GRAIL vs bioAffinity Technologies (2026)
These two get shelved together as AI cancer detection and they answer different clinical questions. GRAIL's Galleri is a screening test: a blood draw for asymptomatic people, detecting signals across more than 50 cancer types, backed by the largest evidence base in this index and an active FDA Premarket Approval application. bioAffinity's CyPath Lung is a diagnostic aid: a sputum test for a patient who already has an indeterminate lung nodule, where the job is deciding whether to cut. If you are building a population screening program, Galleri is the category. If you are trying to avoid unnecessary bronchoscopies on small nodules, CyPath Lung is the tool, and its 99 percent reported negative predictive value is the number that matters. Buying one instead of the other is a category error.
- The question is screening: finding cancer in people with no symptoms and no known nodule, across more than 50 cancer types from a single blood draw, as an addition to standard of care single cancer screening.
- Evidence depth is the deciding factor: PATHFINDER 2 enrolled 25,490 participants and the NHS-Galleri trial enrolled more than 140,000 asymptomatic participants, the only prospective randomized controlled trial of population screening with a multi cancer test.
- You want a defined regulatory trajectory: Breakthrough Device designation since 2018 and a Premarket Approval application with its final module submitted to FDA in January 2026.
- The question is diagnosis, not screening: a patient already has a small indeterminate pulmonary nodule found on imaging and the clinical decision is whether to pursue invasive follow up.
- Ruling out matters more than ruling in: the vendor reports a 99 percent negative predictive value in high risk patients with nodules under 20 millimeters, which is the figure that spares patients unnecessary procedures.
- You want a low friction sample: a sputum sample collected at home, analyzed by flow cytometry with automated ML analysis, with results typically returned to physicians in about two days.
This comparison is published by AI Health Index, an independent research platform that compares healthcare AI vendors objectively. GRAIL and bioAffinity Technologies are each graded against the same capability taxonomy, from each vendor's own public materials and the regulatory record, under the AI Health Index verification standard. No vendor pays for placement, and no vendor has reviewed this page. How this evidence is graded
Plain facts
| Fact | GRAIL | bioAffinity Technologies |
|---|---|---|
| Primary category | Diagnostics & Genomics | Diagnostics & Genomics |
| Founded | 2016 | 2014 |
| Headquarters | Menlo Park, California | San Antonio, Texas |
| Website | grail.com | bioaffinitytech.com |
Side by Side
Each record in one paragraph
Written to be quoted whole. Each paragraph states what the AI Health Index verified about the vendor, with the caveats attached. Generated from this pair’s live capability grades, so it moves when a grade moves.
The AI Health Index awards GRAIL its top capability grade on several axes, including Autonomy and Oversight Model, Model and Technology Transparency and Clinical and Operational Evidence. Set against bioAffinity Technologies, GRAIL grades higher on several axes, including Model and Technology Transparency, Model Supply Chain Disclosure and Clinical and Operational Evidence. Grades reflect evidence the AI Health Index could verify at the last review, so a low grade records disclosure the vendor has not published rather than a capability it has been shown to lack.
Source: AI Health Index, July 2026
The AI Health Index awards bioAffinity Technologies its top capability grade on Autonomy and Oversight Model and Setting and Specialty Coverage. Set against GRAIL, bioAffinity Technologies does not grade higher on any scored axis, though the two are level on several axes, including AI Centrality, Autonomy and Oversight Model and Security Certifications and Trust Center. Its thinnest published disclosure sits on Model Supply Chain Disclosure. Grades reflect evidence the AI Health Index could verify at the last review, so a low grade records disclosure the vendor has not published rather than a capability it has been shown to lack.
Source: AI Health Index, July 2026
Questions buyers ask
Should we choose GRAIL or bioAffinity Technologies?
The AI Health Index grades GRAIL higher than bioAffinity Technologies on every axis that separates them, several axes, including Model and Technology Transparency, Model Supply Chain Disclosure and Clinical and Operational Evidence. bioAffinity Technologies does not grade higher on any scored axis.
Where do GRAIL and bioAffinity Technologies differ most?
The widest separation the AI Health Index records between GRAIL and bioAffinity Technologies is on Model and Technology Transparency, where GRAIL grades A and bioAffinity Technologies grades C. That axis sits in the AI Capability group, so it should carry the most weight for a buyer whose binding constraint is how much of the work the model itself is trusted to do.
Where do GRAIL and bioAffinity Technologies grade the same?
The AI Health Index grades GRAIL and bioAffinity Technologies the same on several axes, including AI Centrality, Autonomy and Oversight Model and Security Certifications and Trust Center. Neither holds an advantage the index can evidence on those axes, so they should not carry weight in a selection between these two.
What have GRAIL and bioAffinity Technologies not disclosed?
At the last review, at least one of GRAIL and bioAffinity Technologies published thin or absent detail on Model Supply Chain Disclosure. The AI Health Index treats an absent disclosure as a gap in the public record rather than a failure of the product, so these are the axes to get in writing during diligence instead of inferring from the grade.
Related comparisons
Other published head to head assessments involving these vendors or their closest peers. The full set for this category is on the Diagnostics & Genomics page.
These tests are not substitutes and a buyer choosing between them is usually asking the wrong question. Both are currently offered as laboratory developed tests; neither is FDA approved. Performance figures for both are vendor reported and have not been independently validated by this index. bioAffinity states explicitly that CyPath Lung is not intended as a sole diagnostic tool. Neither vendor publishes a rate card for institutional purchasing.