Epidemiology

Question 1

Study of the distribution of health related conditions in specified populations and the determinants of these health events

Answer 1

ETYMOLOGY

Question 2

Components of Epidemiology

Answer 2

• Study
• Frequency
• Distribution: how many of… who? Where? When?
• Determinants: how? Why?
• Health-Related data V.S. Disease
• Populations/Communities
• Application

Question 3

Applied science, practice, health prevention,
health promotion

Answer 3

Application

Question 4

How does one element influence the occurrence
of the events

Answer 4

Determinants: how? Why?

Question 5

answers the question “how many?” (number of
times the health event occurs)

Answer 5

○ Frequency

Question 6

Father of Western Medicine

Answer 6

Hippocrates

Question 7

Father of Modern Epidemiology
★ Figured out the cause of Cholera breakout in the
past was because of the Broad street pump
handle being used by infected people therefore
spreading the disease (First beginnings of
Epidemiology

Answer 7

John Snow

Question 8

T or F
Today, we use to have this register of infant baptism, so it’s usually the churches or the parishes that have these records of the neighborhood, the community data. in front baptisms would then correlate with the births in the community. and they would also have a census of the people who died
because the people used to bury their dead usually at
the back of the church.

Answer 8

false
in the earlier times we used to have this register of
infant baptism, so it’s usually the churches or the
parishes that have these records of the neighborhood,
the community data. in front baptisms would then
correlate with the births in the community. and they
would also have a census of the people who died
because the people used to bury their dead usually at
the back of the church.

Question 9

pertains to the number of people who are disease
free at the start of data collection. so they can
develop the disease throughout the time that the
data is being collected. But the requirement is
that at the start they do not have the condition.

Answer 9

Population-at-risk

Question 10

★ It is the prerequisite for measuring the frequency

Answer 10

Case definition

Question 11

It means the person bearing the outcome of
interest. If the outcome of interest is the absence
of disease, they can be a case. But, if you want the
outcome of interest to them having a condition,
then there is also a case

Answer 11

CAse

Question 12

★ Describes HOW COMMON an illness (or other
health event) is related to the size of the
population (population-at-risk) and a measure
of time

Answer 12

Measures of disease frequency

Question 13

Purposes of Epidemiological studies

Answer 13

Causation of disease
○ Describing the natural history of disease
★ Includes the disease outcomes (who survives? Who dies?)
○ Describing the health status of the population
○ Evaluating interventions
○ For public health intelligence and public health promotion efforts

Question 14

A type of study where measurements like disease rates and information about exposures are made on a group of people

Answer 14

ECOLOGICAL
STUDIES

Question 15

Describes the
characteristics of a group of people
who have the same disease or the
same exposure

Answer 15

CASE SERIES

Question 16

The aim of the study is to understand the demographics, clinical presentations, prognosis or other characteristics of people who have a particular disease
● It may also describe something unusual
○ early 1980s had an occurrence of an unusual
pneumonia in men which led to the identification of
HIV

Answer 16

CASE SERIES

Question 17

A study that takes a selected population and measure health
information at a given point in time
○ gives a snapshot of their health

Answer 17

CROSS
SECTIONAL

Question 18

It involves asking participants a series of questions using
questionnaires

Answer 18

CROSS
SECTIONAL

Question 19

● These studies are also called this,
because they measure how many
people have a disease at a particular
point in time
● The selected population must be the
representative of the total population

Answer 19

PREVALENCE STUDIES

Question 20

It uses a comparison group called controls who are similar to cases but do not have the disease
○ both groups are asked about their previous exposures to
different risk factors

Answer 20

CASE
CONTROL
STUDY

Question 21

Each of the risk factors the odds of
being exposed if they were a case is
compared to the odds of being
exposed if they were a control this is
called an ODDS RATIO

Answer 21

caswe controol study

Question 22

T or F
An odds ratio of MORE THAN ONE
means that people with the disease are
more likely to have been exposed to
that risk factor than people without
the disease
○ this suggests that it could be a
possible cause of the disease
● An odds ratio of LESS THAN ONE
suggests that it’s a PROTECTIVE
FACTOR

Question 23

● It is the ratio between the risk of
disease in the exposed group
compared to the risk of disease in the
unexposed group

Answer 23

RELATIVE RISK (RR)

Question 24

a well-known cohort study in the
1950s
● This study provided valuable
scientific evidence of the
HARMFUL EFFECTS OF SMOKING
especially the LINK BETWEEN
SMOKING AND LUNG CANCER

