An introduction Epidemiology matters: a new introduction to methodological foundations Chapter 1

Epidemiology is the science of understanding the causes and distribution of population health so that we may intervene to prevent disease and promote health. Epidemiology Matters – Chapter 12

Examples of questions epidemiologists ask  What is the incidence of myocardial infarctions between among women born in 1950 in the United States?  What are the causes of myocardial infarctions in this population?  If we were to change population dietary habits, what improvement in myocardial infarction incidence could we affect? Epidemiology Matters – Chapter 13

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 14

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 15

Evolution of epidemiology  Epidemiology is a relatively new as a formal scientific discipline  Practice of conducting epidemiologic studies is not new; ‘counting’ health and disease goes back centuries  Many of design and analytic techniques that we use today arose in response to health concerns during 19 th and 20 th century Epidemiology Matters – Chapter 16

Epidemiology, a beginning  John Graunt – 17 th century - pioneered approaches to tabulating population health and mortality in rates, ratios, and proportions  William Farr – 18 th and 19 th century - developed more sophisticated life table approaches to understanding the force and burden of mortality  John Snow – 19 th century - used epidemiologic approaches to understand London cholera epidemic; developed and applied basic measures of disease frequency and occurrence Epidemiology Matters – Chapter 17

Epidemiology history, continued  19 th century – focus on infectious disease  20 th century – high-income countries shifted toward non-communicable diseases  Mid 20 th century – methods formalized (1970s)  Late 20 th century – Miettinen, Rothman, and Greenland - modern epidemiology (1980s) formalized central disciplinary principles Epidemiology Matters – Chapter 18

Current conceptual movements 1.Ecosocial perspective on population health – suggests policies, institutions, and characteristics of context contribute to the shaping of health 2.Life course perspective – determinants of health are distributed across the life course and even before conception Therefore, epidemiology understands causes of population health across levels of influence - from cells to society - and across life course. Epidemiology Matters – Chapter 19

`` Social and Economic Policies Neighborhoods and Communities Institutions Living Conditions Social Relationships Individual Risk Factors Genetic/Constitutional Factors Environment Individual/Population Health Pathophysiologic pathways Lifecourse Kaplan, G. What’s wrong with social epidemiology, and how can we make it better? Epid Rev 2004; 26: An ecosocial framework

A lifecourse approach to health production Uauy, R. et al. Diet, nutrition, and the life-course approach to cancer prevention. J Nutr 2005; 135: 2934S-2945S

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 112

Our approach to teaching epidemiology  We are interested in an epidemiology of consequence, an epidemiology that can guide the improvement of the health of population  Therefore, we focus here on teaching underlying concepts that start from understanding populations, and lead the learner through the key steps to designing an epidemiologic study  We will mention and adopt the labels that are used in many other epidemiology textbooks (e.g., confounding) but only after we have introduced the reader to the underlying concepts Epidemiology Matters – Chapter 113

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 114

Epidemiology of consequence, seven steps 1.Define the population of interest 2.Conceptualize and create measures of exposures and health indicators 3.Take a sample of the population 4.Estimate measures of association between exposures and health indicators of interest 5.Rigorously evaluate whether the association observed suggests a causal association 6.Assess the evidence for causes working together 7.Assess the extent to which the result matters, is externally valid, to other populations Epidemiology Matters – Chapter 115

Epidemiology of consequence, seven steps Descriptive epidemiology  Step 1. Define the population of interest  Step 2. Conceptualize and create measures of exposures and health indicators  Step 3. Take a sample of the population  Step 4. Estimate measures of association between exposures and health indicators of interest Assessing for causal effect  Step 5. Rigorously evaluate whether the association observed suggests a causal association Conceptualizing and testing for interactions  Step 6. Assess the evidence for causes working together  Step 7. Assess the extent to which the result matters (is externally valid) to other populations Epidemiology Matters – Chapter 116

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 117

Farrlandia  Examples often based on hypothetical geographic area, Farrlandia  Inspired by William Farr, pioneering epidemiologist and statistician  Through use of Farrlandia examples, students will focus on applying foundational concepts to populations Epidemiology Matters – Chapter 118

1.Evolution of epidemiology 2.Our approach to teaching epidemiology 3.Seven steps to conduct an epidemiologic study 4.Farrlandia 5.Summary Epidemiology Matters – Chapter 119

Summary  This book aims to provide learners with a systematic grounding in the theoretical underpinnings of epidemiology with an awareness of the practical considerations that are essential for public health professionals  This text establishes a foundation by building on methodological innovation and teaching of the previous century, while adopting a novel approach to teaching epidemiologic foundations Epidemiology Matters – Chapter 120

epidemiologymatters.org 21Epidemiology Matters – Chapter 1