Dr. Nasir Mustafa Istanbul Gelisim University Epidemiology

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EPIDEMIOLOGY

4.  EPI = Upon
 DEMOS = People
 LOGY= Study of
‘Study of something that affects
the human population’
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5. HIPPOCRATES (400BC): “On Airs, Waters,
and Places” – Hypothesized that disease
might be associated with the physical
environment, including seasonal variation
in illness
JOHN SNOW (1850): Formulated natural
epidemiological experiment to test the
hypothesis that cholera was transmitted by
contaminated water
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7.  DOLL & HILL (1950): Used a case-control
design to describe and test the association
between smoking and lung cancer.
 DAWBER et al. (1955): Used the cohort
design to study risk factors for
cardiovascular disease in the Framingham
Heart Study.
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8.  THE STUDY OF THE OCCURRENCE OF
ILLNESS
Anderson G, quoted in Rothman KJ: Modern
Epidemiology
 THE STUDY OF THE DISTRIBUTION OF
A DISEASE OR A PHYSIOLOGICAL
CONDITION IN HUMAN POPULATIONS
AND OF THE FACTORS THAT INFLUENCE
THIS DISTRIBUTION
Lilienfeld A: in Foundations of Epidemiology
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9.  Study of disease in populations
 Study of patterns, causes and control of
disease in populations
 The branch of medicine that deals with the
study of the causes, distribution, and control
of disease in populations
 The study of the spread of diseases within
and between populations
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10.  Originally epidemiology was used mainly for
the study of the epidemics of infectious
diseases.
 But because of changing disease patterns over
the time, chronic diseases has assumed an
increasing importance.
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11. Disease does not occur at random
Causal and preventive factors can be identified
in population
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12.  concerned with
Patterns of Disease
occurrence in human
populations and
Factors that influence these
patternsTuesday, March 10, 2020 12

13. “THE STUDY OF THE DISTRIBUTION,
DETERMINANTS, AND DYNAMICS OF
HEALTH RELATED STATES AND
EVENTS IN POPULATIONS AND THE
APPLICATION OF THIS STUDY TO
CONTROL OF HEALTH PROBLEMS“
Last JM: A Dictionary of EpidemiologyTuesday, March 10, 2020 13

14.  Epidemiology focuses on the occurrence
of disease among human populations,
 considering changes within populations
over time and
 differences among and between
populations in disease risk
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15. EPIDEMIOLOGY is concerned with
the causes and prevention of human
disease
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16.  Much of our understanding of the links
between
 Sexual practices and AIDS risk
 Smoking and cancer
 Serum cholesterol and coronary heart
disease
 Obesity and mortality risk
 Air pollution and chronic lung disease
originates from epidemiologic studies
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17.  Distribution is concerned with the
frequency and pattern of health events in
a population
 Disease or health is not uniformly
distributed in human populations
 There are variations in the pattern of
distribution of disease occurrence in a
community
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18.  Epidemiology - study these distribution
patterns in the various sub-groups of the
population
 by time (when), place (where) and
person (who is having the disease),
which leads to control or prevent
disease
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19.  Determinants (reasons and causes)
 Any factor, whether event, characteristic,
or other definable entity, that brings
about change in a health condition
 Determinants are the causes and other
factors that influence the occurrence of
disease and other health-related events
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20.  Primary determinant is the causative
agent of the disease or disorder
 In communicable disease it may be
bacteria, virus or parasite
 In case of nutritional disorder it is the
specific nutrient
 In an automobile accident it is the
vehicle
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21.  Secondary determinants include a
multitude of factors that influence the
disease
 Socio-economic factors causing
malnutrition
 Physical environment influencing
causation of respiratory infections
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22. It is a study of distribution (when,
where and who is having the disease)
and determinants (reasons and causes)
of health related events in specified
population and the application of this
study to control of health problems
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23.  To identify the etiology or the cause
of a disease and the risk factors those
increase a person’s risk for a disease
 To determine the distribution and
magnitude of health and disease
problems in human populations
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24.  To study the natural history and
prognosis of disease
 To generate data for planning,
implementation and evaluation of
services for the prevention, control
and treatment of disease
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25. To eliminate or reduce a
health problem and its
consequences and there by
 to promote health and
well-being of society as a
whole
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26.  Etiologic Research
 Diagnostic Research
 Prognostic Research
 Medical Care Research
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27.  Environmental and Occupational
Epidemiology
 Cancer Epidemiology
 Infectious Disease Epidemiology
 Reproductive Health Epidemiology
 Nutritional Epidemiology
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28.  Epidemiology:The unit of study is a defined
population or population at risk
 Clinical medicine:The case or cases
 The clinician - concerned with the disease in
the individual patient or patients
 Epidemiologist determines the disease
pattern in the entire population
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29.  The epidemiologist is concerned with
both the sick and healthy
 Clinician limits his concern to the
diseased only
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30.  Not antagonist to each other
 But - beneficial to each other
 Clinician helps in the diagnosis of cases
included in the group under scrutiny
 Knowledge of causation, prevalence and
prognosis derived from epidemiological
studies help the clinician in the diagnosis
and management of his patients and their
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31. In conducting epidemiologic studies, the
5W’s are used:
 What = health issue of concern
 When = time
 Where = place
 Who = person
 Why/how = causes, risk factors, modes of
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32. A. OBSERVATIONAL
B. INTERVENTIONAL
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33. a. DESCRIPTIVE:
(Case-Reports, Case-Series, Correlational,
Cross-Sectional)
b. ANALYTICAL:
(Case-control and Cohort)
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34. DESCRIPTIVE EPIDEMIOLOGY
Examining the distribution of a
disease in a population,
and observing the basic features of its
distribution
in terms of time, place, and person.
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35. a. Experimental
b. Quasi- Experimental
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