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Vaccine Study Center

DOR Programming and Analytical Staff

Berwick Chan, BS

Programmer consultant

Bruce Fireman, MA

Biostatistican

Sharareh Modaressi, MD, MPH

Senior data consultant

Karen C. Valdez Nunley, MS

Programmer

G. Thomas Ray, MBA

Senior data consultant

Julius Timbol, BS, MS

Senior data consultant

Arnold H. Yee, MBA

Senior data consultant

Berwick Chan, BS

Berwick Chan has been a programmer/consultant with us since January, 2009. His primary role is to manage data. He has been working in the information technology area for Kaiser Permanente Northern California since 1991. He is the co-architect of OPRSSAV, an online outpatient appointment system used by all Kaiser Permanente facilities in Northern California. He is also the original developer of the registry population database for Chronic Conditions Management (CCM) for Kaiser Permanente Northern California. Before joining Kaiser Permanente, he worked for the U.S. Environmental Protection Agency, the U.S. Navy, Bank of America, and the Computer Science Corporation. He holds a bachelor of science in computer science/software engineering from Sonoma State University, Rohnert Park, CA.

Bruce Fireman, MA

Bruce Fireman is a senior biostatistician and research scientist at the Division of Research, Kaiser Permanente Northern California. His research interests include assessment of the effectiveness and safety of vaccines and drugs, and the costs and outcomes of healthcare delivery systems. He works with population-based data, comparing the effectiveness of alternative treatments and alternative ways of delivering healthcare. He has evaluated disease management programs, Web-based care and primary care teams. He has collaborated with Kaiser Permanente clinicians and administrators in efforts to improve health services.

Sharareh Modaressi, MD, MPH

Sharareh Modaressi joined us in 2016 as a senior data consultant with responsibilities for data analysis using SAS software on various platforms: mainframe, PC and UNIX. Before joining us, she spent more than twelve years of data consulting and analytical experience in Kaiser Permanente Northern California's Quality Operation and Support Department. She is the original developer of GYN model and ICD10 tools for Kaiser Permanente. She has a master of public health from the University of California, Berkeley and a MD degree (with a specialty in infectious disease) from the University of Shahid Beheshti in Tehran/Iran.

Karen C. Valdez Nunley, MS

Karen Nunley joined Kaiser Permanente Vaccine Study Center in 2015 as a senior data consultant with responsibilities for data management and programming using SAS software.  She joined Kaiser Permanente in 2005 within Management Information and Analysis, where she worked on performance reporting, DxCG risk scores, and utilization datasets.  She later joined Charles Schwab as a senior database marketing manager, responsible for retirement participant campaigns.  She returned to Kaiser Permanente in Quality and Operations Support and focused on specialty care access reporting and data analytics.  Karen holds a bachelor's degree in computer science from Ateneo de Manila University, and a master of science in information systems from University of San Francisco.

G. Thomas Ray, MBA

G. Thomas (“Tom”) Ray is a Senior Data Consultant for Kaiser Permanente’s Division of Research and the Kaiser Permanente Vaccine Study Center. He joined the Division of Research in 1995 and his initial collaboration with the Vaccine Study Center involved several studies of the cost-effectiveness of 7-valent pneumococcal conjugate vaccine. The findings from these studies helped inform global decisions regarding the adoption of the pneumococcal vaccine through his membership in, and presentations at, the World Health Organization’s Working Group for Economic Evaluation of Pneumococcal and HIB Vaccines and invited presentations at the 2nd and 3rd Regional Pneumococcal Symposiums. He has subsequently co-authored studies relating to clostridium difficile, herpes zoster, otitis media, influenza, under-vaccination, and the burden of pneumococcal disease, and has lead-authored studies relating to pseudomonas aeruginosa, staphylococcus aureus, skin and soft-tissue infections, and the safety of live-attenuated influenza vaccine.  He holds a BS in economics from the University of Pennsylvania and an MBA from the University of California at Berkeley.

Julius Timbol, BS, MS

Julius Timbol joined us in 2010 as a senior data consultant (vaccine programmer/analyst) with responsibilities for data analysis using SAS software on various platforms: mainframe, PC environment, and UNIX. Before joining us, he spent four years doing SAS programming in Kaiser Permanente Northern California's Quality Operation and Support Department and seven years at CTB/McGraw-Hill programming for psychometricians in educational test designs and analyses, incorporating statistical methods found in item response theory. He enjoys programming statistical or mathematical algorithms. Outside of work, his passions include flying airplanes upside down, participating in aerobatic competitions, and scuba diving. He earned a bachelor of science in mathematics from San Diego State University and a master of science in statistics from California State University, Hayward.

Arnold Yee, MBA

Arnold H Yee, MBA, is a senior data consultant who joined us in mid-2010 to assist investigators in the analysis and data management of high profile pediatric and adult vaccine studies. He has more than 16 years of data consulting and analytical experience in such Kaiser Permanente regional departments as Financial Performance and Quality and Operations Support. He is highly motivated to conduct research on vaccine safety, because it has a direct and immediate impact on public health and policy. He holds a bachelor's from the University of California, Berkeley, and a master of business administration from San Francisco State University.