Biostatistics

Colorectal cancer is one of the most common malignancies in the United States. There is an increasing number of studies using recurrent colorectal adenomas to evaluate the prevention effect for some promising agents. The number of recurrent colorectal adenomas is often measured by performing colonoscopy, which is known to miss a small percentage of existing adenomas and result in misclassification on recurrence status. In addition, some participants might not comply with the schedule of follow-up colonoscopy, which is scheduled to be performed once at the end of the study and, therefore, have variable follow-up lengths compared to the compliant participants. The reasons that a participant cannot comply with the schedule of follow-up colonoscopy could be informative of the risk of recurrence and then bias the results derived from statistical methods that do not adjust for noncompliance. Conventional statistical methods for colorectal adenoma prevention trials cannot simultaneously incorporate misclassification and variable follow-up into analysis and cannot adjust for informative non-compliance without strong assumptions and, furthermore, may incorrectly produce equivocal results for some promising nutritional or chemopreventive agents. The purpose of this application was to develop sophisticated and appropriate statistical models to describe the relationship between the preventive agents and recurrence of colorectal adenomas. We used a latent variable recurrence model, which assumed a portion of non-recurrent participants were misclassified due missing existing adenomas at follow-up colonoscopy, to handle misclassification and a weight function to incorporate the length of follow-up into analysis. The prognostic factors for risk of recurrence was incorporated into the weight function to adjust for potential informative non-compliance. The hope was that a  better understanding of the relationship between preventive agents and recurrence of colorectal adenomas would allow clinical investigators to identify an agent that truly reduces recurrence of colorectal adenomas. This project was funded through a grant from the National Cancer Institute. 

The goal of this project was to conduct laboratory experiments to define the temperature specific Extrinsic Incubation Period (EIP) of Zika virus in Aedes aegypti and to determine if transovarial transmission was possible. This project was funded by a National Science Foundation grant program called Rapid Response Research (RAPID). 

“Chemo-brain”, self-reported cognitive impairment following chemotherapy, is a common complaint among cancer patients and survivors. This study compared a web-based brain-training program to usual care to improve cognitive functioning. Participants were randomly allocated to brain-training or usual care, and followed up post-intervention and 6 months later. We also assessed other important patient-reported outcomes, including fatigue, quality of life, stress, and anxiety. Funding for this project came from the Cancer Council NSW in Australia and the University of Sydney. 

Abstract not available.  Ryan Seltzer was a contributor on this project but has since left the University of Arizona.

Ryan Seltzer was a contributor on this project but has since left the University of Arizona.

Abstract not available. 

I will obtain publically available data from several studies in different ethnic/racial groups, and use data mining procedures to develop prediction models of type-2 diabetes risk from genetic markers. Career Development - This K01 grant also has a major career development component for which I am taking courses, going to workshops and conferences, and attending research seminars.

Ryan Seltzer was a contributor on this project but has since left the University of Arizona.

This research project was part of my dissertation.  Students who were enrolled in SAFER in the fall semester of 2010 helped by participating in the data collection.

The Jackson Heart Study, JHS, uses community-driven research strategies that promise impact in the near and the long term as a response to American health disparities. This research includes scientific investigations in the tradition of Framingham and other large-scale epidemiologic studies to confirm or revise our understanding of key factors in the current epidemic. The future health of the nation compels us to produce future cohorts of scientists that are prepared to sustain any gains made and to press on toward the long-term goal of eliminating CVD from all segments of American society. The dearth of scientists from the population most afflicted by CVD means that we must make the inclusion of such scientists in the scientific workforce a priority. Through programs described in this issue, the JHS is taking steps toward these goals. Ultimately, the science and the scientists produced by JHS will produce health benefits that transcend geography, ethnicity, and the current era of population research. This study was supported through a subcontract to the University of Mississippi. 

The major goals of this project are to determine whether circulating levels of 25(OH)D or vitamin D intake are related to breast cancer recurrence within the WHEL study. This study was done with the Arizona Cancer Center at the University of Arizona. 

Abstract not available.  Dr. Hu served as PI of subcontract from Harvard University.

This project aims to develop statistical methods to analyze data from colorectal neoplastic prevention trials. This project ended on 6/30/2012.