RADx Tech Program tackles design of accessible COVID-19 home tests


Science Highlights
July 24, 2023
Raymond A. MacDougall

Best practices for industry could prompt the design of new tests for people with disabilities

Under public health peril posed by the global COVID-19 pandemic in 2020, biomedical device manufacturers quickly developed an array of home test kits for most of us to self-test and determine our individual SARS-CoV-2 infection status. The first at-home COVID-19 diagnostic test received emergency use authorization from the U.S. Food and Drug Administration (FDA) in December 2020. At the end of the COVID-19 Public Health Emergency in May 2023, FDA had amassed a list of three dozen authorized over-the-counter tests on its website.

An elderly woman holds COVID-19 test kit parts

RADx Tech has developed best practices document for accessibility considerations in design of COVID-19 diagnostic test kits. Shutterstock photo 

RADx Tech, administered by the National Institute of Biomedical Imaging and Bioengineering (NIBIB), and an arm of the wider NIH RADx initiative, supported the manufacturers of many of the newly authorized tests. Authorized at-home rapid tests gained a new prominence in helping people detect their infection status, make decisions about daily activities, prevent the spread of the SARS-CoV-2 virus, and receive appropriate treatment.

Attention to accessibility

Despite the paradigm shift to self-testing that most people experienced, the COVID-19 diagnostics phenomenon bypassed a significant population sector, including people with low or no vision, reduced dexterity or motor skills, and older adults. The ways that inaccessibility has manifested could be readily identified by those it affected. Complicated instructions, small kit components that require dexterity to handle, liquids needing precise dispensing, result readers exclusively for sighted people, all conspired against many test kits meeting basic accessibility measures.

“When we thought we might have met our at-home diagnostics objective, we found out that there was something missing,” said Jill Heemskerk, Ph.D., deputy director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB) at NIH and co-lead of the RADx Tech program. “With the crack team assembled to address the at-home diagnostics challenge, we headed back to work on a further challenge of making accessible tests.”

Alerted to this oversight by accessibility advocates, RADx Tech committed resources in early 2022 for increased accessibility of COVID-19 home tests. The RADx Tech Accessibility Program subsequently invited collaboration from advocacy organizations to contribute to design insights and is a first step that will help manufacturers address the gap in accessible test availability.

A listening session held in March 2022, brought together leaders of accessibility advocacy organizations and federal agencies to better understand specific needs. The preliminary assessment of the group was that no published standards could be found that are associated with accessible design requirements. The  group set to the task of addressing this gap in the design of diagnostic devices.

“We have been focused on helping industry get it right,” said Brian Walsh, RADx Tech Accessibility Program Manager. “In order to come up with an effective accessibility solution, you need to look at the process from end-to-end. That means from acquisition of the kit to disposal of the kit components. The most important point of all is that accessible design adds value for all users.”

Fastep COVID-19 Antigen Pen Home Test produced by Azure Biotech, Inc.

FDA authorized the Fastep COVID-19 Antigen Pen Home Test from Azure Biotech, Inc. on April 14, 2023. NIBIB photo by Chia-Chi (Charlie) Chang

A more accessible COVID test

This past spring, the FDA authorized Azure Biotech, Inc.’s at-home COVID-19 test evaluated by RADx Tech’s Accessibility Program. The Fastep COVID-19 Antigen Pen Home Test received accelerated regulatory review as part of RADx Tech’s Independent Test Assessment Program.

The Azure pen is an extremely simple test. It has only two parts and its use requires far fewer steps than other marketed tests. Based on advice from the RADx Tech accessibility program, design principles for accessibility were incorporated into the final device.  The “pen” has a built-in nasal swab to collect the sample combined with a test strip to show results. The user collects the sample, inserts the test pen into a base, and waits 15 minutes before checking the display area of the pen for a result. There is no need to transfer liquids, manipulate small parts or understand complex instructions.

“The Azure pen is the first at-home COVID-19 diagnostic test with features that conform to the newly defined accessible design principles,” said Heemskerk.

RADx Tech’s support for accessible test development

This past fall, RADx Tech expanded its support to develop tests that are universally accessible. In September 2022, NIBIB issued a solicitation for the next generation of COVID-19 diagnostics that ensure the broadest possible ease of use and improved performance with a specific track to develop accessible over-the-counter tests that can be used independently by people with disabilities. The RADx Tech team has been working with manufacturers in the next generation of tests and accessibility categories and are now in the development phase of the accelerated innovation funnel—the signature element of the RADx Tech program. Their devices are planned for roll-out over the coming months.

A team of RADx Tech and accessibility experts are actively working with the test manufacturer hopefuls to address device design, packaging, and modes of instruction, among other challenges. Advocacy groups and individuals continue to be engaged to help provide feedback on device usability and troubleshoot design challenges for the intended users.

Accessibility best practices for test developers

By January of this year, the group had made sufficient progress to post a preliminary version of Best Practices for the Design of Accessible COVID-19 Home Tests, partnering with the U.S. Access Board for publication on their website. The document captured lessons from more than a year of analysis and consultation with accessibility-focused advocacy groups, university-based subject matter experts, industrial design experts, and test kit manufacturers. The finalized Best Practices for the Design of Accessible COVID-19 Home Tests was posted to the U.S. Access Board site in July 2023 and provides a blueprint for the design and manufacture of more accessible diagnostic tests.

The Best Practices document provides recommendations on the design of COVID-19 diagnostic test kits for people with no or low vision, people with reduced manual dexterity and older adults.

“Accessible design in manufacturing of biomedical devices allows a wider spectrum of users to benefit from these important tools that help people manage their health,” Heemskerk said. “The recommendations we outline in the Best Practices document apply directly COVID-19 home tests but are readily transferable to home devices  for other health conditions and diseases.”

Guiding principles for universal design of COVID-19 home tests:

Engage target end users.

Simplify workflow.

- Fewer steps are easier to document, manage, and execute.

- Fewer components are easier to identify and handle, and are less likely to be misplaced.

- Intuitive and familiar design elements and nomenclature reduce ambiguity.

Provide multi-modal test instructions.

- Provide both physical and digital test instructions.

- Provide digital test instructions on an accessible webpage, as a downloadable document, and in a closed-captioned video tutorial with descriptive audio.

Eliminate the need for precision, where possible.

- Steps that require precision (e.g., liquid transfer, counting drops, aligning parts with tight tolerances) may cause barriers to independent completion and increase potential for use error.

Avoid small components.

- Larger components are easier to manipulate and see. They are less likely to be misplaced.

Incorporate simultaneous nonvisual and visual cues.

Illustrations should be simple, high-contrast, shaded line drawings with alt text.

—from Best Practices for the Design of Accessible COVID-19 Home Tests

About the RADx Initiative

The RADx initiative was launched on April 29, 2020, to speed innovation in the development, commercialization, and implementation of technologies for COVID-19 testing. The initiative has four programs: RADx Tech, RADx Advanced Technology Platforms, RADx Underserved Populations and RADx Radical. It leverages the existing NIH Point-of-Care Technology Research Network. The RADx initiative partners with federal agencies, including the Office of the Assistant Secretary of Health, Department of Defense, the Biomedical Advanced Research and Development Authority, and U.S. Food and Drug Administration. Learn more about the RADx initiative and its programs: https://www.nih.gov/radx.