The publications describes various study designs in epidemiology. These study design are tools that researchers use in order to conduct an effective research
Bivariate RegressionRegression analysis is a powerful and comm.docxhartrobert670
Bivariate Regression
Regression analysis is a powerful and commonly used tool in business research. One important step in regression is to determine the dependent and independent variable(s).
In a bivariate regression, which variable is the dependent variable and which one is the independent variable?
· What does the intercept of a regression tell? What does the slope of a regression tell?
· What are some of the main uses of a regression?
Provide an example of a situation wherein a bivariate regression would be a good choice for analyzing data.
Justify your answers using examples and reasoning. Comment on the postings of at least two peers and state whether you agree or disagree with their views.
Types of Regression Analyses
There are two major types of regression analysis—simple and multiple regression analysis. Both types consist of dependent and independent variables. Simple linear regression has two variables—dependent and independent. Multiple regression consists of dependent variable and two or more independent variables.
· How does a multiple regression compare with a simple linear regression?
· What are the various ways to determine what variables should be included in a multiple regression equation?
· Compare and contrast the following processes: forward selection, backward elimination, and stepwise selection.
Justify your answers using examples and reasoning.
Critical Analysis
Critical analysis involves thinking about what you're reading and interpreting it and evaluating it.
Critical analysis of the books, papers, articles, and research that you read for your classes is an important skill. It is also an important skill in the workplace. Generally speaking, when you engage in critical analysis, you do the following things:
Critical Analysis Principles
Example Questions or Statements
Identify and challenge starting assumptions
Questions:
Did the authors base their conclusions on the appropriate facts? Did the author consider the social conditions of the appropriate time period? Did the author use the appropriate resources to adequately address the question?
Example:
The author used widely-held social beliefs in 2007 to explain social changes that occurred in 1910.
Distinguish facts from opinions, and distinguish objectivity from bias
Questions:
Has the author stated the facts from a research study, or did he just give us his opinion? Has the author explained the situation fairly? Did the author allow her personal opinion or involvement to prejudice her explanation and cloud her judgment?
Example:
This drug has been reported to be an effective treatment. However, all the reports come from the company that created and is selling the drug. There are no independent reports from uninvolved parties that support this claim.
Make inferences from the facts
Questions:
What do these findings mean? What are the implications of these findings? Do these findings impact other areas or concepts? Did the author interpret the findings in a reas ...
Excelsior College PBH 321 Page 1 EXPERI MENTAL E.docxgitagrimston
Excelsior College PBH 321
Page 1
EXPERI MENTAL E PIDE MIOLOGICAL STUDIE S
Epidemiologic studies are either observational or experimental. Observational studies, including ecologic,
cross-sectional, cohort, and case-control designs, are considered “natural” experiments, but experimental
studies are considered true experiments. We will spend the next 2 modules discussing these designs.
Before we begin to discuss study designs, we need a brief introduction to a concept that we will spend more
time discussing in later modules -- bias. The definition of bias is:
“Deviation of results or inferences from the truth, or processes leading to such deviation. Any trend in the
collection, analysis, interpretation, publication, or review of data that can lead to conclusions that are
systematically different from the truth.” (Last, J.M., A Dictionary of Epidemiology, 4th ed.)
Epidemiologists are naturally concerned whether the results of an epidemiologic study are biased, since many
important public health decisions are often drawn from epidemiologic research. The severity of the bias, that
is - how much it influences or distorts the results, is related to the study design as well as how information is
analyzed.
Experimental Studies
The defining feature of experimental studies is that the investigator assigns exposure to the study subjects.
Experimental studies most closely resemble controlled laboratory experiments and serve as models for the
conduct of observational studies, thus they are the “gold standard” of epidemiologic research. Experimental
studies have high validity (i.e., less bias), and can identify even very small effects. The most well known type of
experimental study is a randomized trial (sometimes referred to as a randomized controlled trial), where the
investigator randomly assigns exposure to the study subjects. In this type of study, the only expected
difference between the experimental and control groups is the outcome variable being studied.
Experimental designs like the randomized trial can assess both preventive interventions, where a prophylactic
agent is given to healthy or high-risk individual to prevent disease, or can assess effects of therapeutic
treatment, such as those given to diseased individuals to reduce their risk of disease recurrence, or to improve
their survival or quality of life.
