Background

For more than 45 years, the Department of Biostatistics (BIOS), now home to the Center for Occupational Biostatistics and Epidemiology (COBE), has been one of the leading academic centers of occupational and environmental health research in the United States. BIOS faculty have been active in the development and application of biostatistical methods to study potential health effects of workplace exposures in a variety of industrial settings including: man-made vitreous fiber production, steel making, coal mining, refinery and petrochemical operations, copper and zinc smelting, pharmaceutical production, jet engine manufacturing and tungsten carbide production.

Current and former BIOS faculty members who have made significant contributions in occupational and environmental health research include (alpha order): Vincent Arena, Ph.D, Jeanine Buchanich, Ph.D, Laura Cassidy, Ph.D., Joseph Costantino, Dr.P.H., Richard Day, Ph.D., Philip Enterline, Ph.D., Gary Marsh, Ph.D., Sati Mazumdar, Ph.D., Carol Redmond, Sc.D., Howard Rockette, Ph.D., Roslyn Stone, Ph.D. and Ada Youk, Ph.D.

Faculty members in BIOS continue to make important contributions to the development of new statistical methodology and to provide the quantitative component to public health and biomedical research efforts that have had a major impact on the prevention and treatment of disease. BIOS faculty have also pioneered new and innovative statistical methods, computer software and data base systems to refine and facilitate the conduct of these investigations.

Gary M. Marsh, Ph.D., Professor of Biostatistics, has been active in occupational health research in BIOS for more than 30 years, and for many years has directed the Department’s largest occupational health research unit. Dr. Marsh’s research unit currently includes: a Ph.D. level biostatistician (Dr. Ada Youk), a Ph.D. level epidemiologist (Dr. Jeanine Buchanich), two masters level biostatisticians (Mr. Michael Cunningham and Mr. Zb Bornemann), two masters level information/computer scientists (Mr. Michael Lann and Mr. Charles Alcorn), and six technical/clerical support staff including graduate student researchers and two professional interviewers.

Dr. Marsh’s research group has conducted occupational studies to investigate the long-term health effects of exposure to such agents as man-made mineral fibers, formaldehyde, acrylamide, acrylonitrile, arsenic, petrochemicals, aromatic amines and pharmaceuticals. They have also applied their expertise in occupational epidemiological research to environmental epidemiologic studies of communities exposed to industrial pollutants or to hazardous waste site materials. Following is a sample of recent publications in the occupational and environmental health areas:

• Marsh GM, Gula MJ, Youk AO, Buchanich JM, Churg A, Colby TV: Historical Cohort Study of U.S. Man-Made Vitreous Fiber Production Workers. II. Mortality from Mesothelioma. Journal of Occupational and Environmental Medicine 43:757-766, 2001.
• Marsh GM, Buchanich JM, Youk AO: Historical Cohort Study of U.S. Man-Made Vitreous Fiber Production Workers. VI.Respiratory System Cancer SMRs Adjusted for the Confounding Effect of Cigarette Smoking. Journal of Occupational and Environmental Medicine 43:803-808, 2001.
• Marsh GM, Youk AO, Buchanich JM, Cassidy LD, Lucas LJ, Esmen NA, Gathuru I. Pharyngeal Cancer Mortality among Chemical Plant Workers Exposed to Formaldehyde. Toxicology and Industrial Health, 18:257-268, 2002.
• Marsh GM, Cassidy LD: The Drake Health Registry Study: Findings from Fifteen Years of Continuous Bladder Cancer Screening. American Journal of Industrial Medicine, 43:142-148, 2003.
• Marsh GM, Gula MJ, Roggli V, Churg A: The Role of Smoking and Asbestos Exposure in a Questionable Case of Mesothelioma. Industrial Health, 41:332-334, 2003.
• Marsh GM, Youk AO, Buchanich JM, Esmen NA. Mortality Patterns among Workers in a U.S. Pharmaceutical Production Plant. Annals of Epidemiology, 15:112-122, 2005.
• Marsh GM, Gula MJ. Employment as a Welder and Parkinson’s Disease among Heavy Equipment Manufacturing Workers. Journal of Occupational and Environmental Medicine, 48:1031-1045, 2006.
• Marsh GM, Youk AO, Buchanich JM, Cunningham M, Esmen NA, Hall TA, Phillips ML. Mortality Patterns among Industrial Workers Exposed to Chloroprene and Other Substances: I. General Mortality Patterns. Chemico-Biological Interactions 166:285-300, 2007.
• Marsh GM, Youk AO, Buchanich JM, Cunningham M, Esmen NA, Hall TA, Phillips ML. Mortality Patterns among Industrial Workers Exposed to Chloroprene and Other Substances: II. Mortality in Relation to Exposure. Chemico-Biological Interactions 166:301-316, 2007.
• Marsh GM, Youk AO, Buchanich JM, Kant IJ, Swaen G. Mortality among Workers Exposed to Acrylamide: Updated Follow-up. Occupational and Environmental Medicine, 49:82-95, 2007.
• Marsh GM, Youk AO, Buchanich JM, Erdal S, Esmen NA. Work in the Metal Industry and Nasopharyngeal Cancer Mortality among Formaldehyde-Exposed Workers. Regulatory Toxicology and Pharmacology 48:308-319, 2007.

