Graduating PhD candidates

Kristen pictureKristen Aiemjoy, MSc (2013)

Education: Georgetown University, School of Foreign Service (BS Global Health); London School of Hygiene and Tropical Medicine (MSc Public Health)

My research interests are in evaluating measurement diagnostic tools used in very resource limited settings. My dissertation work has focused on validating and improving caregiver-reported diarrhea, the primary outcome measure of pediatric diarrhea used in both clinical research and epidemiology. In 2016, I was awarded an NIH National Research Service Award from the National Institute of Child Health and Development. Before coming to UCSF, I worked as an epidemiologist in Africa; in Ethiopia, South Sudan, Tanzania, Uganda and South Africa for a variety of organizations including universities, research institutes like the Ifakara Research Institute and aid organizations like Doctors without Borders. 

Dissertation Title: “Defining Diarrhea: A population-based validation study of caregiver-reported stool consistency in the Amhara region of Ethiopia”


Sarah webSarah Ackley, BS (2013) 

I am interested in mathematical modeling of tuberculosis and other infectious diseases. Working in Travis Porco’s research group at UCSF, I am currently studying tuberculosis epidemics in communities of First Nations (native) Canadians in the early 20th century.  I also have been working in the Immunizations branch at the California Department of Public Health on measles surveillance in California. As a graduate student at UCSF, I am interested in continuing to learn about epidemiology and medicine, as well as statistics. As a graduate student, I am potentially interested in continuing work on tuberculosis modeling with molecular data.


Caroline Tai MPH (2013)Caroline web


I am interested in genetic epidemiology for cancer outcomes, specifically how to characterize disease risk using germline genetic information and other molecular biomarkers. My previous work experiences in drug development, public health, and clinical research motivate me to pursue research that translates scientific discoveries into practical applications. While at UCSF, I hope to improve our understanding of disease etiology and risk stratification for aggressive prostate cancer screening and treatment by investigating the underlying genetic architecture and developing new tools for disease prediction. I am also a member of the Witte Lab here at UCSF (

Research interest:

Genetic epidemiology, cancer, risk prediction, genomics, genome-wide association studies (GWAS)

Dissertation Title: Heritable Risk Factors for Aggressive Prostate Cancer


Kathryn web

Kathryn Ray, MA (2013)


My background includes experience in epidemiological ophthalmic medical research as well as statistical programming and analysis. In the PhD program, I’d like to expand and cement my epidemiological and statistical methods as well as learn more about RCTs (Bayesian methods applied to RCTs, adaptive trials, and large simple trials). I’m also interested in analysis methods with large data sets in medical research, for example, RCTs collecting samples for deep sequencing (microbiomes), social network data for detecting epidemics, or analysis of large simple trial data.  My goal is to encompass my technical skills along with epidemiological and scientific knowledge in order to contribute to more to medical research.