- Email: [email protected]
Epidemiology Is an Art
Epidemiology Is an Art Speech Given at the ACE Abraham Lilienfeld Award Ceremony, Tucson, Arizona, September 16, 2008 I thank the American College of Epidemiology for honoring me with the Abraham Lilienfeld Award. I was fortunate to know Abe, although not fortunate enough to have studied under him. He was clearly a giant of modern epidemiology, advancing both the scope and methods of epidemiology. Thus, it is particularly humbling to be honored with an award in his name. I have had the good fortune and privilege of being mentored by great teachers and scientists including Tom Grayston, San-Pin Wang, and Russ Alexander. They recruited me into the field, instilled in me a passion for epidemiology, and drummed into me the need for respecting the integrity of science and maintaining the highest standards in my research and teaching. Over my long career I have had the opportunity to work with exciting, creative colleagues in epidemiology and other fields. Bull sessions with colleagues like Walter Holland, Ralph Frerichs, Zuo-Feng Zhang, Sander Greenland, Lester Breslow, Jacob Brody, and Barbara Visscher in epidemiology, Janis Giorgi and John Fahey in immunology, Stan Rokaw and Don Tashkin in respiratory function, and John Kurtzke and Len Kurland in neurology have honed my thinking and expanded my horizons. Finally, I have had the excitement of working with brilliant students from all over the world, many of whom are now leaders in epidemiology and public health. They have forced me to organize my ideas and challenged my concepts and thinking. I credit them, as I also credit our two sons, with assuring that I maintained my sense of humility and the excitement of recognizing different perspectives. I have had the privilege and advantage of coming into the field of epidemiology at a particularly exciting time in its history. Over the last 50 years great strides have been made in advancing the science of epidemiology. Beginning in the middle of the 20th century the cohort studies by Doll and Hill (1), Wynder and Graham (2), and others (3) revealed the risk for many malignances, as well as heart and lung diseases, related to smoking. Other cohort studies including the Framingham Heart Study (4), the Coronary Heart Disease in Seven Countries study (5) and the High Blood Pressure Detection and Follow-up Program (5) among others identified the key risk factors for heart disease, including high blood pressure and stroke. More recently, the UCLA Population Studies of Chronic Obstructive Respiratory Disease (6, 7) identified the risk for reduced lung function in children, as well as in adults associated with long-term exposure to primary pollutants and photochemical Ó 2009 Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010
oxidants. The Multicenter AIDS Cohort Study has identified risk factors for HIV infection, many of the immunologic changes occurring in response to HIV infection and the effectiveness of antiretroviral therapy (8, 9). I have had the privilege of being involved in a number of these studies. These landmark studies have provided the science base for many evidence-based interventions. Also, in the middle of the 20th century such brilliant biostatisticians as Berkson, Cornfield, and Hill advanced our understanding of factors such as bias, strategies for analysis of case-control studies, how to make rational decisions based on epidemiologic data, and the relevance of sensitivity analysis. Later in the century Miettinen and Rothman spurred our concern with methodologic issues such as significance, effect measures and causation and organized them conceptually as a foundation for epidemiologic research. In the last quarter of the century many other methodologists, including Greenland, Robins, and Maclure, introduced strategies for controlling and analyzing validity problems, including quantitative bias analysis, causal modeling of time-varying data, and case-crossover study designs. These more recent methodologic developments have been paralleled by an influx of data from large-scale collaborative studies as well as from genetic and molecular epidemiology. It has truly been an exciting time to be an epidemiologist. However, I would like to remind ourselves that epidemiology is more than a sciencedit is an art, the art of knowing when and how to apply the various epidemiology strategies and methodologies creatively to answer relevant health questions. Morris summarized the concept by asserting that ‘‘the epidemiologic method is the only way to ask some questions, one