Preventive intervention: Does tamoxifen lower the incidence of breast cancer in women with high risk profile
compared to high risk women not given tamoxifen?
Therapeutic intervention: Do combinations of two or three antiretroviral drugs prolong survival of AIDS
patients as well as regimens of single drugs?
The investigator can assign exposures (or allocate interventions) to either individuals or to an entire
community.
Individual-level assignment: Do women with stage I breast cancer given a lumpectomy alone survive as long
without recurrence of disease as women given a lumpec ...
The publications describes various study designs in epidemiology. These study design are tools that researchers use in order to conduct an effective research
Bivariate RegressionRegression analysis is a powerful and comm.docxhartrobert670
Bivariate Regression
Regression analysis is a powerful and commonly used tool in business research. One important step in regression is to determine the dependent and independent variable(s).
In a bivariate regression, which variable is the dependent variable and which one is the independent variable?
· What does the intercept of a regression tell? What does the slope of a regression tell?
· What are some of the main uses of a regression?
Provide an example of a situation wherein a bivariate regression would be a good choice for analyzing data.
Justify your answers using examples and reasoning. Comment on the postings of at least two peers and state whether you agree or disagree with their views.
Types of Regression Analyses
There are two major types of regression analysis—simple and multiple regression analysis. Both types consist of dependent and independent variables. Simple linear regression has two variables—dependent and independent. Multiple regression consists of dependent variable and two or more independent variables.
· How does a multiple regression compare with a simple linear regression?
· What are the various ways to determine what variables should be included in a multiple regression equation?
· Compare and contrast the following processes: forward selection, backward elimination, and stepwise selection.
Justify your answers using examples and reasoning.
Critical Analysis
Critical analysis involves thinking about what you're reading and interpreting it and evaluating it.
Critical analysis of the books, papers, articles, and research that you read for your classes is an important skill. It is also an important skill in the workplace. Generally speaking, when you engage in critical analysis, you do the following things:
Critical Analysis Principles
Example Questions or Statements
Identify and challenge starting assumptions
Questions:
Did the authors base their conclusions on the appropriate facts? Did the author consider the social conditions of the appropriate time period? Did the author use the appropriate resources to adequately address the question?
Example:
The author used widely-held social beliefs in 2007 to explain social changes that occurred in 1910.
Distinguish facts from opinions, and distinguish objectivity from bias
Questions:
Has the author stated the facts from a research study, or did he just give us his opinion? Has the author explained the situation fairly? Did the author allow her personal opinion or involvement to prejudice her explanation and cloud her judgment?
Example:
This drug has been reported to be an effective treatment. However, all the reports come from the company that created and is selling the drug. There are no independent reports from uninvolved parties that support this claim.
Make inferences from the facts
Questions:
What do these findings mean? What are the implications of these findings? Do these findings impact other areas or concepts? Did the author interpret the findings in a reas ...
Excelsior College PBH 321 Page 1 EXPERI MENTAL E.docxgitagrimston
Excelsior College PBH 321
Page 1
EXPERI MENTAL E PIDE MIOLOGICAL STUDIE S
Epidemiologic studies are either observational or experimental. Observational studies, including ecologic,
cross-sectional, cohort, and case-control designs, are considered “natural” experiments, but experimental
studies are considered true experiments. We will spend the next 2 modules discussing these designs.
Before we begin to discuss study designs, we need a brief introduction to a concept that we will spend more
time discussing in later modules -- bias. The definition of bias is:
“Deviation of results or inferences from the truth, or processes leading to such deviation. Any trend in the
collection, analysis, interpretation, publication, or review of data that can lead to conclusions that are
systematically different from the truth.” (Last, J.M., A Dictionary of Epidemiology, 4th ed.)
Epidemiologists are naturally concerned whether the results of an epidemiologic study are biased, since many
important public health decisions are often drawn from epidemiologic research. The severity of the bias, that
is - how much it influences or distorts the results, is related to the study design as well as how information is
analyzed.
Experimental Studies
The defining feature of experimental studies is that the investigator assigns exposure to the study subjects.
