysis. Both usability scale and TRL are reported on a 1 to 9 scale. A lower usability score indicates as the most usable, and a higher TRL indicates as the most technical maturity. 1 – usability score was used to put highly usable and technologically mature technologies on the same scale.

Fig. 3.. Technology breakdown of assessed RADx Tech projects.

Note that some tests can use multiple sample types, so percentages do not add to 100%.

Fig. 4.. Sample F&F matrix for usability evaluation.

This homegrown scale enables the assessment of new technology along two usability dimensions: error and efficiency.

Fig. 5.. Failure modalities for evaluated technologies.

Failure modalities could be generally categorized into three major groups: poor manufacturability, lack of robust design, and poor usability.