way of asking others and no way at all to ask many’’ (Morris, 1973). Thus, the art of epidemiology is to know when epidemiology is the method of choice, when it is not, and how to use it to answer the question. In the introduction to the section on epidemiology in the forthcoming fifth edition of the Oxford Textbook of Public Health (10, 11), I compare doing an epidemiologic study to constructing a memorable Chinese banquet. ‘‘It is not enough to have the finest ingredients and to know the various Chinese cooking methods. The truly great Chinese chef must be able to select the appropriate ingredients and cooking methods to bring out the flavors of each individual dish and, further, must know how to construct the correct sequence of dishes to excite the palate without overwhelming it. They create a memorable banquet by adding their creative genius to the raw ingredients and the established cooking methods.’’ 1047-2797/09/$–see front matter doi:10.1016/j.annepidem.2008.11.004
AEP Vol. 19, No. 4 April 2009: 286–287
Although it is essential to utilize the brilliant technical and methodologic advances in epidemiology made over the last several decades, it is important to also understand and teach the art of identifying problems which can be answered by epidemiology, asking the right questions, utilizing the optimal study design, using the most advanced and appropriate analytic strategies, recognizing the correct interpretation of the data and, finally, the biologic and policy implications of our research. ‘‘These skills make epidemiology more than a methodology. They create the opportunity for creativity and innovation that provides excitement for the practitioner and makes the successful practice of epidemiology an art.’’ It has been an exciting time to be in epidemiology. The years to come will be even more exciting as we face new challenges and new questions and are armed with even better methods and strategies to address them. In conclusion, I would like to thank my wife, Mimi, who has for 45 years buoyed me up when I was down and assured that I did not increase my hat size when I was up. Roger Detels, MD* Department of Epidemiology, University of California School of Public Health, Los Angeles, CA *Address correspondence to: Roger Detels, MD, MS, Distinguished Professor of Epidemiology, Department of Epidemiology, School of Public Health, University of California, Los Angeles, 71-269 CHS, Box 951772, 650 Charles Young Dr., Los Angeles, CA 90095-1772. Tel: (310) 206-2837. Fax: (310) 206-6039. [email protected]
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REFERENCES 1. Doll R, Hill B. Smoking and carcinoma of the lung: a preliminary report. BMJ. 1950;2:739–748. 2. Wynder EL, Graham EA. Tobacco smoking as a possible etiologic factor in bronchiogenic carcinoma: a study of 684 proved cases. J Am Med Assoc. 1950;143:329–336. 3. Kannel WB, Dawber TR, Kagan A, et al. Factors of risk in development of coronary heart disease – six-year follow-up experience: the Framingham Study. Ann Intern Med. 1961;55:33–50. 4. Keys A. Coronary heart disease in seven countries, , Monograph No. 29. New York: American Heart Association; 1970. 5. Hypertension Detection and Follow-up Program Cooperative Group. Five year findings of the Hypertension Detection and Follow-up Program: mortality by race, sex and age. JAMA. 1979;242:3572–3577. 6. Detels R, Tashkin D, Sayre JW, Rokaw SN, Coulson A, Massey FJ Jr, et al. The UCLA Population Studies of chronic obstructive respiratory disease. 9. Lung function changes associated with chronic exposure to photochemical oxidants: a cohort study among never-smokers. Chest. 1987;92: 594–603. 7. Detels R, Tashkin D, Sayre JW, Rokaw SN, Massey FJ Jr, Coulson AH, et al. The UCLA population studies of CORD.X. A cohort study of changes in respiratory function associated with chronic exposure to SOx, NOx, and hydrocarbons. Am J Public Health. 1991;81:350–359. 8. Detels R, Phair JP, Saah AJ, Rinaldo CR, Munoz A, Kaslow RA, et al. Recent scientific contributions to understanding HIV/AIDS from the Multicenter AIDS Cohort Study. J Epidemiol (Japan). 1992;2:S11–S19. 9. Kaslow RA, Ostrow DG, Detels R, Phair JP, Polk BF, Rinaldo CR. The Multicenter AIDS Cohort Study. Rationale, organization, and selected characteristics of the participants. Am J Epidemiol. 1987; 126:310–318. 10. Morris JN (1973). Uses of Epidemiology (3rd edition) Churchill Livingstone, London. 11. Detels R, Beaglehole R, Lansang MA, Gulliford M. Oxford textbook of public health. 5th ed. Oxford (UK): Oxford University Press; in press.
