Core Concepts: CDC Ethics Hypothesis Human subjects Prevalence rate Person, place, and time Surveillance Survey questions Lessons: 1-1 Introduction to Curriculum 1-2 Surveillance 1-3 Patterns and Hypotheses 1-4 Describing Health-Related Behaviors in Youth 1-5 Creating a Surveillance Question 1-6 Respect – Part I 1-7 Surveillance Studies – In Class 1-8 Surveillance Studies – In School Teacher Note: Module 1 Overview Content Area: Descriptive epidemiology, Surveillance, and Hypothesis-Generation Essential Questions: How is the health or disease outcome distributed in terms of person, place, and time? What are some possible explanations for this distribution? Enduring Understanding: Health and disease are not distributed haphazardly in a population. There are patterns to their occurrence that can be identified through surveillance. Analysis of the patterns of health and disease distribution can provide clues for formulating hypotheses about possible causes. New Lesson 1-3: Patterns and Hypotheses Revised Oct 22,

2 Teacher Note: Enduring Epidemiological Understandings for the Epidemiology and the Energy Balance Equation Curriculum New Lesson 1-3: Patterns and Hypotheses 1.Health and disease are not distributed haphazardly in a population. There are patterns to their occurrence that can be identified through surveillance. Analysis of the patterns of health and disease distribution can provide clues for formulating hypotheses about their possible causes. 2.Causal hypotheses can be tested by conducting investigations of the exposures and outcomes of selected groups of people as they go about their lives. Information from these observational studies can be used to determine if an exposure and an outcome are associated. Because observational studies are complicated by factors not controlled by the observer, other explanations also must be considered.

3 Teacher Note: Authentic Assessment for Module 1 of the Epidemiology and the Energy Balance Equation Curriculum Students will conduct and interpret a descriptive epidemiological survey among students in their class and again among students outside their class. Working in teams, students will have the opportunity to demonstrate their abilities to request informed consent, ask questions about a health-related behavior, accurately record responses, calculate prevalence of the behavior, make accurate statements about the prevalence of the behavior among their classmates, look for patterns, and formulate hypotheses based on the patterns they observe. Deliverables will include either written reports or presentations about the surveys. Specific performance criteria will be used to help ensure that the experiences allow a genuine, realistic, and fair assessment of students’ comprehension of the Module 1 Enduring Epidemiological Understanding. New Lesson 1-3: Patterns and Hypotheses

4 Teacher Note: Photos of Worksheets for Lesson c1-3d 1-3b New Lesson 1-3: Patterns and Hypotheses 1-3a (Optional)

5 Start of Lesson 1-3 (estimate 2 class periods) New Lesson 1-3: Patterns and Hypotheses 5

Big Ideas in Lesson 1-2 Surveillance is a tool used in descriptive epidemiology Review New Lesson 1-3: Patterns and Hypotheses 6 Surveillance is the systematic, ongoing collection, and analysis of data and the timely communication of the information to those who need to know so that action can be taken The Youth Risk Behavior Surveillance System (YRBSS) is an important surveillance mechanism for monitoring patterns in US youth The rationale for the YRBSS is that there are several kinds of health behaviors that increase health risks to youth, and that these should be monitored

7 Understanding the Data in Surveillance Reports From all the answers to the question, patterns can be uncovered. What do we mean by a pattern? New Lesson 1-3: Patterns and Hypotheses A surveillance result comes from asking many people a question about a certain health behavior or health effect. 7

8 Pattern Consistent, characteristic form Who gets sick, and who does not, is not due to chance. There are interesting patterns to who gets sick and who does not. Surveillance studies examine these patterns. Sometimes the results of surveillance provide clues about why some people get sick and others do not. New Lesson 1-3: Patterns and Hypotheses 8

9 Your surveillance question is: “Are you wearing glasses?” Patterns in the Class New Lesson 1-3: Patterns and Hypotheses How many answer yes? How many answer no? What is the pattern? How can we express that pattern in numbers? 9 These are 4 alternate slides if your students wear uniforms – if no uniforms, skip to slide 13 How many answer yes? How many answer no? What is the pattern?

10 Numbers – Using Prevalence Observed patterns can be expressed as prevalence What is prevalence? o The number affected (wearing glasses) What is a prevalence rate? New Lesson 1-3: Patterns and Hypotheses Whole Class Yes – Glasses Total # # # No – Glasses Prevalence Rate of Wearing Glasses ____% o The number affected the total number in the population (# wearing glasses # in class) ÷ ÷ 10 These are 4 alternate slides if your students wear uniforms – if no uniforms, skip to slide 13

In This Example... The numerator is the number of people in the population or sample who experienced the outcome or effect, in this case, wearing glasses. The denominator is the total number of people in the population or sample, in this case, total number of students in the class. total # of students in the class today # wearing glasses New Lesson 1-3: Patterns and Hypotheses 11 These are 4 alternate slides if your students wear uniforms – if no uniforms, skip to slide 13

Express It In Numbers – Pictorial Example The number of students who are wearing glasses All the students in the class Numerator Denominator 12 New Lesson 1-3: Patterns and Hypotheses These are 4 alternate slides if your students wear uniforms – if no uniforms, skip to slide 13

13 Your surveillance question is: “Are you wearing blue?” Patterns in the Class New Lesson 1-3: Patterns and Hypotheses How many answer yes? How many answer no? What is the pattern? How can we express that pattern in numbers? 13 Use these 4 slides (13-16) instead of slides if your students do not wear uniforms

