DrugEpi 3-6 Study Design Exercises Module 3 Introduction Content Area: Analytical Epidemiology Essential Question (Generic): Is there an association between the hypothesized cause and the disease? Essential Question (Drug Abuse Specific): Is there an association between the hypothesized cause and drug use? Enduring Epidemiological Understanding: Causal hypotheses can be tested by observing exposures and diseases of people as they go about their daily lives. Information from these observational studies can be used to make and compare rates and identify associations. Synopsis In Module 3, students explore how hypotheses are tested epidemiologically. Students begin to uncover and develop the following epidemiological concepts and skills: the meaning of the term “association;” the need for a control group; uses of the 2x2 table in calculating risks and relative risks; experimental study design; the importance of ethics in human research; observational study designs used in epidemiology; and the strengths and limitations of each design. Lesson 3-1: Associations and the 2x2 Table Lesson 3-2: Experimental Study - Buprenorphine Example Lesson 3-3: An Actual Randomized Controlled Trial Lesson 3-4: Observational Studies of Natural Experiments - Sensation-Seeking Example Lesson 3-5: Fundamentals of Study Design Lesson 3-6: Study Design Exercises

DrugEpi 3-6 Study Design Exercises Module 3 - Analytical Epidemiology Lesson 3-6 Study Design Exercises Content Reinforcement of study design concepts with an exercise to identify “What is My Design?” An Epi Team challenge that pulls together the study design elements, called “Connections between Designs, Flow Diagrams, and 2x2 Tables” Reinforcement of relative strengths and limitations of each study design with a key exercise that examines “Which Design is Best?” Big Ideas The flow diagrams show how each study design is carried out in time Each study design can be expressed in a 2x2 table format that connects to the depiction in the flow diagram Each study design has strengths, limitations, and trade-offs. Usually, the studies with greater scientific rigor also have higher costs and time to completion. Choice of study designs depends on several circumstances. This project is supported by a Science Education Drug Abuse Partnership Award, Grant Number 1R24DA , from the National Institute on Drug Abuse, National Institutes of Health.

DrugEpi 3-6 Study Design Exercises 1.How is this disease distributed? Health-related conditions and behaviors are not distributed uniformly in a population. They have unique distributions that can be described by how they are distributed in terms of person, place, and time. 2.What hypotheses might explain the distribution of disease? Clues for formulating hypotheses can be found by observing the way a health-related condition or behavior is distributed in a population. 3.Is there an association between the hypothesized cause and the disease? Causal hypotheses can be tested by observing exposures and diseases of people as they go about their daily lives. Information from these observational studies can be used to make and compare rates and identify associations. 4.Is the association causal?Causation is only one explanation for an association between an exposure and a disease. Because observational studies are complicated by factors not controlled by the observer, other explanations also must be considered. 5.What should be done when preventable causes of disease are found? Policy decisions are based on more than the scientific evidence. Because of competing values - social, economic, ethical, environmental, cultural, and political factors may also be considered. Essential QuestionsEnduring Understandings Where are we?

DrugEpi 3-6 Study Design Exercises Controlled Trial Cohort Study Case-Control Cross-Sectional Observational Experimental Review

DrugEpi 3-6 Study Design Exercises Controlled Trial Cohort Study Case-Control Study Cross-Sectional Study Healthy People E Random Assignment E DZ Healthy People E E DZ E E E E E E Review - Flow diagrams of the Four Study Designs

DrugEpi 3-6 Study Design Exercises EPI Team Challenges

DrugEpi 3-6 Study Design Exercises Controlled Trial Healthy People - E Random Assignment E DZ Cohort Study Healthy People - E E DZ Cross-Sectional Study - E E DZ EPI Team Challenge: What’s My Design? Case-Control Study - DZ E E E E

DrugEpi 3-6 Study Design Exercises DZ E E d b c a Flow Diagram 2x2 Table & “fit” Healthy People - E E DZ EPI Team Challenge: Connections Between Flow Diagrams and 2x2 Tables

DrugEpi 3-6 Study Design Exercises Controlled Trial Healthy People - E Random Assignment E DZ Cohort Study Healthy People - E E DZ Cross-Sectional Study - E E DZ EPI Team Challenge: Which Design Is Best? Case-Control Study - DZ E E E E

DrugEpi 3-6 Study Design Exercises EPI Team Challenge - What’s My Design?

