Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Statistical Methods for Biomarkers

Aiyi Liu
  • Aiyi Liu, PhD, Senior Investigator, Biostatistics and Bioinformatics Branch, DiPHR
  • Jin Yang, PhD, Visiting Fellow
  • Brisilda Ndrika, MS, PhD, Postdoctoral Intramural Research Training Award Fellow

Aiyi Liu’s research in 2025 focused on the development of methods for evaluating biomarkers for disease prediction and classification, specifically for estimating the accuracy of diagnostic biomarkers such as Youden’s index and the area under the receiver operating characteristic curves when only data from a group-testing are available. The methods have the advantage of saving cost and time, protecting study participants’ confidentiality, and potentially resulting in better estimation of the biomarker’s diagnostic accuracy.

Publications

  1. Dong S, Li Z, Li Y, Liu A. On the optimal combination of elliptically distributed biomarkers to improve diagnostic accuracy. Genes (Basel) 2024 15:1145
  2. Yang J, Liu A, Perkins N, Zhen C. Youden index estimation based on group-tested data. Stat Methods Med Res 2025 34:45-54
  3. Cai X, Zhang W, Li H, Li Z, Liu A. Estimation of ROC curve when case and control require different transformations for normality. Stat Methods Med Res 2025 34:1982-1993

Contact

For more information, email liua@mail.nih.gov or visit https://www.nichd.nih.gov/about/org/dir/dph/officebranch/bbb/liu.