oxidants. The Multicenter AIDS Cohort Study has identified risk factors for HIV infection, many of the immunologic changes occurring in response to HIV infection and the effectiveness of antiretroviral therapy (8, 9). I have had the privilege of being involved in a number of these studies. These landmark studies have provided the science base for many evidence-based interventions. Also, in the middle of the 20th century such brilliant biostatisticians as Berkson, Cornfield, and Hill advanced our understanding of factors such as bias, strategies for analysis of case-control studies, how to make rational decisions based on epidemiologic data, and the relevance of sensitivity analysis. Later in the century Miettinen and Rothman spurred our concern with methodologic issues such as significance, effect measures and causation and organized them conceptually as a foundation for epidemiologic research. In the last quarter of the century many other methodologists, including Greenland, Robins, and Maclure, introduced strategies for controlling and analyzing validity problems, including quantitative bias analysis, causal modeling of time-varying data, and case-crossover study designs. These more recent methodologic developments have been paralleled by an influx of data from large-scale collaborative studies as well as from genetic and molecular epidemiology. It has truly been an exciting time to be an epidemiologist. However, I would like to remind ourselves that epidemiology is more than a sciencedit is an art, the art of knowing when and how to apply the various epidemiology strategies and methodologies creatively to answer relevant health questions. Morris summarized the concept by asserting that ‘‘the epidemiologic method is the only way to ask some questions, one way of asking others and no way at all to ask many’’ (Morris, 1973). Thus, the art of epidemiology is to know when epidemiology is the method of choice, when it is not, and how to use it to answer the question. In the introduction to the section on epidemiology in the forthcoming fifth edition of the Oxford Textbook of Public Health (10, 11), I compare doing an epidemiologic study to constructing a memorable Chinese banquet. ‘‘It is not enough to have the finest ingredients and to know the various Chinese cooking methods. The truly great Chinese chef must be able to select the appropriate ingredients and cooking methods to bring out the flavors of each individual dish and, further, must know how to construct the correct sequence of dishes to excite the palate without overwhelming it. They create a memorable banquet by adding their creative genius to the raw ingredients and the established cooking methods.’’ 1047-2797/09/$–see front matter doi:10.1016/j.annepidem.2008.11.004
AEP Vol. 19, No. 4 April 2009: 286–287
Although it is essential to utilize the brilliant technical and methodologic advances in epidemiology made over the last several decades, it is important to also understand and teach the art of identifying problems which can be answered by epidemiology, asking the right questions, utilizing the optimal study design, using the most advanced and appropriate analytic strategies, recognizing the correct interpretation of the data and, finally, the biologic and policy implications of our research. ‘‘These skills make epidemiology more than a methodology. They create the opportunity for creativity and innovation that provides excitement for the practitioner and makes the successful practice of epidemiology an art.’’ It has been an exciting time to be in epidemiology. The years to come will be even more exciting as we face new challenges and new questions and are armed with even better methods and strategies to address them. In conclusion, I would like to thank my wife, Mimi, who has for 45 years buoyed me up when I was down and assured that I did not increase my hat size when I was up. Roger Detels, MD* Department of Epidemiology, University of California School of Public Health, Los Angeles, CA *Address correspondence to: Roger Detels, MD, MS, Distinguished Professor of Epidemiology, Department of Epidemiology, School of Public Health, University of California, Los Angeles, 71-269 CHS, Box 951772, 650 Charles Young Dr., Los Angeles, CA 90095-1772. Tel: (310) 206-2837. Fax: (310) 206-6039. [email protected]
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REFERENCES 1. Doll R, Hill B. Smoking and carcinoma of the lung: a preliminary report. BMJ. 1950;2:739–748. 2. Wynder EL, Graham EA. Tobacco smoking as a possible etiologic factor in bronchiogenic carcinoma: a study of 684 proved cases. J Am Med Assoc. 1950;143:329–336. 3. Kannel WB, Dawber TR, Kagan A, et al. Factors of risk in development of coronary heart disease – six-year follow-up experience: the Framingham Study. Ann Intern Med. 1961;55:33–50. 4. Keys A. Coronary heart disease in seven countries, , Monograph No. 29. New York: American Heart Association; 1970. 5. Hypertension Detection and Follow-up Program Cooperative Group. Five year findings of the Hypertension Detection and Follow-up Program: mortality by race, sex and age. JAMA. 1979;242:3572–3577. 6. Detels R, Tashkin D, Sayre JW, Rokaw SN, Coulson A, Massey FJ Jr, et al. The UCLA Population Studies of chronic obstructive respiratory disease. 9. Lung function changes associated with chronic exposure to photochemical oxidants: a cohort study among never-smokers. Chest. 1987;92: 594–603. 7. Detels R, Tashkin D, Sayre JW, Rokaw SN, Massey FJ Jr, Coulson AH, et al. The UCLA population studies of CORD.X. A cohort study of changes in respiratory function associated with chronic exposure to SOx, NOx, and hydrocarbons. Am J Public Health. 1991;81:350–359. 8. Detels R, Phair JP, Saah AJ, Rinaldo CR, Munoz A, Kaslow RA, et al. Recent scientific contributions to understanding HIV/AIDS from the Multicenter AIDS Cohort Study. J Epidemiol (Japan). 1992;2:S11–S19. 9. Kaslow RA, Ostrow DG, Detels R, Phair JP, Polk BF, Rinaldo CR. The Multicenter AIDS Cohort Study. Rationale, organization, and selected characteristics of the participants. Am J Epidemiol. 1987; 126:310–318. 10. Morris JN (1973). Uses of Epidemiology (3rd edition) Churchill Livingstone, London. 11. Detels R, Beaglehole R, Lansang MA, Gulliford M. Oxford textbook of public health. 5th ed. Oxford (UK): Oxford University Press; in press.