DrugEpi 3-6 Study Design Exercises Time Healthy People - E Random Assignment E DZ Controlled Trial Time Healthy People - E E DZ Cohort Study Time DZ E E E E Case-Control Study Time E E DZ Cross-Sectional Study DZ What’s My Design? Controlled Trial Cohort Study Case-Control Study Cross-Sectional Study

DrugEpi 3-6 Study Design Exercises Epidemiologist is involved during the entire time from exposure to disease. Assign treatment and control groups. Follow through time and compare risk of disease in treatment group with risk of disease in control group. Give exposure to treatment group, but not controls. Practice Clue Trial What’s My Design?

DrugEpi 3-6 Study Design Exercises Assign treatment and control groups. Clue 1 Begin Epi Team Challenge Trial What’s My Design?

DrugEpi 3-6 Study Design Exercises Observational Study Flow Diagram DZ - E E E E Clue 2 Case-Control Study What’s My Design?

DrugEpi 3-6 Study Design Exercises Observational Study Flow Diagram Clue 3 Cohort, Case-Control, and Cross-Sectional Studies What’s My Design?

DrugEpi 3-6 Study Design Exercises Observational Study Flow Diagram E E - DZ Clue 4 Cross Sectional Study What’s My Design?

DrugEpi 3-6 Study Design Exercises Follow through time and compare risk of disease in exposed group with risk of disease in the unexposed group. Clue 5 Trial and Cohort Study What’s My Design?

DrugEpi 3-6 Study Design Exercises Healthy People Flow Diagram - Healthy People E E Random Assignment Non-Observational Study Clue 6 Trial What’s My Design?

DrugEpi 3-6 Study Design Exercises Select a group of people with disease and a similar group of people without disease. Clue 7 Case-Control Study What’s My Design?

DrugEpi 3-6 Study Design Exercises E E DZ Flow Diagram Observational Study DZ - Cohort Study What’s My Design? Clue 8

DrugEpi 3-6 Study Design Exercises Epidemiologist is involved during the entire time from exposure to disease. Clue 9 Trial and Cohort Study What’s My Design?

DrugEpi 3-6 Study Design Exercises What’s My Design? Follow through time and compare risk of disease in treatment group with risk of disease in control group. Give exposure to treatment group, but not controls. Trial Clue 10

DrugEpi 3-6 Study Design Exercises Select a study sample. What’s My Design? Trial, Cohort Study, Case-Control Study, and Cross-Sectional Study Clue 11

DrugEpi 3-6 Study Design Exercises Epidemiologist gathers data only at that one point in time. What’s My Design? Cross-Sectional Study Clue 12

DrugEpi 3-6 Study Design Exercises Flow Diagram - DZ What’s My Design? Case-Control Study Clue 13

DrugEpi 3-6 Study Design Exercises DZ Flow Diagram Cohort Study and Trial What’s My Design? Clue 14

DrugEpi 3-6 Study Design Exercises Case-Control Study Epidemiologist is involved after disease has occurred and relies on subjects’ memories to gather information about exposure. Select a group of people with disease and a similar group of people without the disease. Compare percent of exposed people in the two groups. Ask both groups about their exposures in the past. What’s My Design? Clue 15

DrugEpi 3-6 Study Design Exercises Cohort Study Epidemiologist is involved during the entire time from exposure to disease. Select a healthy study sample. Follow through time and compare risk of disease in exposed group to risk of disease in unexposed group. Observe who has and has not been exposed. Clue 16 What’s My Design?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Ask each person about both exposure and disease at that point in time. Epidemiologist gathers data only at that one point in time. Disease risk in exposed group is compared to disease risk in unexposed group. Select a study sample. Clue 17 What’s My Design?

DrugEpi 3-6 Study Design Exercises End Epi Team Challenge What’s My Design?

DrugEpi 3-6 Study Design Exercises Designs, Flow Diagrams, and 2x2 Tables

DrugEpi 3-6 Study Design Exercises DZ E E d b c a Flow Diagram 2x2 Table & “fit” Healthy People - E E DZ EPI Team Challenge: Designs, Flow Diagrams, and 2x2 Tables

DrugEpi 3-6 Study Design Exercises DZ E E a 2x2 Table Where do these people “fit” in the 2x2 table? Flow Diagram Controlled Trial Healthy People E E DZ Random Assignment

DrugEpi 3-6 Study Design Exercises DZ E E b Flow Diagram 2x2 Table Healthy People E E DZ Random Assignment Where do these people “fit” in the 2x2 table? Controlled Trial

