Using the directed acyclic graph below to identify which of the following statements are true? (Select all that apply)
A)C is a potential confounder of the relationship between B and D
B)B is a potential confounder of the relationship between C and D
C)C is a potential confounder of the relationship between A and D
D)C is an intermediary between A and D
E)Even if C was not a cause of B, it could still confound the relationship between B and D

Question

Using the directed acyclic graph below to identify which of the following statements are true? (Select all that apply) 
A)C is a potential confounder of the relationship between B and D 
B)B is a potential confounder of the relationship between C and D 
C)C is a potential confounder of the relationship between A and D 
D)C is an intermediary between A and D 
E)Even if C was not a cause of B, it could still confound the relationship between B and D

Quizplus · Accepted Answer

C is a potential confounder of the relationship between B and D
because C is a cause of both B and D (Answer A).B is not a confounder of the
relationship between C and D (Answer B) because it is on the causal pathway from C to
D.Similarly, C is not a confounder of the relationship between A and D (Answer C)
because it is on the causal pathway i.e.an intermediary (Answer D).Because A is a
cause of both B and C, it does not matter whether C is a cause of B, it can still confound
the relationship between B and D (Answer E).As an example of the last situation,
smoking can confound the relation between alcohol and lung cancer even though
smoking does not cause someone to drink alcohol, because there are upstream factors
such as socioeconomic status that influence both smoking and alcohol consumption.

Using the Directed Acyclic Graph Below to Identify Which of the Following