Epidemiology 101 Monday and Tuesday, July 9 and 10, 2007 Mark Kaelin, EdD Montclair State University Department of Health and Nutrition Sciences College of Education and Human Services Public Health and Liberal Education Faculty Development Workshop

“They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question.” Ken Bain, What the Best College Teachers Do “They can then use that ability to think about their own thinking … to grasp how other people might learn. They know what has to come first, and they can distinguish between foundational concepts and elaborations or illustrations of those ideas. They realize where people are likely to face difficulties developing their own comprehension, and they can use that understanding to simplify and clarify complex topics for others, tell the right story, or raise a powerfully provocative question.” Ken Bain, What the Best College Teachers Do Epidemiology 101

DZ Epidemiology is … Epidemiology 101

Epidemiology is … … the study of the distribution and determinants of health-related states or events in specified populations and the application of this study to the control of health problems. Epidemiology 101

“… the blending of population thinking and group comparisons in an integrated theory to appraise health-related causal relationships characterizes epidemiology.” Epidemiology is … Epidemiology 101

Top 8 Reasons to Teach / Learn about Epidemiology Empowers students to be scientifically literate participants in the democratic decision-making process concerning public health policy. Empowers students to make more informed personal health-related decisions. Increases students’ media literacy and their understanding of public health messages. Increases students’ understanding of the basis for determining risk. Improves students’ mathematical and scientific literacy. Expands students’ understanding of scientific methods and develops their critical thinking skills. Provides students with another mechanism for exploring important, real world questions about their health and the health of others. Introduces students to an array of career paths related to the public’s health. Epidemiology 101

Top 8 Reasons to Teach / Learn about Epidemiology Empowers students to be scientifically literate participants in the democratic decision-making process concerning public health policy. Empowers students to make more informed personal health-related decisions. Increases students’ media literacy and their understanding of public health messages. Increases students’ understanding of the basis for determining risk. Improves students’ mathematical and scientific literacy. Expands students’ understanding of scientific methods and develops their critical thinking skills. Provides students with another mechanism for exploring important, real world questions about their health and the health of others. Introduces students to an array of career paths related to the public’s health. Epidemiology 101 On the first day of class, “Rather than laying out a set of requirements for students, they usually talk about the promises of the course, about the kinds of questions the discipline will help students answer, or about the intellectual, emotional, or physical abilities that it will help them develop.” Ken Bain, What the Best College Teachers Do On the first day of class, “Rather than laying out a set of requirements for students, they usually talk about the promises of the course, about the kinds of questions the discipline will help students answer, or about the intellectual, emotional, or physical abilities that it will help them develop.” Ken Bain, What the Best College Teachers Do

A rich body of content knowledge about a subject area is a necessary component of the ability to think and solve problems in the domain, but knowing many disconnected facts is not enough. Research clearly demonstrates that teachers’ content knowledge is structured around the major organizing principles and core concepts of the domain, the ‘big ideas.’ These big ideas lend coherence to teachers’ vast knowledge base; help them discern the deep structure of problems; and, on that basis, recognize similarities with previously encountered problems. … teachers’ strategies for thinking and solving problems are closely linked to rich, well-organized bodies of knowledge about subject matter. Their knowledge is connected and organized, and it is “conditionalized” to specify the context in which it is applicable. Epidemiology 101

Epidemiology 101

Enduring Understandings … the big ideas that reside at the heart of a discipline and have lasting value outside the classroom. Epidemiology 101

Identifying Patterns of Health and Disease

Epidemiological Factors PersonPlaceTime Sex Occupation Age SES Residence Events Anatomical Site Geographic Site Year Season Day, etc. Onset Identifying Patterns of Health and Disease

Estimated Prevalence of Recent Illegal Drug Use by Race / Ethnicity: Person Identifying Patterns of Health and Disease

Epidemiological Factors PersonPlaceTime Sex Occupation Age SES Residence Events Anatomical Site Geographic Site Year Season Day, etc. Onset Identifying Patterns of Health and Disease

Place

Identifying Patterns of Health and Disease Place

Identifying Patterns of Health and Disease Place

Epidemiological Factors PersonPlaceTime Sex Occupation Age SES Residence Events Anatomical Site Geographic Site Year Season Day, etc. Onset Identifying Patterns of Health and Disease

Surveillance Identifying Patterns of Health and Disease The ongoing systematic collection, analysis, and interpretation of outcome-specific data for use in planning, implementation, and evaluation of public health practice closely integrated with the timely dissemination of these data to those who need to know.