Experimental studies most closely resemble controlled laboratory experiments and serve as models for the
conduct of observational studies, thus they are the “gold standard” of epidemiologic research. Experimental
studies have high validity (i.e., less bias), and can identify even very small effects. The most well known type of
experimental study is a randomized trial (sometimes referred to as a randomized controlled trial), where the
investigator randomly assigns exposure to the study subjects. In this type of study, the only expected
difference between the experimental and control groups is the outcome variable being studied.
Experimental designs like the randomized trial can assess both preventive interventions, where a prophylactic
agent is given to healthy or high-risk individual to prevent disease, or can assess effects of therapeutic
treatment, such as those given to diseased individuals to reduce their risk of disease recurrence, or to improve
their survival or quality of life.
Preventive intervention: Does tamoxifen lower the incidence of breast cancer in women with high risk profile
compared to high risk women not given tamoxifen?
Therapeutic intervention: Do combinations of two or three antiretroviral drugs prolong survival of AIDS
patients as well as regimens of single drugs?
The investigator can assign exposures (or allocate interventions) to either individuals or to an entire
community.
Individual-level assignment: Do women with stage I breast cancer given a lumpectomy alone survive as long
without recurrence of disease as women given a lumpec ...
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Unit 8 - Information and Communication Technology (Paper I).pdfThiyagu K
This slides describes the basic concepts of ICT, basics of Email, Emerging Technology and Digital Initiatives in Education. This presentations aligns with the UGC Paper I syllabus.
Embracing GenAI - A Strategic ImperativePeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
2. Health Psychology Methods
Health psychologists use various research methods in
their search to learn how psychological factors affect
health.
To answer questions regarding how people cope with
medical procedures or cancer, for example, a
psychologist might observe or ask questions of a large
sample of cancer patients.
3. There are two major categories of research methods in
psychology:
Descriptive and
Experimental
4. Research
Method
Research
Setting
Data
Collection
Method
Strengths Weaknesses
Descriptive
studies
Field or
laboratory
Case studies,
surveys and
interviews,
naturalistic
observation.
In-depth
information
about one
person; often
leads to new
hypotheses;
detects naturally
occurring
relationships
among
variables.
No direct
control over
variables;
subject to bias
of observer;
single cases may
be misleading;
cannot
determine
causality;
correlation may
mask
extraneous
variables.
Experimental
studies
Usually
laboratory
Statistical
comparison of
experimental
and control
groups
High degree of
control over
independent
and dependent
variables;
random
assignment
Artificiality of
laboratory may
limit the
generalizability
of results;
certain variables
cannot be
5. Epidemiology The scientific study of the frequency
distribution, and causes of a particular disease or other
health outcome in a population.
6. Descriptive Studies
How a health psychologist might set about answering
the various health related questions?
Researchers look for answers about the behavior of an
individual or a group of people as it occurs in the
home, at work, or wherever people spend their time.
In such a study, called a Descriptive study, the
researcher observes and records the participants’
behavior in a natural setting, often forming hunches
that are subjected later to more systematic study.
7. Several types of descriptive studies are commonly
used:
case studies,
interviews and
surveys, and
observational studies.
8. Case Studies:
Psychologists study one or more individuals
extensively over a considerable period of time in order
to uncover principles that are true of people in general.
Major advantage is it permits a researcher to gather a
much more complete analysis of the individual than
ordinarily can be obtained in studies involving larger
groups.
9. Case studies are useful in suggesting hypotheses for
further study.
They do have one serious disadvantage: Any given
person may be atypical, limiting the “generalizability”
of the results.
E.g; “Darryl Kile was a professional athlete, wasn’t he?
He didn’t live as long as my grandfather, who never
exercised and was a lifelong cigar smoker”.
10. Surveys
Surveys examine individual attitudes and beliefs in
larger numbers and in much less depth than the case
study.
Self-report measures, research participants are asked
to rate or describe some aspect of their own behavior,
attitudes, or beliefs.
11. Surveys are among the most widely used research tools
in health psychology because:
o Easy to administer,
o require only a small investment of time from
participants, and
o quickly generate a great deal of useful data.
12. E.g; chronic-pain patients may be asked to complete a
questionnaire related to their problem that sheds light
on the effectiveness of previous treatments and the
impact of their condition on their daily functioning.
