Transcript Document

Module 2 Introduction
Context
Content Area: Hypothesis Generation
Essential Question (Generic): What hypotheses might explain the distribution of healthrelated events or states?
Essential Question (Drug Abuse Specific): What hypotheses might explain drug abuse?
Enduring Epidemiological Understanding: Clues for formulating hypotheses can be found
by observing the way a health-related condition or behavior is distributed in a population.
Synopsis
In Module 2, students explore how descriptive epidemiological information on person,
place, and time (PPT) are used to generate hypotheses to explain “why” a health-related
event or state has occurred. Students begin to uncover and develop the following
epidemiological concepts and skills: evaluating PPT information; developing hypotheses
to explain that distribution; understanding that there may be more than one credible
hypothesis; and recognizing when a particular hypothesis does NOT explain the PPT
information.
Lesson 2-1:
Lesson 2-2:
Lesson 2-3:
Lesson 2-4:
Lesson 2-5:
Overview of PPT and What’s My Hypothesis?
In the News
Drug Abuse by “Person” Race / Ethnicity
Drug Abuse by “Place” States in USA
Drug Abuse by “Time” Boundary Effect
DrugEpi 2-1 Overview of PPT and In the News
Module 2 - Hypothesis Generation
Lesson 2-1 Overview of PPT
and What’s My Hypothesis?
Content
• Introduction to using person, place, and time (PPT) to describe
how a disease or other health-related condition is described in a population
• Definition of “hypothesis” and explanation of how PPT is used to generate
“educated guesses” based on observation
• Example of a catastrophic event, and another example of an emerging
disease, that illustrate the usefulness of PPT and provide practice for students
to identify person, place, and time characteristics and generate hypotheses
Big Ideas
• Person, place, and time (PPT) describes a disease or other health-related
condition in terms of “who, where, and when”
• Hypotheses that are suggested by PPT try to explain “why” a disease is
distributed as it is
• PPT information often leads to more than one reasonable hypothesis
This project is supported by a Science Education Drug Abuse Partnership Award, Grant Number 1R24DA016357-01,
from the National Institute on Drug Abuse, National Institutes of Health.
DrugEpi 2-1 Overview of PPT and In the News
Where are we?
Essential Questions
Enduring Understandings
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.
DrugEpi 2-1 Overview of PPT and In the News
Review - Definition of Epidemiology
“… the study of the distribution and determinants
of health-related states or events in specific
populations and the application of this study to the
control of health problems.”
DrugEpi 2-1 Overview of PPT and In the News
Review - the Descriptive Part of Epidemiology
“… the study of the distribution and determinants
of health-related states or events in specific
populations and the application of this study to the
control of health problems.”
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
Epidemiologic studies that are concerned with
characterizing the amount and distribution of health
and disease within a population.
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
PPT Sheet
Person:
Place:
Time:
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
PPT Sheet
Person:
Place:
Time:
DrugEpi 2-1 Overview of PPT and In the News
Definition of Hypotheses
An educated guess
An unproven idea,
based on observation or reasoning,
that can be supported or refuted
through investigation
DrugEpi 2-1 Overview of PPT and In the News
Definition of Hypothesis
Hypothesis
An unproven idea, based on
observation or reasoning, that can
be supported or refuted
through investigation
An educated guess
DrugEpi 2-1 Overview of PPT and In the News
Hypothesis Generation
2. Hypothesis Generation
2. What hypotheses might explain
the distribution of disease?
2. What hypotheses might explain
the distribution of drug abuse?
DrugEpi 2-1 Overview of PPT and In the News
Person, Place, and Time (PPT)
How is the disease or other health condition distributed?
Who?
Where?
When?
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
Person (Who?)
Place (Where?)
Time (When?)
Sex
Residence
Era
Age
Occupation
Year
Ethnicity
Being at Specific Events
Season
Occupation
Geographic Sites
Day, Hour, etc.