Currently, Dr. Marsh’s group is conducting an historical cohort study of nearly a quarter million jet engine manufacturing workers for the Pratt & Whitney Company, a mortality surveillance system for the Owens Corning Company, and an historical cohort study of pharmaceutical workers for the Eli Lilly Company. The Pratt &Whitney study is a collaborative effort with the Department of Neuro-Oncology within UPMC and the University of Illinois at Chicago. In addition, the group recently began working on the pilot phase of a large, multi-year historical cohort study of workers exposed to tungsten and cobalt that will be funded by the International Tungsten Industry Association. Dr. Marsh’s group is hoping to secure federal and PA State funding for the conduct of the main epidemiology study.

Dr. Marsh’s research group is also involved in basic methodological research related to statistical computing, longitudinal data analysis and quantitative risk assessment. Some of the major contributions in these areas include:

• The development of the Occupational Cohort Mortality Analysis Program (OCMAP, OCMAP/PC, OCMAP-Plus®) for DOS and the latest OCMAP-Plus® for Windows), a specialized software tool for research in occupational epidemiology.
• Marsh GM, Youk AO, Stone RA, Sefcik S, Alcorn C: OCMAP-PLUS, A Program for the Comprehensive Analysis of Occupational Cohort Data. Journal of Occupational and Environmental Health 40:351-362, 1998.
• A standardized risk assessment protocol (SRAP) was developed for use with hazardous waste sites.
• Marsh GM and Day RD. A Model Standardized Risk Assessment Protocol for Use with Hazardous Waste Sites. Environmental Health Perspectives 1991; 90:199-208.
• A web-based computer software tool for the rapid assessment and characterization of environmental risks (RACER) developed as part of the CDC-funded Health Tracking Initiative in the Department of Epidemiology at the UPitt Graduate School of Public Health. This analytic tool is being designed for use by state and local health department officials as well as academic, governmental and private sector researchers. Publications are under preparation.
• A data repository and retrieval system for detailed mortality data provided by the National Center for Health Statistics and the U.S. Census Bureau. This system, called the Mortality and Population Data System (MPDS) is widely used by occupational and environmental health researchers throughout the U.S.
• Improved methods for conducting mortality follow-up in large-scale longitudinal studies.
• Schall LC, Buchanich JM, Marsh GM, Bittner G: Utilizing Multiple Vital Status Tracing Services Optimizes Mortality Follow-Up in Large Cohort Studies. Annals of Epidemiology , 11:292-296, 2001.
• Buchanich JM, Dolan DG, Marsh GM, Madrigano J. Under-Ascertainment of Deaths Using Social Security Records: A Recommended Solution to a Little-Known Problem. American Journal of Epidemiology, 162:193-194, 2005.
• Reanalysis of the National Cancer Institute cohort study of formaldehyde-exposed workers with focus on the adequacy of the exposure-response modeling.
