Long-Term Effects of Periodic Cancer Screening for Aged People with a Screening History

• Activity Number: 643
• Type: Contributed
• Date/Time: Thursday, August 7, 2014 : 10:30 AM to 12:20 PM
• Sponsor: International Chinese Statistical Association
• Author(s): Dongfeng Wu*+
• Companies: University of Louisville
• Keywords: over diagnosis ; true early detection ; symptom free life ; sensitivity ; sojourn time ; transition probability

Abstract

This project extends the probability model that Wu et al developed for evaluating long-term effects to aged people with a screening history. Currently asymptomatic people with a screening history are categorized into four mutually exclusive groups: True-early-detection, No-early-detection, Over-diagnosis, and Symptom-free-life. Probability formulae are derived rigorously for each case. These probabilities change with a person's current age, previous screening history, future exam frequency, screening sensitivity, and other parameters. Human lifetime is treated as a random variable by using the actuarial life table from the US Social Security Administration. Simulation studies using the HIP breast cancer data provide estimates for these probabilities and corresponding credible intervals. The model provides important information regarding the proportion of each category in the future for aged individuals with a screening history and potential gain/loss to continue screening at an advanced age.