Statistics and Its Interface

Volume 14 (2021)

Number 2

Lead time distribution for individuals with a screening history

Pages: 131 – 149

DOI: https://dx.doi.org/10.4310/20-SII622

Authors

Ruiqi Liu (Department of Bioinformatics and Biostatistics, University of Louisville, Kentucky, U.S.A.)

Dongfeng Wu (Department of Bioinformatics and Biostatistics, University of Louisville, Kentucky, U.S.A.)

Shesh N. Rai (Department of Bioinformatics and Biostatistics, University of Louisville, Kentucky, U.S.A.)

Abstract

We derived the distribution of lead time for periodic screening in the future when an individual has a screening history with negative results. It is a mixture of a point mass at zero and a positive sub-PDF. The motivation comes from the reality that for people in older age, they may already have some screening exams for targeted cancer before and still look healthy and are asymptomatic at their current age. How to evaluate their future screening result is a challenge. We explored how the screening history would affect the lead time if one would be diagnosed with cancer in the future. Simulations were carried out on combinations of different initial screening age, current age, sensitivity, mean sojourn time, and screening schedule in the past and in the future. The method developed can be applied to periodic exams for any kind of chronic disease, such as cancer. We applied our new method of evaluating the lead time distribution for male and female heavy smokers using low-dose computed tomography in the National Lung Screening Trial.

Keywords

lead time, sensitivity, sojourn time, screening, transition density

Full Text (PDF format)

Received 19 September 2019

Accepted 13 May 2020

Published 22 December 2020