• Marsh GM, Youk AO. Reevaluation of Mortality Risks from Leukemia in the Formaldehyde Cohort Study of the National Cancer Institute. Regulatory Toxicology and Pharmacology, 40:113-124, 2004.
• Marsh GM, Youk AO. Reevaluation of Mortality Risks from Nasopharyngeal Cancer in the Formaldehyde Cohort Study of the National Cancer Institute. Regulatory Toxicology and Pharmacology, 42:275-283, 2005.
• Marsh GM, Youk AO, Morfeld P. Mis-Specified and Non-Robust Mortality Risk Models for Naspharyngeal Cancer in the National Cancer Institute Formaldehyde Worker Cohort Study. Regulatory Toxicology and Pharmacology 47:59-67, 2007.
• A method for imputing missing racial data (persons and person-time) in a large cohort study was created using a model-based iterative allocation algorithm.
• Youk AO, Stone RA, Marsh GM. A Method for Imputing Missing Data in Longitudinal Studies. Annals of Epidemiology 2004; 14:354-361.
• A method to derive exposure profiles of residential exposure by linking estimated historical environmental exposures to smelter emissions with residential histories
• Marsh GM, Stone RA, Esmen NA, Gula MJ, Gause CK, Petersen NJ, Meaney FJ, Rodney S, Prybylski D: A Case-Control Study of Lung Cancer Mortality in Six Gila Basin, Arizona Smelter Towns. Environmental Research 75:56-72, 1997.
• Marsh GM, Stone RA, Esmen NA, Gula MJ, Gause CK, Petersen NJ, Meaney FJ, Rodney S, Prybylski D: A Case-Control Study of Lung Cancer Mortality in Four Rural Arizona Smelter Towns. Archives of Environmental Health 53:15-28, 1998.
• A method for estimating standardized risk ratios in cohort studies using data from proportional mortality studies.
• Marsh GM, Winwood J, and Rao BR: Prediction of the Standardized Risk Ratio Via Proportional Mortality Analysis. Biometrical Journal 29:355-368, 1987.
• Statistical methods for estimating variances of summary mortality measures accounting for multiple competing risk factors
• Rao BR and Marsh GM: Approximate Simultaneous Inferential Procedures for Overall Risk Assessment of Several Competing Risk Factors in Biomedical and Epidemiologic Studies. Journal of Statistical Inference and Planning 18:323-344, 1988.
• Rao BR and Marsh GM: Approximate Variance Formulas and Asymptotic Joint Sampling Distribution of Standardized Risk Ratios in the Presence of Competing Risks in Cohort Studies. Communications in Statistics-Theory and Methods 17:745-777, 1988.
• Rao BR, Marsh GM, and Winwood J: Asymptotic Interval Estimation of Some Cause-Specific Mortality Risk Measures in Epidemiologic Studies. Biometrical Journal 31:461-475, 1989.
• Rao BR, Marsh GM, and Winwood J: Asymptotic Interval Estimation of Some Cause-Specific Mortality Risk Measures in Epidemiologic Studies. Biometrical Journal 31:461-475, 1989.
• Rao BR, Day R, Marsh GM: Estimation of Relative Risks from Individual and Ecological Correlation Studies. Communications in Statistics-Theory and Methods 21:241-268, 1992.

Today, Dr. Marsh’s research group enjoys a national and international reputation as a leading center of occupational health research. Since the early 1980s, the sponsored research projects conducted by Dr. Marsh’s group have generated more than 15 million dollars in sponsored research funds.