01 Apr 2026
Rheumatoid arthritis (RA) is a chronic autoimmune condition that can cause progressive joint damage if it is not detected and managed early. Laboratory testing is a central part of diagnosis and long‑term disease monitoring.
New peer-reviewed research published in ACR Open Rheumatology leverages more than a decade of real‑world laboratory data from Labcorp, offering a rare, real-world view into how RA testing patterns—and the healthcare workforce delivering that care—have evolved across the United States.
Using real‑world data to understand care delivery
Labcorp researchers analyzed RA‑related lab tests ordered through Labcorp between 2012 and 2024, representing more than 9,000 healthcare providers nationwide. These included rheumatology specialists, primary care doctors, and advanced practice providers (APPs), such as nurse practitioners and physician assistants.
The study examined three broad categories of testing:
- Diagnostic tests, which that help initial RA identification
- Newer biomarker panels, designed to improve diagnostic accuracy
- Monitoring tests, used to track disease activity over time
Key insights from the study
- Advanced practice providers are playing an increasingly important role.
The number of rheumatology nurse practitioners and physician assistants regularly ordering RA tests through Labcorp grew more than fourfold over the study period, reflecting their expanding presence on care teams. - Comprehensive testing is becoming more common.
Use of diagnostic panel tests that combine multiple biomarkers increased substantially, particularly among rheumatology providers, supporting efforts to improve diagnostic confidence and efficiency. - Testing practices are becoming more aligned across provider types.
Differences in test positivity between physicians and APPs narrowed over time, suggesting greater consistency in patient evaluation and test use.
Why Labcorp’s data matters
This research highlights how Labcorp’s national laboratory network and broad test menu make it possible to study real‑world healthcare trends at scale. By combining scientific expertise, a broad test portfolio, and one of the largest longitudinal laboratory datasets in the country, Labcorp helps generate evidence that supports more informed decision‑making and improved patient care.
The publication was co-authored by Dr. Sarah (Min Kyung) Lee, Ph.D., Lead Data Scientist, Data Science and Real-World Evidence at Labcorp. Dr. Lee conducts clinical research studies with Labcorp’s real-world diagnostic laboratory data across various therapeutic areas to help grow Labcorp’s public scientific presence and drive testing through real-world evidence research.