On May 13, 2021, the Centers for Disease Control and Prevention (CDC) announced that those fully vaccinated against COVID-19 would no longer need to wear masks in most situations. But this has raised concerns about how to accurately verify one’s vaccination status. While digital health passes may seem like a straightforward solution, in reality a lack of healthcare data standardization means that’s not necessarily true.

There are several fundamental data issues that must be considered when creating such passes to ensure that they serve the needs of businesses and organizations who want to reopen safely. In part one of this two-part blog series, we’ll look at the basics behind creating a digital health pass. For part two, we’ll look toward international travel, and how different vaccines worldwide further complicate the issue of interoperability in healthcare.

What data should be collected?

The fundamental question here concerns what exactly is being proven with this particular digital health pass. Ultimately, it should convey enough information to reliably verify that the holder is at a low risk for transmitting the SARS-CoV-2 virus. Yet merely certifying that a vaccination has occurred is not akin to confirming someone is low risk.

To be considered fully vaccinated (and by extension, low risk) the CDC requires that at least 14 days have passed since receiving the final dose of a vaccine. For a one-dose vaccine, this is two weeks after the first (and only) dose and, for a two-dose vaccine, two weeks after the second (final) dose. But the pass must also ensure the two doses were administered within the proper timeframe.

This means a digital health pass needs additional data elements – such as vaccine manufacturer, dose number, and dates of administration – before definitively verifying someone’s vaccination status. And a similar issue occurs for reporting negative test results. Depending on the type of test performed (e.g., PCR or rapid antigen), additional data on the date and type of test performed would be needed to determine the holder’s status.

Aggregation supports a complete, comprehensible picture

Next, we must figure out how to pull together all the requisite information into a single, complete record that can be easily accessed. Data may need to be integrated from several different authoritative sources, which may use different clinical terminologies or code sets. For instance, a person’s prior testing results could reside in an electronic health record (EHR) while their COVID-19 vaccination records only exist in their state’s immunization information system (IIS). Mapping data elements to a common clinical terminology could help normalize and integrate data to form a complete and comprehensible picture of the health status of the individual.

Digital health passes are key to safe reopening

Without careful consideration of these fundamental data issues, digital health passes could become unreliable – causing loss of trust among world leaders and the general population. What’s more, information requirements may differ depending on the use case, which could require more data collection.

Deciding whether it is appropriate for an individual to participate in a particular situation or activity without precaution requires complex decision-making. Clinical information aggregated from disparate sources may need to be mapped to standard code sets to drive decision-making logic. Data normalization will rely on relevant and specific clinical terminology along with precise, clinically vetted value sets, or groups of codes used to query data. These tools can help developers of health passes use data to create a seamless and complete picture of the user. This could then be employed to satisfy entrance criteria in different scenarios, for example at a concert, an office, or for air travel. Smart clinical terminology solutions can help developers create advanced credentialing solutions that are critically needed to ease the transition into a mask-optional society.

Check out part two of this series, where we examine the additional issues that arise when working to create an international health pass.