Exam 8: Muddied Waters: The Challenge of Confounding

In a study of illicit drug use and attempted suicide the crude relative risk is 2.1 overall but it is 3.4 for men and 1.3 for women when the sexes are considered separately. This suggests that:

In a study of alcohol and oral cancer the crude relative risk is 4.0 overall but it is 2.0 for men and 2.0 for women when the sexes are considered separately.This suggests That:

Using the directed acyclic graph below to identify which of the following statements are true? (Select all that apply)

An intermediary variable is not a confounder because:

Which of the following statements best describes the potential effects of confounding?

When does confounding occur?

Which two of the following methods cannot be used to prevent confounding from occurring in a study?

What is the best single way to prevent confounding from affecting the results of a study?

The table below comes from a study of ovarian cancer survival in Australia (Anuradha et al., 2015). Risk of mortality in a prognostic cohort study of women with invasive epithelial ovarian Cancer according to the number of comorbidities at time of diagnosis (Australia, 2005) These data suggest that (select all that apply):

Why might adjustment for age affect the magnitude of the association between comorbidities and ovarian cancer?