Understanding the Numbers: Biostatisticians in Demand

February 15, 2010

Major advances in molecular biology over the past decade have led to the explosive growth of data generated by biomedical researchers. Fueled by the human genome project, which successfully mapped the locations of genes on all 23 chromosomes, scientists are now able to conduct scans of every gene turned on in a cell— as well as every protein created by those genes.  Individual experiments can now generate millions of data points, which require detailed analysis.

In response, new technologies have made it possible to collect and analyze these massive medical data sets. However, processing these data for use in health research requires quantitative skills that few people have.

“Biostatisticians are quickly becoming some of the most highly sought after
researchers in the field of medicine,” says Françoise Seillier-Moiseiwitsch, PhD, chair of the Department of Biostatistics, Bioinformatics and Biomathematics (DBBB).  The Bureau of Labor Statistics recently projected a nine percent growth in the job market for statisticians between 2006 and 2016. The 2008–2009 Occupational Outlook Handbook also notes that a master’s degree is the minimum requirement for most of these jobs.

At Georgetown, the DBBB provides expertise in this field, supporting the research of faculty scientists and offering advanced training for master’s level students and postdoctoral fellows. In addition to teaching and research, the faculty and staff of the biostatistics program provide statistical analysis for a variety of ongoing research projects for the Georgetown Lombardi Comprehensive Cancer Center and the Georgetown University Medical Center (GUMC). Biostatisticians at Lombardi are involved in all levels of research, from the design of clinical trials to analyzing the correlations—or lack thereof— between genes and cancer risk in population studies.

“Our faculty members are passionate about teaching and conducting breakthrough studies on topics including proteomics, functional genomics and cancer control,” says Seillier- Moiseiwitsch. “In 2008, staff logged over 9,000 hours of direct consultation and education, supporting the research of more than 100 Georgetown investigators.”

New Georgetown education programs respond to need
In 2009 the DBBB introduced two new Graduate Certificates in addition to its master’s degree in biostatistics. The one year certificate programs in Biostatistics and Epidemiology feature a mix of quantitative and biomedical science courses. They are designed for working professionals who seek supplementary training in biostatistics and epidemiology, as well as for students who wish to further their knowledge of these fields.

“I believe that the new certificate programs will be especially valuable for those scientists who graduated more than a decade ago and find themselves in need of retooling,” says Seillier-Moiseiwitsch.

The three-semester master’s program in biostatistics has helped GUMC graduates acquire positions in academic research institutions, federal agencies, pharmaceutical companies and the biotechnology industry.  “And we have a number of scientists embedded in labs throughout the research center that have participated in our master’s degree program,” she adds.

With the addition of the certificate programs,the DBBB continues to grow while providing valuable educational resources to the University and the scientific community.  Like the master’s program, the graduate certificate programs will provide integrated, computer-based training in quantitative and biomedical sciences that support healthrelated research in academic, government, and industry settings. Both certificates require completion of 15 core courses including studies in clinical trials, computational software, and statistical inference.

No other curriculum in the Washington metropolitan area offers such a mix of course offerings in a single certificate program. At Georgetown, students also benefit from the presence of the School of Medicine, Lombardi—an NCI designated comprehensive cancer center—and more than 400 biomedical researchers who are part of the Georgetown University Medical Center.

Students reap the benefits
Ping Li with her mentor, Celia Byrne, PhDPing Li, a graduate student in the Department, received a graduate research assistantship that has benefited her both academically and professionally. Li works with Celia Byrne, PhD, an assistant professor of oncology, to analyze data from a study on risk factors for breast cancer.

“Evidence-based epidemiology research is a powerful tool for finding the risk factors for disease,” says Li. “As a woman myself, to be a part of cutting edge research work on breast cancer that can potentially improve or save many women’s lives means a lot to me.”

Byrne studies mammographic breast density—that is, the density of breast tissues as measured by mammograms. Her work has previously shown that denser breast tissue correlates with a higher risk of breast cancer. In a new study, Byrne seeks to understand the factors that cause higher breast density, specifically looking at genetic factors and levels of IGF, a growth factor that is believed to be related to density. Her key research question is whether there is an association between a woman’s genotype and her breast density or IGF levels. From a statistical perspective, Li asks, “How likely is it that a genotype will predict breast density or predict IGF levels?”

Li began working on this project last spring, during her second semester in the Biostatistics Master’s Program. The experience has deeply impressed her. “The people doing research in cancer are really contributing to humankind, but they’re not in the forefront on stage,” says Li. “This really touched me.”

She had been working in data analysis for the Beijing Customs Office, where her work helped identify economic trends for the city. Wanting to gain a deeper understanding of statistics, she applied to Georgetown’s master’s program because of its emphasis on applied research.  “At the beginning, when you look at data, you have no idea what’s behind them,” she says. “I think that’s what is amazing about math—you can show people what the data really mean.”

Working with Byrne, Li began the first step of any biostatistician’s work—“data cleaning.” This breast density study surveyed over 1000 women, each of whom completed a 571-question survey and received a mammogram and blood test for genotyping and measuring IGF levels. For each of the thousand study subjects, Li had more than 1000 variables to cross-check for accuracy.  For example, says Li, subjects sometimes give inconsistent responses. While one answer may indicate that the subject does not smoke, another may say she smokes 3 cigarettes a day. Li uses SAS, specialized biostatistical analysis software, to create a table of all of the conflicting answers. She then returns to relevant surveys to determine if the problem is a data entry error or requires clarification from the study participant.

Li spent the spring semester verifying the data. She then worked with Byrne to determine analysis co-variants. Co-variants are factors not part of the research question that may influence results and must be considered in the analysis. For example, IGF levels can be affected by age, menopausal status, and body mass index. These co-variants are added to the equation, upon which Li’s analysis will be based.

This summer she began her analysis, working closely with Seillier-Moiseiwitsch, who is co-advisor on her thesis. Together, they selected a statistical model to answer Dr. Byrne’s research question. To use this model, Li first had to ensure that the sample of subjects is representative of the wider population—that is, evenly distributed in a bell curve. Li was able to complete the analysis and wrote her thesis in time to graduate in December.

“Working on this project really made me think that what I’m doing helps fight cancer. I’m proud of my work,” says Li.

Learn more about the programs at http://dbbb.georgetown.edu

Author: Claire Cushman and Allison T. Whitney