Investigation 5-2 Did the prevention strategy work? xxxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxx Detectives in the Classroom – Investigation 5-2: How to Evaluate How to Evaluate

Investigation How is this disease distributed? Hypotheses 2 Is there an association? 3 Is the association causal? 4 What should be done to prevent the disease? Did the exposure and the disease turn up together? Why did the exposure and the disease turn up together? What’s my hypothesis? 5 Did the prevention strategy work? Was is worth the effort? Should we continue it? What should I do? What should society do? Where are we and where are we going? Detectives in the Classroom – Investigation 5-2: How to Evaluate

Investigation 5-2 Random Assignment - E E DZ Healthy People Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Trial Review

Investigation E E DZ Healthy People Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Cohort Study Review

Investigation DZ E E E E Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Case-Control Study Review

Investigation DZ E E Review Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Cross- Sectional Study

Investigation 5-2 Epi Talk Risk Management Steps taken to reduce the levels of risk to which an individual or a population is exposed. Detectives in the Classroom – Investigation 5-2: How to Evaluate Review

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes”

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” GroupInterventionDescription % Developed Diabetes Lifestyle Intervention Participants received intensive training in diet, exercise, and behavior modification skills aimed at reducing weight by 7% through a low-fat diet and exercising for 150 minutes a week. 14% Metformin & Information Participants received treatment with the drug metformin (850 mg twice a day) and received information on diet and exercise. 22% Placebo & Information Participants received placebo pills, in place of metformin, and received information on diet and exercise. 29%

Investigation 5-2 Epi Teams Detectives in the Classroom – Investigation 5-2: How to Evaluate

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes”

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” Random Assignment - E E DZ Healthy People Trial Time E E DZ Healthy People Cohort Study Time DZ E E E E Case-Control Study Time DZ E E Cross- Sectional Study Time

Investigation 5-2 Epi Talk Random Assignment Assignment of individuals to groups by chance. Detectives in the Classroom – Investigation 5-2: How to Evaluate Epi Talk Random assignment should make the groups similar at the start of the study. Random assignment should not be confused with haphazard assignment.

Investigation 5-2 Epi Talk Placebo An inactive medication or procedure. Detectives in the Classroom – Investigation 5-2: How to Evaluate Epi Talk In a trial, placebos are given to the control group. Because a placebo is an inactive medication or procedure, it means “no exposure.”

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” 2

Investigation 5-2 Lifestyle Intervention Random Assignment - 3,234 people at high risk for type 2 diabetes Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Trial 14% DZ Metformin & Information 22% DZ Placebo & Information 29% DZ

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” Type 2 diabetes “… is strongly associated with obesity (more than 80% of people with type 2 diabetes are overweight), inactivity, family history of diabetes, and racial or ethnic background.” 4

Investigation 5-2 Obesity Type 2 Diabetes Total 100 % b d a c Type 2 Diabetes Risks Relative Risk % CompareCountDivide times as likely Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” No Type 2 Diabetes No Obesity

Investigation 5-2 Epi Talk External Data Monitoring Board Detectives in the Classroom – Investigation 5-2: How to Evaluate Epi Talk An independent group of experts that periodically reviews and evaluates study data. It is interested in safety of participants, study conduct and progress, and preliminary findings. It can make recommendations about continuation, modification, or termination of the study.

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate “Diet and Exercise Dramatically Delay Type 2 Diabetes” External Data Monitoring Board 5

Investigation 5-2 Detectives in the Classroom – Investigation 5-2: How to Evaluate Ideal Conditions? / Everyday Conditions? Random Assignment - E E DZ Healthy People Trial Time E E DZ Healthy People Cohort Study Time DZ E E E E Case-Control Study Time DZ E E Cross- Sectional Study Time

Investigation E E DZ Healthy People Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Cohort Study Lifestyle Intervention Effectiveness 6

Investigation People at high risk for type 2 diabetes Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Effectiveness: Cohort Study Lifestyle Intervention Type 2 Diabetes DZ No Lifestyle Intervention Type 2 Diabetes DZ

Investigation 5-2 Lifestyle Intervention Effectiveness - DZ E E E E Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Case-Control Study 7

Investigation Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Effectiveness: Case-Control Study People with type 2 diabetes People without type 2 diabetes but at high risk Lifestyle Intervention No Lifestyle Intervention Lifestyle Intervention No Lifestyle Intervention

Investigation 5-2 Lifestyle Intervention Effectiveness Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Cross- Sectional Study 8 DZ E E -

Investigation 5-2 Effectiveness: Cross-Sectional Study Time Detectives in the Classroom – Investigation 5-2: How to Evaluate Cross- Sectional Study - Lifestyle Intervention No Lifestyle Intervention Type 2 Diabetes No Type 2 Diabetes

Investigation E E DZ Time Did the prevention strategy work? Essential Question 5 Detectives in the Classroom – Investigation 5-2: How to Evaluate

Investigation 5-2 CDC Investigation 5-2 has ended. How to Evaluate Detectives in the Classroom – Investigation 5-2: How to Evaluate