Objective: To estimate the potential effects, on costs and outcomes, of changes in sensitivity and specificity associated with new screening methods for cervical cancer in the military.
Methods: A Markov model of the natural history of cervical cancer was created to simulate a cohort of 100,000 military beneficiaries aged 18-85. Probability estimates for various outcomes and the accuracy of screening tests were obtained from the literature. Cost estimates were obtained from military sources where available; otherwise, civilian costs were used. The outcomes and costs of conventional cytology, liquid-based cytology, and liquid-based cytology with human papillomavirus (HPV) triage were compared at 1-, 2-, and 3-year screening frequencies.
Results: Marginal reductions in the incidence of cervical cancer from increasing screening sensitivity are greater than reductions in cancer mortality at every screening interval. Incremental improvements in both cancer incidence and mortality are higher at less frequent screening intervals. Increases in the ratio of low- to high-grade lesions result from increasing the sensitivity of the screening test or shortening the screening interval. Both liquid-based cytology and liquid-based cytology with HPV testing are cost effective (less than $50,000 per life-year saved) when performed at 3-year screening intervals. However, neither strategy is cost-effective when performed more frequently than every 3 years.
Conclusion: Use of a more sensitive cervical cancer screening test increases costs. However, a more sensitive test performed less frequently may be more effective and less expensive than conventional cytology done annually. In the military setting, this has significant implications for both expense reduction and readiness enhancement.