The American Lung Association's (ALA) 2024 State of Lung Cancer report showed an increase in national lung cancer screening (LCS) rates from 4.5% in 2023 to 16% in 2024 -- a shift likely due to a change in methodology, according to researchers.
For its 2024 report, the ALA used data from the Behavioral Risk Factor Surveillance System (BRFSS) rather than from the American College of Radiology (ACR) Lung Cancer Screening Registry (LCSR), wrote a team led by Peter Gunderman, MD, of the Indiana University School of Medicine in Indianapolis. The group's commentary was published April 2 in the American Journal of Roentgenology.
"[The rate increase] requires careful examination as it alters our understanding of screening implementation progress," the authors noted.
This near-tripling of screening rates is not a reflection of improved screening practices, but of a change in data collection methodology, according to Gunderman and colleagues. The BRFSS is a telephone-based health survey conducted by the U.S. Centers for Disease Control and Prevention and consists of information from more than 400,000 interviews with adults each year. The ALA's switch to using this data for its report coincided with the U.S. Centers for Medicare and Medicaid Services' (CMS) removal of the requirement for facilities to report lung cancer screening exams to a registry -- specifically the ACR's LCSR.
"The removal of the reporting requirement created a confounding effect -- the flatlining of ACR registry data likely reflects decreased reporting rather than actual screening patterns, making it impossible to disentangle true screening trends from methodologic artifacts," the group explained. "Had the most recent State of Lung Cancer report published in 2024 continued use of ACR registry data, the national screening rate would have been 4.5% -- essentially unchanged from the previous year."
The ACR's LCSR has been key to the early implementation of LCS following CMS's 2015 coverage decision, the authors noted. Its strengths include detailed clinical data collection, standardized reporting through Lung-RADS, and quality metrics beyond screening completion rates. But it also has limitations as a population-level screening measurement tool, relying on facility reporting (which became increasingly incomplete once the reporting requirement was removed) and capturing screening performed at participating facilities only.
The BRFSS, in contrast, provides a "more comprehensive population approach," according to the authors. In 2022, it included questions about LCS. Yet it also has limitations: "Self-reported health behaviors may be subject to recall bias, social desirability bias, or confusion about what constitutes an eligible screening examination," Gunderman and colleagues noted, and [telephone] survey methodologies can also underrepresent certain high-risk populations, including those with limited telephone access or language barriers."
In any case, the increase in reported LCS rates reported by the ALA carries important implications, according to the investigators, who listed the following recommendations:
- "Radiologists should approach historical screening rate comparisons with caution, recognizing the fundamental methodologic differences between pre-2024 and current ALA reports."
- "The higher screening rate of 16% suggests a need to reassess assumptions about current screening capacity and future needs. Rather than assuming that 95% of eligible individuals remain unscreened, programs might shift resources toward more targeted approaches for reaching the remaining unscreened population."
- "With reduced registry participation, it becomes more challenging to ensure consistent quality in screening implementation. Radiologists should consider voluntary participation in the ACR registry even without the CMS mandate to maintain quality standards and contribute to the accruing evidence base."
"[This methodologic] change highlights the critical need for consistent, reliable measurement methods for tracking preventive health services," the team concluded.
The complete viewpoint can be found here, and the ALA's report can be found here.