Answer 24

BRITISH DOCTOR STUDY

Question 25

ADVANTAGES OF THE COHORT STUDY

Answer 25

time sequence of events can be determined this is useful when trying to determine what caused a disease
information about several different outcomes and risk
factors can be collected at the same time
○ this allows for some analysis to be conducted
on the data

Question 26

DISADVANTAGES OF THE COHORT STUDY

Answer 26

The high cost and they can involve a large number of people
being followed over a long period of time
● They’re generally not suitable to study rare diseases
● Ensuring that people who started the study stay until the end of the study if many people drop out it
will affect the results of the study

Question 27

T or F
In an cognitive study, an
intervention is done on a group of
people and the outcome studied

Answer 27

TRUE
In an interventional study, an
intervention is done on a group of
people and the outcome studied

Question 28

It is the best study design for an
interventional study
● For example, we want to study the
effects of a new drug we start off
with a study population

Answer 28

RANDOMIZED CONTROLLED STUDY

Question 29

A situation where the neither the
participants nor investigators know
which group had the intervention

Answer 29

DOUBLE BLINDING

Question 30

ADVANTAGES OF THE RANDOMIZED CONTROL
STUDIES

Answer 30

t can provide good evidence that the
intervention led to an outcome
● Randomization ensures that both
groups have an equal chance of
receiving the intervention and that
they have similar characteristics this
way the effect of the intervention can
be determined without other factors
influencing the outcome

Question 31

DISADVANTAGES OF THE RANDOMIZED
CONTROL STUDIES

Answer 31

Generally quite expensive to do
● it may also require a large number of
participants
● It is not always possible due to it
having the possibility of being
unethical

Question 32

T or F
● Meta analysis review identifies all the
relevant studies on a given topic

Answer 32

FALSE
● Systematic review identifies all the
relevant studies on a given topic

Question 33

This study assesses, synthesizes,
interprets the findings and finally
presents an impartial, unbiased, and
balanced summary of the evidence.

Answer 33

Systematic Review

Question 34

T or F
Meta analysis is a study that uses
data from all the studies that
consider the same question and use
the same study design.
● It uses data from these studies to
combine statistical analysis and
produces a single summary result.

Answer 34

TRUE

Question 35

Factors that are positively associated with the
risk of development of a disease but that are not
sufficient to cause the disease

Answer 35

rISK fACTORS

Question 36

Levels of prevention

Answer 36

Primordial Prevention
primary Prevention
○ Secondary Prevention

○ Tertiary Prevention

Question 37

consists of measures to reduce impairments and
disabilities, minimize suffering caused by poor
health and promote patient’ adjustment to
incurable conditions

Answer 37

○ Tertiary Prevention

Question 38

to reduce the more serious consequences of
disease through early diagnosis and treatment;
directed at the period between disease onset and
normal time of diagnosis
★ It can only be applied to diseases in which the
natural history includes an early period, when it
is easily identified and treated, so that the
progression can be stopped

Answer 38

Secondary Prevention

Question 39

to avoid the emergence and establishment of the
social, economic, and cultural patterns of living
known to contribute to an elevated risk of
disease.

Answer 39

Primordial Prevention

Question 40

to limit the incidence of disease by controlling
specific causes and risk factors
■ Population approach
■ High-risk approach

Answer 40

Primary Prevention

Question 41

The process of usings tests on a large scale to identify
the pressure of disease in apparently healthy people.
○ Screening tests do not usually establish a diagnosis,
but rather the presence or absences of an identified
risk factor, and thus require individual follow-up and
treatment.

Answer 41

Prevention: Screening

Question 42

Types of screening:
○ Mass:

○ Multiple or multi-phasic:

○ Targeted:

○ Case-finding or opportunistic:

Answer 42

○ Mass
★ This aims to screen the whole population, or a subset of the population.
○ Multiple or multi-phasic
★ It’s just a use of several screening tests.
○ Targeted
★ This is the screening of groups with specific exposures like the workers in the lead battery factories.
○ Case-finding or opportunistic
★ consult a health practitioner for other purposes.

Question 43

Prevention: Screening criteria

Answer 43

○ Disorder
○ Prevalence
○ Natural history
○ Test choice
○ Test performance
○ financial/costs
○ Acceptability
○ Equity
○ Reliability

Question 44

t’s getting the same results for a repeated administration of your desk, meaning it’s reliable

Answer 44

Reliability