Study designs

Question 1

2 components of study design

Answer 1

Population:from which groups of subjects are studied
Outcomes:that are measured

Question 2

components of analytic studies

Answer 2

1.intervention
2.exposure

Question 3

spotting the design:
what is the 2 aims of the study?

Answer 3

1.describe population(descriptive)
2.qauntify the relationship between factors (analytical)-PICO questions

Question 4

spotting the design, step 2:

Answer 4

1.yes(RCT)
2.No(observational)

Question 5

spotting the design step 3:

Answer 5

-period after exposure or intervention-cohort study
-same time as exposure or intervention-cross-sectional analytical study
-before the exposure was determined-case control study

Question 6

Descriptive studies

Answer 6

-describe patterns of disease occurrence in relation to variables such as person, place and time
-first step into a new topic-event, disease and or condition

Question 7

what are the 2 aims for descriptive disease

Answer 7

1. emphasis features of a new condition
2. describe the health status of communities or populations

Question 8

descriptive question include 5 W

Answer 8

what, where, why, who when

Question 9

descriptive study(what)

Answer 9

condition or disease being studied?
-magnitude of problem, prevalence of disease or health-related event

Question 10

descriptive study-why, can a descriptive study confirm causative/ risk factors?

Answer 10

no

Question 11

3 examples of individual studies

Answer 11

1.case report
2.case series
3.cross sectional study

Question 12

example of population level

Answer 12

correlational/ecological study

Question 13

correlation/ecological studies advantage

Answer 13

use available data-quick and inexpensive

Question 14

2 Limitations of correlation/ecological studies

Answer 14

1.the degree of association does not reflect an individual-level relationship
2.changes associated with exposure can be masked

Question 15

3 features of an analytical studies

Answer 15

1.carried out to find the answer to why
2.test hypothesis
3.has a comparison group
-study group
-control group

Question 16

first step of case control design

Answer 16

1.start with disease(cases)
control group:those without disease
-both groups should be at same risk of being exposed to the factor of interest

Question 17

3 case control studies advantages

Answer 17

quick and inexpensive
useful to investigate rare disease
minimal ethical issues

Question 18

3 disadvantages of case control studies

Answer 18

1.recall bias :has to depend on memory or past records to determine exposure
2.difficult to select an appropriate control group
3.cannot measure the incidence

Question 19

what happens in a cohort study?

Answer 19

investigator selects a group of exposed individuals and group of non-exposed and follows up both groups to compare the incidence of disease

Question 20

2 types of cohort studies

Answer 20

1.prospective cohort
2.retrospective (historical)

Question 21

2 types of experimental studies

Answer 21

1.clinical trials-on patients with disease e.g immunisation trial
2.prevention trials-on healthy people/ people at risk of certain conditions e.g community trial