Modeling inequalities helps to develop cervical cancer screening strategies that can improve outcomes and reduce disparities
Research Activities, May 2012, No. 381
The two fundamental goals of improving population health and distributing that health fairly are frequently in tension, because measures to improve one may not be optimal for and may conflict with the other. Researchers devised a typology of cancer disparities among black, white, and Hispanic populations in the United States that differentiated inequalities resulting from different factors, such as care access and quality of treatment and prevention. By explicitly modeling disparities between subgroups, they identified prevention strategies that could reduce the risk of cervical cancer overall, distribute health benefits equitably, and use health care resources efficiently. With a disease-simulation model of cervical cancer, they applied this typology to an evaluation of different screening and vaccination strategies in which the health and economic outcomes were calculated for the average population, and also for the three subgroups separately.
The researchers identified strategies that reduced the overall risk of cervical cancer by 60 percent to 74.5 percent, and that improved cancer outcomes in all racial subgroups. However, they also found that the benefits were unequally distributed. For example, one strategy using Pap smears and human papilloma virus (HPV) triage (cytology followed by HPV DNA testing) resulted in an average reduction of 69 percent in cancer incidence overall, but a 71.6 percent reduction for white women, 68.3 percent for black women, and 63.9 percent for Hispanic women.
The researchers found that screening strategies that directly targeted racial subgroups bearing the greatest inequalities provided a more equitable distribution of benefits. For example, reduction in cervical cancer incidence was 69.7 percent in white women versus 70.1 percent in Hispanic women. These strategies were also more effective and less costly than current screening patterns. Strategies that included adolescent HPV vaccination at coverage rates of 33 percent and targeted screening with new screening algorithms had a cost-effectiveness ratio of $28,200 per year of life saved when compared with the same strategy without vaccination. The disease-simulation model the researchers used was calibrated to epidemiological data for the United States. The researchers calculated the average reduction in cervical cancer incidence overall and for black, white, and Hispanic women under five different prevention strategies. This study was supported in part by the Agency for Healthcare Research and Quality (HS15570).
See "Model-based analyses to compare health and economic outcomes of cancer control: Inclusion of disparities" by Sue J. Goldie, M.D., and Norman Daniels, Ph.D., in the Journal of the National Cancer Institute 103, pp. 1373-1386, 2011.