They are not necessarily accurate.
Survey answers may change with the sequence and
wording of the questions.
13. Another limitation of survey research is that
respondents sometimes answer questions in ways that
they would like to be perceived
or that they believe the investigator expects.
14. Observational Studies :
In observational studies, the researcher observes
participants’ behavior and records relevant data.
Observational studies may be structured or
unstructured.
Those studies that feature structured observations
often take place in the laboratory.
In unstructured observations, referred to as
naturalistic observation, the researcher attempts to be
as unobtrusive as possible in observing and recording
the participants’ behaviors.
15. Experimental Studies
Although descriptive studies are useful, they cannot
tell us about the causes of the behaviors that we
observe.
To pinpoint causal relationships, researchers conduct
experiments.
Experiments are commonly used in health psychology
to investigate the effects of health-related behaviors
(such as exercise, diet, and so on) on an illness (such as
heart disease).
16. Dependent and Independent variables.
Experiments test hypotheses by systematically
manipulating (varying) one or more independent
variables (the “causes”)
looking for changes in one or more dependent
variables (the “effects”)
and controlling (holding constant) all other variables
17. Experiments often involve testing the effects of several
different levels of the independent variable on
different groups.
For example, in an experiment testing the level at
which noise (an independent variable) begins to
cause stress (the dependent variable).
18. Random assignment: Assigning research
participants to groups by chance, thus minimizing
preexisting differences among the groups.
Expectancy effects: A form of bias in which the
outcome of a study is influenced either by the
researcher’s expectations or by the study participants’
expectations.
19. Double-blind study: A technique designed to
prevent observer- and participant expectancy effects in
which neither the researcher nor the participants
know the true purpose of the study or which
participants have each condition.
20. Quasi-Experiments
A quasi-experiment is not a true experiment, however,
because it uses groups that differ from the outset on
the variable under study (the subject variable).
No cause-and-effect conclusions can be drawn.
Does not rely on the random assignment.
Instead subjects are assigned to groups based on non-
random criteria.
Subject group & Comparison group involved.
21. For example:
Suppose that researchers wish to investigate the effect
of exercise on academic achievement.
In a quasi-experiment, the subject variable would be
a sedentary lifestyle, with the group consisting of
students who by their own admission get little or no
exercise.
The comparison group would be students who
exercise regularly.
22. Subject variables commonly used in quasi-experiments
are either impossible or unethical to manipulate such
as age, gender, ethnicity, and socioeconomic status.
23. Developmental research:
A study in which a single group of
people is observed over a long span
of time.
Researchers use two basic research
techniques:
longitudinal studies
cross-sectional
24.
25. a. Longitudinal research:
Used to track participants over
an extended period of time
(such as 5years, 10 years etc.)
People usually hesitate to
become the sample of these
studies due to the long
duration.
26. A single group of individuals is observed over a long
span of time.
This allows information about a person at one age to
be compared with information about the same person
at another age, revealing how this person changed over
time.
27.
28.
29.
30. b. Cross sectional research:
A study comparing representative groups of people of
various ages on a particular dependent variable.
For instance, researchers compared six types of risky
health behaviors (the dependent variables) among 9th
- through 12th grade students in the United States.
31. Involves limited time period and cost as compared to
the longitudinal method.
A challenge in cross-sectional research is to make sure
that the various age groups are similar in other ways,
such as socioeconomic status, that might affect the
characteristic being investigated.
32.
33. Suppose that you are interested in studying age-related
changes in how people cope with stress.
If you choose a cross-sectional approach, you might
interview a sample of, say, 25 adults at each of five ages—
for example 20, 30, 40, 50, and 60 years—and gather
information about the ways in which they handle job
stress, family quarrels, financial problems, and so forth.
On the other hand, if you choose a longitudinal study to
explore the same span of years, you (or, more likely, the
researchers who will continue your study 40 years from
now) would interview a group of 20-year-olds today and
again when they are 30, 40, 50, and 60 years of age.
34. Epidemiological Research
Epidemiologists measure the occurrence of
a particular health outcome in a population,
and then attempt to discover why it is
distributed as it is by relating it to specific
characteristics of people and the
environments in which they live.