14 Numbers – Using Prevalence Observed patterns can be expressed as prevalence What is prevalence? o The number affected (wearing blue) What is a prevalence rate? New Lesson 1-3: Patterns and Hypotheses Whole Class Yes – Blue Total # # # No – Blue Prevalence Rate of Wearing Blue ____% o The number affected the total number in the population (# wearing blue # in class) ÷ ÷ 14 Use these 4 slides (13-16) instead of slides if your students do not wear uniforms

In This Example... The numerator is the number of people in the population or sample who experienced the outcome or effect, in this case, wearing blue. The denominator is the total number of people in the population or sample, in this case, total number of students in the class. total # of students in the class today # wearing blue New Lesson 1-3: Patterns and Hypotheses 15 Use these 4 slides (13-16) instead of slides if your students do not wear uniforms

Express It In Numbers – Pictorial Example The number of students who are wearing blue All the students in the class Numerator Denominator 16 New Lesson 1-3: Patterns and Hypotheses Use these 4 slides (13-16) instead of slides if your students do not wear uniforms

17 Surveillance Notebook New Lesson 1-3: Patterns and Hypotheses Worksheet 1-3a: Practice in Prevalence Calculations Everyone in the Class Yes Total # # # No Prevalence Rate _____% 17 What are you curious about? What is the prevalence of... ? Cereal for Breakfast? Other Behaviors? Walking to School?

Express It In Numbers – More Practice The number of students who had cereal for breakfast All the students in the class Numerator Denominator 18 New Lesson 1-3: Patterns and Hypotheses

Express It In Numbers – More Practice The number of students who walked to school today All the students in the class Numerator Denominator 19 New Lesson 1-3: Patterns and Hypotheses

Express It In Numbers – More Practice The number of students who …? All the students in the class Numerator Denominator 20 New Lesson 1-3: Patterns and Hypotheses

21 Possible break point between class periods New Lesson 1-3: Patterns and Hypotheses

22 Patterns in Watching Television Consistent, characteristic form? New Lesson 1-3: Patterns and Hypotheses 22

23 “Nationwide, 32.8% of students watched television 3 or more hours per day on an average school day.” Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5. Patterns in Watching Television Overall Prevalence New Lesson 1-3: Patterns and Hypotheses 23

24 “Overall, the prevalence of having watched television 3 or more hours per day was higher among black (55.5%) and Hispanic (41.9%) than white (24.8%) students;”... Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5. Patterns New Lesson 1-3: Patterns and Hypotheses 24

25 “Overall, the prevalence of having watched television 3 or more hours per day was higher among 9th-grade (35.2%) and 10th-grade (34.7%) than 11th-grade (30.8%) and 12th-grade (29.7%) students;” Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5. Patterns New Lesson 1-3: Patterns and Hypotheses 25

26 “... higher among 9th-grade female (33.9%) and 10th- grade female (33.6%) than 11th-grade female (29.6%) students; and higher among 9th-grade male (36.3%) and 10th-grade male (35.7%) than 11th-grade male (31.8%) and 12th-grade male (28.4%) students.” Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5. Patterns New Lesson 1-3: Patterns and Hypotheses 26

27 Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5. Worksheet 1-3b: Reading a Data Table and a Graph New Lesson 1-3: Patterns and Hypotheses 27 Surveillance Notebook

28 CategoryFemaleMaleTotal Race/Ethnicity White Black Hispanic Grade Total Percentage of High School Students Who Watched 3 or More Hours/Day* of Television, by Sex, Race/Ethnicity, and Grade, 2009** * On an average school day ** Morbidity and Mortality Weekly Report (MMWR) Youth Risk Behavior Surveillance – United States, Centers for Disease Control and Prevention. June 4, Vol. 59 SS-5.

29 Reading a Graph New Lesson 1-3: Patterns and Hypotheses 29

30 Study Patterns of Person, Place & Time Who? Where? When? Person: Place: Time: New Lesson 1-3: Patterns and Hypotheses 30

31 Descriptive Epidemiologic Factors PersonPlaceTime Trends (changes over time) Age Sex Race Ethnicity Occupation Socioeconomic Status Marital Status Country State Urban/Rural Neighborhood Residence Geography Small to Large Increments of Time (such as Hours, Days/Weeks, Months, Seasons, Years, Decades) New Lesson 1-3: Patterns and Hypotheses 31

32 Hypothesis Patterns Health and disease are not distributed haphazardly in a population. There are patterns to their occurrence that can be identified through surveillance. Analysis of the patterns of health and disease distribution can provide clues for formulating hypotheses about their possible causes. New Lesson 1-3: Patterns and Hypotheses 32

33 Hypotheses An educated guess An unproven idea, based on observation or reasoning, that can be supported or refuted through investigation A tentative explanation New Lesson 1-3: Patterns and Hypotheses 33

34 Surveillance Notebook Worksheet 1-3c: Reading Assignment: Hypotheses about Overweight and Obesity New Lesson 1-3: Patterns and Hypotheses 34

35 What are the hypotheses put forth in the article? Patterns and Hypotheses New Lesson 1-3: Patterns and Hypotheses 35

Big Ideas in Lesson 1-3 Prevalence is the percentage of a whole group that has the health-related behavior or effect of interest Person, place, and time (PPT) information tells us how a health-related behavior or effect is distributed Hypotheses are educated guesses that try to explain the distribution Health-related articles often provide PPT clues and educated guesses PPT information can be expressed in sentences, in tables, or on graphs Re-Cap 36 New Lesson 1-3: Patterns and Hypotheses

37 Surveillance Notebook Worksheet 1-3cd Descriptive Epidemiology of Obesity / Physical Activity New Lesson 1-3: Patterns and Hypotheses 37 OPTIONAL additional class

38 Ways that Patterns of Obesity Could Be Described Looking for Patterns Ways that Patterns of Physical Activity Could Be Described New Lesson 1-3: Patterns and Hypotheses 38