What the study tested
Today's low-dose CT screening eligibility hinges on pack-years — a number that multiplies daily packs by years smoked — plus a rule about how recently a person quit. The current U.S. Preventive Services Task Force recommendation covers adults aged 50 to 80 with at least a 20 pack-year history who currently smoke or quit within the past 15 years. It works, but it is awkward to compute and, the authors argue, misses people who would benefit.
In a research letter published in JAMA Internal Medicine on June 29, 2026, Lauren E. Kearney, MD, and colleagues tested a simpler idea: use total years smoked as the threshold. They analyzed 2024 National Health Interview Survey data covering more than 57 million ever-smoking adults aged 40 to 80, using the Life-Years from Screening–CT (LYS-CT) model to compare current USPSTF criteria against three alternative thresholds — 20, 30, and 40 or more years smoked.
The point of the exercise was not just to widen the net, but to see how well each rule separates the people most likely to gain life-years from screening from those least likely to.
The headline result
A 30-year smoking-duration threshold captured about 97% of the highest-benefit individuals, versus roughly 77% under current USPSTF criteria — while still excluding about 96% of the lowest-benefit individuals. In other words, a single, easier-to-apply number matched or beat the more complex pack-year rule at finding the people screening helps most.
The trade-off shows up in the size of the eligible population. Loosen the threshold and you catch more high-benefit patients — but you also invite in more people who benefit little, and you generate far more scans.
| Criterion | High-benefit captured | Eligible population | Low-benefit excluded |
|---|---|---|---|
| Current USPSTF (≥20 pack-years) | ~77% | 11.4 million | — |
| ≥40 years smoked | ~85% | ~10 million | ~100% |
| ≥30 years smoked | ~97% | ~20 million | ~96% |
| ≥20 years smoked | ~99% | >32 million | lower |
Figures rounded as reported in the JAMA Internal Medicine research letter. High-benefit capture and eligibility estimates are modeled from 2024 NHIS data.
A clinical improvement is a capacity problem in disguise
The 30-year threshold roughly doubles the eligible population, from 11.4 million to about 20 million. The 20-year threshold pushes it past 32 million. Even accounting for the fact that not everyone eligible actually gets screened, a change of this magnitude points in one direction: more annual low-dose chest CTs to acquire, read, and report.
Scanner time is rarely the binding constraint. Reporting is. Each screening CT needs a careful read for nodules, comparison against priors, standardized Lung-RADS categorization, and a documented follow-up recommendation — repetitive, high-volume work layered on top of an already stretched radiology workforce. Broaden eligibility and that workload grows whether or not headcount does.
The study's authors are explicit that this is a policy trade-off, not a free win. As they put it, decision makers must weigh these trade-offs according to priorities such as resource availability. Capacity is one of those priorities — and it lives largely in the reporting queue.
What broader eligibility asks of a screening program
Three consequences follow for any program that grows its screened population:
Volume rises faster than staffing
Doubling eligibility does not come with double the radiologists. Programs that scale intake without scaling reporting capacity push turnaround times up and risk missing the follow-up windows that make screening effective in the first place.
Consistency matters at scale
Screening reporting is standardized work — nodule measurement, Lung-RADS categorization, structured follow-up. Variability across readers is a known problem, and it grows with volume. Structured drafting helps keep every read to the same template.
The bottleneck moves downstream
Once more people are eligible, the pressure lands on the report, not the scanner. A program that can only expand by hiring will scale slowly; one that can lift per-radiologist throughput can meet demand without proportional headcount growth.
Where AI CT reporting fits
If broader criteria arrive, the lever that lets screening scale is throughput per radiologist — not just more radiologists. This is where AI CT reporting is relevant. Rather than flagging a single finding, a foundation-model approach can produce a comprehensive, structured draft for each low-dose chest CT — nodules described and measured, categorized, and formatted into a report a radiologist reviews and signs.
The radiologist stays in the loop and remains accountable for every final read. What changes is where their time goes: less repetitive drafting and measurement, more clinical judgment. That is what turns a doubling of eligible patients into a manageable increase in workload rather than a backlog.
A ready-to-sign report is not a shortcut around the radiologist — it is a way to let screening programs meet demand that policy, not marketing, is about to create.
Frequently asked questions
What are the current USPSTF lung cancer screening criteria?
The U.S. Preventive Services Task Force recommends annual low-dose CT screening for adults aged 50 to 80 who have at least a 20 pack-year smoking history and either currently smoke or quit within the past 15 years. Pack-years multiply the packs smoked per day by the number of years smoked, and the years-since-quitting rule adds further complexity to determining eligibility.
How does a 'years smoked' criterion compare to pack-years for lung cancer screening?
In a 2026 JAMA Internal Medicine research letter analyzing 2024 National Health Interview Survey data on more than 57 million ever-smoking adults aged 40 to 80, a 30-year smoking duration threshold captured about 97% of the highest-benefit individuals, compared with about 77% under current USPSTF criteria, while still excluding roughly 96% of the lowest-benefit individuals. The authors argue total years smoked is simpler to apply and may better identify people likely to benefit from low-dose CT.
Would simpler screening criteria increase CT scan volume?
Yes. In the study, current USPSTF criteria made about 11.4 million people eligible, while a 30-year smoking duration threshold expanded eligibility to roughly 20 million — close to double. A 20-year threshold pushed eligibility above 32 million. Broader eligibility translates directly into more annual low-dose chest CT screening exams that must be acquired, read, and reported.
How can screening programs handle more chest CT volume without adding radiologists?
Reporting, not scanning, is often the bottleneck when screening volume grows. AI CT reporting can generate a structured draft report for each low-dose chest CT that a radiologist reviews and signs, so a program can absorb more studies without expanding radiologist headcount at the same rate. The radiologist remains accountable for every final read; AI handles the repetitive drafting and measurement work that scales with volume.
Source: Kearney LE, et al. "Evaluation of Alternative Smoking Duration Criteria for Lung Cancer Screening," JAMA Internal Medicine, June 29, 2026 (doi.org/10.1001/jamainternmed.2026.2732), with accompanying commentary (doi.org/10.1001/jamainternmed.2026.2741), as reported by Radiology Business and AuntMinnie. Figures are rounded as reported.