DrugEpi 3-6 Study Design Exercises DZ E E c Flow Diagram 2x2 Table Flow Diagram Healthy People E E DZ Random Assignment Where do these people “fit” in the 2x2 table? Controlled Trial

DrugEpi 3-6 Study Design Exercises DZ E E d 2x2 Table Flow Diagram Healthy People E E DZ Random Assignment Where do these people “fit” in the 2x2 table? Controlled Trial

DrugEpi 3-6 Study Design Exercises DZ E E c Flow Diagram 2x2 Table Where are these people in the flow diagram? Cohort Study Healthy People E E DZ

DrugEpi 3-6 Study Design Exercises DZ E E a 2x2 Table Where are these people in the flow diagram? Flow Diagram Cohort Study Healthy People E E DZ Healthy People

DrugEpi 3-6 Study Design Exercises DZ E E d Flow Diagram 2x2 Table Where are these people in the flow diagram? Cohort Study Healthy People E E DZ Healthy People

DrugEpi 3-6 Study Design Exercises DZ E E b Flow Diagram 2x2 Table Where are these people in the flow diagram? Cohort Study Healthy People E E DZ Healthy People

DrugEpi 3-6 Study Design Exercises DZ E E a Where do these people go in the 2x2 table? 2x2 Table Flow Diagram Case-Control Study DZ E E E E

DrugEpi 3-6 Study Design Exercises DZ E E c Where do these people go in the 2x2 table? Flow Diagram 2x2 Table Case-Control Study DZ E E E E

DrugEpi 3-6 Study Design Exercises Flow Diagram DZ E E b 2x2 Table Where do these people go in the 2x2 table? Case-Control Study DZ E E E E

DrugEpi 3-6 Study Design Exercises Flow Diagram DZ E E d 2x2 Table Where do these people go in the 2x2 table? Case-Control Study DZ E E E E

DrugEpi 3-6 Study Design Exercises DZ E E a Flow Diagram 2x2 Table Where do these people go in the 2x2 table? Cross-Sectional Study E E DZ

DrugEpi 3-6 Study Design Exercises DZ E E c Flow Diagram 2x2 Table Where do these people go in the 2x2 table? Cross-Sectional Study E E DZ

DrugEpi 3-6 Study Design Exercises DZ E E d Flow Diagram 2x2 Table Where do these people go in the 2x2 table? Cross-Sectional Study E E DZ

DrugEpi 3-6 Study Design Exercises DZ E E b Flow Diagram 2x2 Table Where do these people go in the 2x2 table? Cross-Sectional Study E E DZ

DrugEpi 3-6 Study Design Exercises End Epi Team Challenge Designs, Flow Diagrams, and 2x2 Tables

DrugEpi 3-6 Study Design Exercises EPI Team Challenge - Which Design is Best?

DrugEpi 3-6 Study Design Exercises Controlled Trial Healthy People - E Random Assignment E DZ Cohort Study Healthy People - E E DZ Cross-Sectional Study - E E DZ EPI Team Challenge: Which Design Is Best? Case-Control Study - DZ E E E E

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Epi Team Challenge Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Cross- Sectional Cohort Case- Control Controlled Trial Epi Team Challenge Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Which study design is the fastest? Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Time Consuming Which study designs are the most time consuming? Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Time Consuming Most Scientifically Sound Which study design is the most scientifically sound? Time Consuming Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Time Consuming Most Scientifically Sound Can Study Rare Diseases Which study design is best for studying rare diseases? Time Consuming Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Time Consuming Most Scientifically Sound Possible Time-Order Confusion Can Study Rare Diseases Which study designs do not identify the time order of exposure and disease? Time Consuming Which Design is Best?

DrugEpi 3-6 Study Design Exercises Cross-Sectional Study Case-Control Study Cohort Study Trial Main WeaknessesMain StrengthsStudy Designs Fastest Time Consuming Most Scientifically Sound Best Measure of Exposure Can Study Rare Diseases Least Expensive Relatively Less Expensive and Relatively Fast Possible Error in Recalling Exposures Most Accurate Observational Study Which Design Is Best? Time Consuming Unethical for Harmful exposures Most Expensive Possible Time-Order Confusion Least Confidence in Findings Good Measure of Exposure It depends …. Which Design is Best?

DrugEpi 3-6 Study Design Exercises It depends... regulations time urgency how much is known about the association money whether the exposure is believed to be beneficial... on the situation regarding

DrugEpi 3-6 Study Design Exercises End Epi Team Challenge What Design is Best?

