Speaker
Description
Most infectious disease datasets are dichotomous, typically indicating the presence or absence of infection. However, many contain quantitative measurements, such as cycle threshold (Ct) values from PCR tests or antibody titers from serological assays. Despite this, epidemiological models often rely on dichotomised data to infer key immunological and transmission parameters. This simplification discards valuable information embedded in the original quantitative measurements (\cite{cohen_cost_1983}).
In this work, I will first quantify the information loss incurred by dichotomising quantitative data using metrics such as the Kullback–Leibler (KL) divergence. I will then present a framework for incorporating quantitative measurements, specifically Ct values and antibody titers, into epidemiological models to capture population-level dynamics better. I will apply this framework to COVID-19 data in the United Kingdom and explore different testing settings and data availability scenarios. Finally, I will discuss the practical considerations and methodological advantages of using quantitative data over dichotomised alternatives, highlighting implications for inference, model accuracy, and public health decision-making (\cite{alahakoon2025tracking}).
Bibliography
@article{cohen_cost_1983,
title = {The {Cost} of {Dichotomization}},
volume = {7},
copyright = {https://journals.sagepub.com/page/policies/text-and-data-mining-license},
issn = {0146-6216, 1552-3497},
url = {https://journals.sagepub.com/doi/10.1177/014662168300700301},
doi = {10.1177/014662168300700301},
language = {en},
number = {3},
urldate = {2025-04-11},
journal = {Applied Psychological Measurement},
author = {Cohen, Jacob},
month = jun,
year = {1983},
pages = {249--253},
}
@article{alahakoon2025tracking,
title={Tracking West Nile virus dynamics using viral loads from trapped mosquitoes},
author={Alahakoon, Punya and Marchinton, Ian and Fauver, Joseph R and Hay, James A},
journal={bioRxiv},
pages={2025--07},
year={2025},
publisher={Cold Spring Harbor Laboratory}
}
