BMTRY 747 – Foundations of Epidemiology II
Class discussion
January 8, 2015
Nancy Krieger: “Epidemiology and the web of causation: Has anyone seen the spider?”
How important do you think it is for epidemiologists to look for social determinants of health?
The web of causation model proposed by McMahon (Figure 1) shows dots going off the page. What do those dots lead to? Are they appropriate objects of epidemiologic research?
What are the advantages and disadvantages of “cutting causal strands” close to the outcome of interest? (i.e. proximal causes)
Is it possible or desirable to intervene at more distant or upstream level? What are the consequences of doing so, if it is possible?
Do you agree that the methodologic framework employed by epidemiologists can drive or influence the 1) etiologic explanations resulting from the research and 2) the research agenda? How might this happen? Can you think of any examples?
During the 1950s in the US, Krieger argues that research into social determinants of health was suppressed by the anti-communist political environment, and the resulting taboo against discussing social class and social inequality. Is this taboo still relevant?
Lew Kuller has asserted (6 lines from the bottom left of p. 893) that claims about multifactorial etiology may sometimes be more a matter of ignorance than insight. The advances in genetic epidemiology and other types of molecular epidemiology are similar in a way to early germ theory, and could emphasize the importance of single causes for single diseases. How do we balance an increasing understanding of specific strands to cut in the causal pathway to prevent disease, versus a more global view of public health and more upstream determinants of disease?
Krieger argued that epidemiologists had not yet developed a theoretical framework integrating social and biological understandings of health and disease (top p. 896). What are the important components of her proposed ecosocial framework? What are the advantages of this framework?