STUDY DESIGN I (DESCRIPTIVE) Flashcards
Which is cheaper
Which is less feasible
Which is less popular
Which is quicker to finish
Which has more ethical issues
Observational or Experimental
Observational
Experimental
Experimental
Observational
Experimental
Observational studies allow nature to take its course.
T/F
T
In Observational studies, The investigator measures and intervenes
T/F
F
The investigator measures but does not intervene
Types of Observational studies:
________
____________
Descriptive
Analytic
____________ is often the first step in an epidemiological investigation.
Descriptive study
Descriptive studies describe patterns of disease occurrence in relation to variables such as ____,_______, and ________
person, place, and time.
The data provided by descriptive studies are essential for public health ____________ as well as ___________.
administrators
epidemiologists
For public health administrators:
knowledge of which populations or subgroups are ________________________ allows the most efficient allocation of resources and the targeting of particular segments of the population for _______________________
most or least affected by disease
education and/or prevention programs
For epidemiologists:
the identification of _________ frequently constitutes an important _____ step in the search for determinants of risk factors that can be altered or eliminated to reduce or prevent disease
descriptive characteristics
first
Descriptive studies use information from such diverse sources as
________,
___________ records,
employment ____________,
clinical records from hospitals or private practices, as well as national figures on consumption of foods, medications, or other products (NDHS).
census data
vital statistics
health examinations
descriptive studies
They are used to describe __________ and ___________
They are also used to formulate ___________
patterns and frequency of disease occurrence
research questions.
There are three main types of descriptive studies:
_________ studies: which consider pattern of disease among __________
________ or __________ (_________)
_____________ surveys of individuals
Correlational studies; populations
Case reports or case series ; individuals
Cross-sectional
Correlational studies
A correlational study determines whether or not ————————
two variables are correlated.
Correlational studies
It is very important to note that correlation doesn’t imply _____ and there is no way to _________________[
_____from a correlational study.
This is a common mistake made by people in almost all spheres of life.
causation
determine or prove causation
Correlational studies
There are three types of correlates that are identified;
_______ correlation
_______ correlation
_______ correlation
Positive correlation
Negative correlation
No correlation
Correlational studies
Positive correlation – when an increase in one variable leads to _______ in the other and a decrease in one lead to ___________ in the other.
an increase
A decrease
Correlational studies
Negative correlation – when an increase in one variable leads to _________ in another and vice versa.
a decrease
Correlational studies
No correlation – two variables are uncorrelated. When a change in one ________________in the other and vice versa.
does not lead to a change
Strength of correlational studies
It is done ______
It is _________
Uses ____________ data
quickly
inexpensive
already available
Limitation of correlational studies
Inability to link ______________ in particular individual
Inability to control for the effects of _________________
It represent ___________ levels rather than _________ values
exposure with disease
potential confounding factors.
average exposure; actual individual
Case reports and case series
Case reports and case series describe the experience of ________ or __________ with (a similar or different?) diagnosis.
a single patient
a group of patients
A similar
Case reports and case series
This type of studies, in which a clinician identifies an unusual feature of a disease or a patient’s history, may lead to _____________________.
In this way, case reports and case series represent an important interface between _____________ and _________
formulation of a new hypothesis.
clinical medicine and epidemiology.
Case report and series
The collection of a case series rather than reliance on a single case report can mean the difference between _________________ and merely _______________
formulating a useful hypothesis
documenting an interesting medical oddity.
Case reports and case series
Strength of case report and case series
Help in the ______ of new disease
______________ concerning possible risk factors.
recognition
Formulation of hypothesis
Limitation of case report and case series
They cannot be used to test for _____________
Case report is based on the experience of _______________
presence of valid statistical association
only one person
Cross-sectional Studies
This is the study in which ___________ status is assessed __________ among individuals in a well-defined population.
exposure and disease
simultaneously
Cross-sectional Studies
Measure the ___________ of disease and thus are often called ________ studies.
prevalence; prevalence
Cross-sectional studies
The status of an individual with respect to the presence or absence of _____________________ is assessed at the same point in time.
both exposure and disease
In cross-sectional studies
It is difficult to distinguish whether __________________________ or whether ___________________
the exposure preceded the development of the disease
presence of the disease affected the individual’s level of exposure.
Cross-sectional studies are relatively easy and inexpensive to conduct.
T/F
T
In _______________ of disease, a cross-sectional study to measure several exposures can be the most convenient first step in investigating the cause.
sudden outbreaks
Data from cross-sectional studies are helpful in assessing the health care needs of populations.
T/F
T
Cross-sectional Studies
In one special circumstance, a cross-sectional study can be considered as a type of analytic study and used to test epidemiological hypotheses.
This can occur only when the current values of the exposure variables are _____________ , thus representing the ___________________
unalterable over time
value present at the initiation of the disease.
Cross-sectional Studies
Strength
Cross-sectional studies can also be used to provide information on the ________ of disease or other health outcomes in certain occupation
Since the cross-sectional study must consider ______ rather than ________ cases, the data obtained will always reflect ___________ as well as _______.
prevalence
prevalent; incident
determinants of survival
aetiology
Cross-sectional Studies
Limitation
Since exposure and disease status are assessed at a single point in time, in many cases, it is not possible to determine whether ___________ or ___________.
This type of “chicken or egg” dilemma is common to virtually all cross-sectional data.
the exposure preceded or resulted from the disease
