mmb vm Flashcards
(17 cards)
What can investigators do and what can’t they do in an observational study?
Do: Investigator may make inquiry, observe, measure different factors and record what happes to study participants
Can’t: Cannot intervene
What can investigators do i an intervention study?
Intervene in a pre-planned way and then measures or records the outcome
What are the types of observational studies ?
Ecological
Cross-sectional
Case-control
Cohort
What are the types of intervention/ experimental studies?
Non-randomised intervention study
Randomised controlled trial (RCT)
What is a cohort study?
A cohort is a defined group of people who are followed up prospectively
What does an observational study examine?
Examine link between an exposure and disease outcome
What can an exposure be ?
Risk and protective factor
What is an example of an observational study?
Does daily aspirin reduce risk of alzheimer’s?
What are the types of exposures?
Host
Environment
Agent/disease
What is a cross-sectioal study?
An observational design that surveys exposure and disease status at a single point in time (a cross-section of the population) (exposure and disease measured at once
What type of study is a cohort study?
Typically prospective
What is a cross-sectional study?
Measure exposures and disease status at one point in time
What is a cohort study?
Identify groups by exposure and look forward to disease outcome
What is a case-control study?
Identify groups by disease status and look backwards to exposure
How do you designa cohort study?
1.Group of people without the disease
2.Divided into a group who are exposed to the factor and group who are not exposed to the factor
3.Than measure who if each group has developed and who hasn’t developed the disease
What are the features of a cohort study?
1.Prospective or longitudinal study
2.Subjects classified by exposure status and followed up over a period of tme to determine disease outcome
3.Usually need a large population even if the disease is common
4.Typically study cause of disease
5.Usually examine many hypotheses and often examine several different disease ouutcome
What makes cohort studies special?
