Risk-based lung cancer screening thresholds modeled to maximize value in Singapore

Low-dose computed tomography (LDCT) saves lives in lung cancer screening, but its high cost has kept uptake limited in many countries. A new modeling study from Singapore argues that the answer is not simply to screen more people, but to screen the right people, using individualized risk thresholds anchored to what the health system is willing to pay for a year of healthy life.

Researchers built a lifetime Markov model simulating costs and health outcomes for Singaporean smokers and never-smokers with a family history of lung cancer, analyzed separately for men and women. Transition probabilities and costs were drawn from local data, while quality-of-life utilities came from published sources. All outcomes, including costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs), were discounted at 3% annually.

The team compared conventional LDCT eligibility, based on age and smoking history, against no screening and against a menu of risk-based strategies. These varied the age at which screening begins (50, 55, or 60) and the frequency (annual, biennial, or triennial). Using a validated local risk prediction model, reverse threshold analyses identified the risk cut-offs at which screening remains cost-effective across willingness-to-pay thresholds of SGD 45,000 to 75,000 per QALY.

Among smokers, annual risk-based screening starting at age 50, with 1-year risk thresholds of at least 0.37% for males and 0.51% for females, produced the largest health gains, delivering 0.201 and 0.198 additional QALYs respectively compared with no screening. However, the same risk-based annual screening starting at age 60 was the most economically efficient option, yielding 0.177 and 0.182 additional QALYs at incremental ICERs of SGD 40,155 and SGD 42,666 per QALY.

The findings for never-smokers with a family history of lung cancer were particularly striking, because conventional LDCT criteria were not cost-effective for this group at all. Annual risk-based screening from age 50 in males at a 1-year risk threshold of at least 0.16%, and in females at 0.21%, maximized health gains, with 0.013 and 0.021 additional QALYs respectively.

Yet for never-smokers, less intensive screening from age 60 proved more economically efficient: biennial screening in males at a 1-year risk of at least 0.20% and triennial screening in females at 0.21%, producing 0.007 and 0.011 additional QALYs at incremental ICERs of SGD 73,548 and SGD 26,953 per QALY. The authors suggest that these different screening intensities offer implementation options under varying budget constraints.

The study’s conclusions are cautious. The authors state that risk-based LDCT screening may improve screening efficiency and health gains while maintaining good value for money, but that further research is needed to support its implementation in practice. As a decision-analytic model rather than a clinical trial, the analysis projects expected outcomes under modeled assumptions rather than demonstrating results in a screened population, and its findings are specific to the Singaporean context and the local data used to parameterize the model.

Even so, the work addresses a pressing regional problem. The authors note that Asia carries a high burden of lung cancer among never-smokers, a group that conventional smoking-based eligibility criteria largely exclude. By anchoring eligibility thresholds to explicit willingness-to-pay values, the framework aims to give policymakers a transparent way to set screening eligibility that reflects both epidemiology and budget realities.

The study, published open access in BMC Medicine, is presented as evidence to inform risk-based screening eligibility and implementation strategies, particularly in Asian settings. Its central message is that precision screening, in which the threshold for referral depends on an individual’s calculated risk rather than age and smoking history alone, could stretch screening budgets further while directing LDCT toward those most likely to benefit.

Subject of Research: Cost-effectiveness modeling of risk-based lung cancer screening eligibility thresholds in Singapore

Article Title: Optimizing precision lung cancer screening using willingness-to-pay–anchored risk eligibility thresholds

Article References: Juang, Y. R., Zhang, Y., Yii, A. C. A., Dickens, B. L., He, Y., Jin, S., Lim, L. H. M., Seow, W. J., & Chen, W. (2026). Optimizing precision lung cancer screening using willingness-to-pay–anchored risk eligibility thresholds. BMC Medicine. https://doi.org/10.1186/s12916-026-05360-3

Image Credits: AI Generated

DOI: 10.1186/s12916-026-05360-3

Keywords: lung cancer, LDCT screening, cost-effectiveness, Singapore, risk thresholds, QALYs, Markov model, never-smokers, family history, health economics, screening eligibility, BMC Medicine