In other words (Gradually pinpointing the
cause)
35. Epidemiological Research
Story of John Snow who knew something.
John Snow and Story of Cholera in England
(1848).
Laboriously recorded each death & observed
that death rate was 10 times higher in one
specific area.
In some instances, residents on one side of a
residential street were stricken with the disease
far more often than were their neighbours on
the opposite side of the street.
Eventually pinpointed (Polluted drinking water)
36. Epidemiological
Research
Two water supplying companies
(Patchwork). Residents living on the
same street got their water from two
different companies.
Two groups (Polluted water vs
unpolluted water) based on death
distribution.
A major incident on the intersection of
Cambridge and Broad Street. (500
deaths in 10 days)
Removal of Broad street pump
significantly reduced the death rate.
37. Epidemiological Research
Bacterium responsible for epidemic
was discovered after 30 years.
Main method was the keen
observation and counting the
number of deaths.
In other words (Morbidity): The rate
of disease in a population. Such as
specific illness, injury, or disability in
a given group of people at a given
time.
Mortality: Number of deaths due to a
specific cause, such as heart disease,
in a given group at a given time.
38. Epidemiological Research
Incidence: (also called absolute
risk) refers to the number of new
cases of a disease, infection, or
disability, such as whooping cough,
that occur in a specific population
within a defined period of time.
Prevalence: is defined as the total
number of diagnosed cases of a
disease or condition that exist at a
given time
39. Objectives in Epidemiological
Research
Epidemiologists use several research
methods to obtain data on the
incidence, prevalence, and etiology
(origins) of disease.
Three fundamental objectives:
1. Pinpoint the etiology of a particular
disease in order to generate
hypotheses.
2. Evaluate the hypotheses.
3. Test the effectiveness of specific
preventive health interventions
40. Story of Hypertension in African -
Americans
42.5 percent suffer from
hypertension that contributes to
heart disease (Quite a lot
compared to overall US
population i.e. 25%).
One explanation:
Salt retention mechanism
41. Story of Hypertension in African -
Americans
Elevated levels of angiotensinogen II
that directly cause the blood vessels
to constrict hence increasing the
blood pressure.
Pinpointed to Nigeria to Jamaica to
USA.
Only 7 percent of those in rural
Nigeria had high blood pressure,
compared with 26 percent of black
Jamaicans and 33 percent of black
Americans.
Other risk factors increase
significantly as well such as BMI,
poor diet, less exercise and stress.
42. Retrospective Studies
Retrospective (looking back in
time)
Retrospective studies (also
referred to as case-control studies)
compare a group of people who have
a certain disease or condition with a
group of people who do not.
Identical to Quasi experimental
43. Retrospective
Story of Kaposi’s Sarcoma & AIDS
Mainly in gay men.
Epidemiologists were able to pinpoint
unprotected anal sex as a common
background factor among the first men
to die from this deadly form of cancer.
This was years before the AIDS virus,
the human immunodeficiency virus
(HIV), was isolated.
44. Prospective
Prospective studies (look forward
in time) to determine how a group of
individuals changes or how a
relationship between two or more
variables changes over time.
Identical to Longitudinal study design.
45. Class Activity
Get into groups randomly
Your task is to create an experimental
design.
Operationalize your concept
Link it with past studies or concept you
have learnt so far (only 1 is fine)
Define your IV and DV
What will you control?
How will you conduct the experiment.
Your population of target, their gender,
SES, location, education and Why?
You have 30 minutes to prepare and
submit
Editor's Notes
Morbidity/Mortality: Outcome measures
Etiology: The scientific study of the causes or origins of specific diseases
attempt to reconstruct the characteristics or conditions that led to the current health status of people who have a particular disease or condition
there is some evidence that alcohol consumption may contribute to breast cancer. In one large prospective study that has followed a multiethnic cohort of 70,033 healthy women in the San Francisco Bay area for more than 20 years, researchers found that women who consumed one to two drinks per were 1.21 times more likely to be diagnosed with breast cancer than were women who did not drink. Among those who consumed three or more drinks a day, the relative likelihood risk rose to 1.38, whereas those who consumed one drink or fewer each day had a relative likelihood risk of only 1.08