DrugEpi 3-6 Study Design Exercises Final Review - could be a test

DrugEpi 3-6 Study Design Exercises 4 Study Designs 2 nd 3 rd 4 th Weaker Stronger 1 st Randomized Trial Cohort Study Case-Control Study Cross-Sectional Study Which Design Is Best?

DrugEpi 3-6 Study Design Exercises 4 Study Designs 2 nd 3 rd Longest Time Shortest Time 1 st Cross-Sectional Study Case-Control Study Cohort Study Trial Which Design Is Best? 3 rd

DrugEpi 3-6 Study Design Exercises 4 Study Designs 2 nd 3 rd 4 th Most Expensive Least Expensive 1 st Cohort Study Case-Control Study Cross-Sectional Study Case-Control Study Cohort Study Trial Which Design Is Best?

DrugEpi 3-6 Study Design Exercises 4 Study Designs 2 nd 3 rd 4 th Least Accurate Most Accurate 1 st Cohort Study Case-Control Study Cross-Sectional Study Trial Cohort Study Case-Control Study Cross-Sectional Study Which Design Is Best?

DrugEpi 3-6 Study Design Exercises 4 Study Designs 2 nd 3 rd 4 th Least Sound Most Sound 1 st Trial Cohort Study Case-Control Study Cross-Sectional Study Which Design Is Best?

DrugEpi 3-6 Study Design Exercises CDC Does this all make sense to you? There are four basic study designs for testing hypotheses. Each design has a different plan for assessing exposure and disease. The plan for each design can be understood by: 1) thinking of a train ride from exposure to disease, and 2) constructing a flow diagram. Whatever the study design, the assessment of exposure and disease “fits” into a 2x2 table so that a sample’s exposure and disease can be classified, risks calculated, risks compared, and inferences made. Review - Making Sense

DrugEpi 3-6 Study Design Exercises Big Ideas in this Lesson (3-6) Big Ideas The flow diagrams show how each study design is carried out in time Each study design can be expressed in a 2x2 table format that connects to the depiction in the flow diagram Each study design has strengths, limitations, and trade-offs. Usually, the studies with greater scientific rigor also have higher costs and time to completion. Choice of study designs depends on several circumstances. This project is supported by a Science Education Drug Abuse Partnership Award, Grant Number 1R24DA , from the National Institute on Drug Abuse, National Institutes of Health. Re-Cap

DrugEpi 3-6 Study Design Exercises 1. How is this disease distributed? Health-related conditions and behaviors are not distributed uniformly in a population. They have unique distributions that can be described by how they are distributed in terms of person, place, and time. 2. What hypotheses might explain the distribution of disease? Clues for formulating hypotheses can be found by observing the way a health-related condition or behavior is distributed in a population. 3. Is there an association between the hypothesized cause and the disease? Causal hypotheses can be tested by observing exposures and diseases of people as they go about their daily lives. Information from these observational studies can be used to make and compare rates and identify associations. 4. Is the association causal? Causation is only one explanation for an association between an exposure and a disease. Because observational studies are complicated by factors not controlled by the observer, other explanations also must be considered. 5. What should be done when preventable causes of disease are found? Policy decisions are based on more than the scientific evidence. Because of competing values - social, economic, ethical, environmental, cultural, and political factors may also be considered. Essential QuestionsEnduring Understandings Next Lesson

DrugEpi 3-6 Study Design Exercises What hypotheses might explain the distribution of disease? Is there an association between the hypothesized cause and the disease? Causal hypotheses can be tested by observing exposures and diseases of people as they go about their daily lives. Information from these observational studies can be used to make and compare rates and identify associations. Is the association causal?Causation is only one explanation for finding an association between an exposure and a disease. Because observational studies are flawed, other explanations must also be considered. What should be done when preventable causes of disease are found? Individual and societal health-related decisions are based on more than scientific evidence. Because of competing values, social, economic, and political factors must also be considered. Did the disease prevention strategy work? The effectiveness of a strategy can be evaluated by making and comparing rates of disease in populations of people who were and were not exposed to the strategy. Costs, trade-offs and alternative strategies must also be considered Clues for formulating hypotheses can be found by observing the way a health-related condition or behavior is distributed in a population. Next Lesson Essential QuestionsEnduring Understandings How is this disease distributed? 1. Health-related conditions and behaviors are not distributed uniformly in a population. They have unique distributions that can be described by how they are distributed in terms of person, place, and time.