DATA COLLECTION IDENTIFYING VARIABLES LIKELY TO BE IMPORTANT TO INCLUDE IN MY ANALYSIS 5/1/17 Flashcards
1
Q
What does a DAG stand for?
A
directed acyclic graphs
2
Q
What does a DAG allow us to do?
A
- summarise the functional, theoretical and speculative relationships between variables relevant to our question
- identify any co-variates acting a confounders so that these can be adjusted for
- identify any measured/able covariates
- identify competing exposures
3
Q
What are confounders?
A
they cause both the outcome and the exposure
4
Q
Why do we need to adjust for confounders?
A
they create a pseudo-causal path between the outcome and the exposure which will generate statical relationship between the 2 even when none exists
5
Q
What are mediators?
A
they case the outcome and are caused by the exposure
6
Q
What are competing exposures?
A
- they cause the outcome
- but no relationship with the exposure
- might have to adjust
7
Q
What can a causal relationship be? (4)
A
- functional
e. g. no contraception –> teenage mother - empirical
e. g. based on previous statical analysis - theoretical
e. g. teenage grandmother -> teenage mother - speculative
e. g. teenage grandfather -> teenage mother
8
Q
When is a causal relationship only possible? (2)
A
- if the cause variable precedes the effect
- assumed to be present between variables that are temporally distributed