Economic Group
Date of Onset
Duration
DrugEpi 2-1 Overview of PPT and In the News
Practice int Hypothesis Generation
SES
DrugEpi 2-1 Overview of PPT and In the News
Practice in Hypothesis Generation
SES
DrugEpi 2-1 Overview of PPT and In the News
Practice in Hypothesis Generation
SES
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
SES
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
DrugEpi 2-1 Overview of PPT and In the News
Descriptive Epidemiology
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
A Mysterious Ailment
By Jerry Bishop, Staff Reporter of the Wall Street Journal
A mysterious, often fatal illness is breaking out in epidemic proportions among
young homosexual men and drug users. More than 180 cases of the strange illness
have been reported since last summer to the federal Center for Disease Control in
Atlanta. As of last Friday, at least 74 of the victims have died. All the victims are
men and 90% of them are either homosexual or bisexual. Many of the victims are
drug users. The illness is characterized by months of fever, malaise, and drastic
weight loss. In almost all cases the patients develop overwhelming infections of one
or more of a dozen different viruses, bacteria or protozoa. The infecting microbes
are types that do not ordinarily cause overt human disease. Many of the patients
also develop a rare type of cancer. To the astonishment of medical scientists, most
of the patients appear to have recently developed a defect in their immune systems
that prevents them from fighting off infections. The infections are extremely difficult
to control with antibiotics and antiviral drugs. "We are reasonably confident that this
is, in fact, a new medical problem," said Dr. Harold Jaffe, an epidemiologist on a
new task force organized by the Center for Disease Control to search for the cause
of the illness. In an effort comparable to that launched last year to unravel the
mystery of toxic shock syndrome, the center's task force is trying to find out whether
a new germ has emerged or whether something in the environment has changed to
account for the sudden outbreak of the illness. For example, the task force is
checking into the use of sexual stimulants by the victims on the possibility these
chemicals can impair the immune system and leave the user vulnerable to
infections. Among such stimulants are chemicals that are inhaled. These include
amyl nitrate sold in glass vials, known by the street name "poppers" and isobutyl
nitrate sold as "liquid incense." First hints that some unusual illness was breaking
out came earlier this year when researchers in New York and Los Angeles reported
cases of both a rare kind of pneumonia and a rare cancer called Kaposi's sarcoma
occurring in a few young men. The men were either homosexual or drug users or
both. The disease center alerted doctors and health officials around the country last
summer to the strange ailment. This week's New England Journal of Medicine,
published today, devotes three articles to describing 19 of the patients, six of whom
died. Publishing three lengthy articles on the same illness is unusual for the medical
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Hypotheses
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
Hypotheses
DrugEpi 2-1 Overview of PPT and In the News
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
Hypotheses
… a new germ has emerged ….
… something in the environment ….
… use of sexual stimulants ….
DrugEpi 2-1 Overview of PPT and In the News
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypothesis Generation
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypotheses
Shaking hands caused the mysterious ailment.
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypotheses
Sitting on toilet seats caused the mysterious ailment.
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypotheses
Poppers caused the mysterious ailment.
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypotheses
Using injection needles caused the mysterious ailment.
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
Descriptive Epidemiologic Clues
Person
Place
Time
Young homosexual
men
Drug Users
Large cities
New York
Los Angeles
90% are bisexual
or homosexual
180 cases since last
summer
Months of fever,
malaise and drastic
weight loss
Hypotheses
Mosquito bites caused the mysterious ailment.
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
AIDS
Now No One Is Safe From
DrugEpi 2-1 Overview of PPT and In the News
A Mysterious Ailment
DrugEpi 2-1 Overview of PPT and In the News
Re-Cap
Big Ideas in this Lesson (2-1)
•
Person, place and time (PPT) describes a disease or
other health-related condition in terms of “who, where,
and when”
•
Hypotheses that are suggested by PPT try to explain
“why” a disease is distributed as it is
•
PPT information often leads to more than one
reasonable hypothesis
This project is supported by a Science Education Drug Abuse Partnership Award, Grant Number 1R24DA016357-01,
from the National Institute on Drug Abuse, National Institutes of Health.
DrugEpi 2-1 Overview of PPT and In the News
Next Lesson
DZ exercise
How is the
“disease” (DZ)
distributed?
Why?
DrugEpi 2-1 Overview of PPT and In the News