Epidemiological Factors PersonPlaceTime Sex Occupation Age SES Residence Events Anatomical Site Geographic Site Year Season Day, etc. Onset Identifying Patterns of Health and Disease

1995 Obesity Trends* Among U.S. Adults BRFSS, 1990, 1995, 2005 (*BMI 30, or about 30 lbs overweight for 5’4” person) No Data <10% 10%–14% 15%–19% 20%–24% 25%–29% ≥30%

Enduring Understandings … the big ideas that reside at the heart of a discipline and have lasting value outside the classroom. Epidemiology 101

A hypothesis can be tested by comparing the frequency of disease in selected groups of people with and without an exposure to determine if the exposure and the disease are associated. b d a c E E DZ Epidemiology 101

Time Controlled Trial Time Cohort Study Time Case-Control Study Time Cross-Sectional Study Epidemiology 101 Comparing Exposed and Unexposed Healthy People E Random Assignment E DZ E E E E Healthy People E E DZ E E

Enduring Understandings … the big ideas that reside at the heart of a discipline and have lasting value outside the classroom. Epidemiology 101 Explanations for Associations

What do we mean when we say that there is an association between two things? Associated TiedRelated Linked Things that are associated are linked in some way that makes them turn up together. Epidemiology 101 Explanations for Associations

Things that are associated are linked in some way that makes them turn up together. Epidemiology 101 Study Links Spanking to Aggression Snacks Key to Kids’ TV- Linked Obesity: China Study Depressed Teens More Likely to Smoke Study Links Iron Deficiency to Math Scores Explanations for Associations Suicide Higher in Areas with Guns Study Concludes: Movies Influence Youth Smoking Cause Confounding Bias Chance Reverse Time Order

Diagram 2x2 Table DZ X X ab c d Epidemiology 101

Unobserved Exposure Cocaine Tobacco Alcohol Marijuana Confounder Epidemiology 101

1. Selection Bias Error due to systematic differences in characteristics between those who take part in a study and those who do not. 2. Information Bias A flaw in measuring exposure or outcome data that results in different quality of data between comparison groups. Epidemiology 101

= Population a 25 cards bc d = ab cd Odd # Even # No Marijuana Total Epidemiology 101

Violent Video Games No Violent Video Games Aggression No Aggression Cross Sectional Study Violent Video Games Can Increase Aggression Time Playing violent video games often may well cause increases in aggressive behavior. Violent Video Games Aggression It could be that … highly aggressive individuals are especially attracted to violent video games. Epidemiology 101

Enduring Understandings … the big ideas that reside at the heart of a discipline and have lasting value outside the classroom. Epidemiology 101 Explanations for Associations

Does evidence from an aggregate of studies support a cause-effect relationship? 1. What is the strength of the association between the risk factor and the disease? 2. Can a biological gradient be demonstrated? 3. Is the finding consistent? Has it been replicated by others in other places? 4. Have studies established that the risk factor precedes the disease? 5. Is the risk factor associated with one disease or many different diseases? 6. Is the new finding coherent with earlier knowledge about the risk factor and the m disease? 7. Are the implications of the observed findings biological sensible? 8. Is there experimental evidence, in humans or animals, in which the disease has m been produced by controlled administration of the risk factor? Epidemiology 101

All scientific work is incomplete – whether it be observational or experimental. All scientific work is liable to be upset or modified by advancing knowledge. That does not confer upon us the freedom to ignore the knowledge we already have, or to postpone the action that it appears to demand at a given time. Sir Austin Bradford Hill “The Environment and Disease: Association or Causation?” Proceedings of the Royal Society of Medicine January 14, 1965 Epidemiology 101