Social epidemiologist Davey Smith (2011) argues that epidemiologists should accept a gloomy prospect: considerable randomness at the individual level means that they should keep their focus on modifiable causes of disease at the population level. The difficulty epidemiology has had in moving from significant population-level risk factors to improved prediction of cases at an individual level is analogous to the lack of success in the search for systematic aspects of the non-shared environmental influences that human quantitative genetics claims overshadow common environmental influences (e.g., the family’s socioeconomic status which siblings have in common). This article responds to the argument and analogy, aiming to draw three audiences—social epidemiologists, human quantitative geneticists, and philosophers of science—into a shared discussion that centers not on randomness, but on heterogeneity in various forms.
Nature-Nurture? No: Moving the Sciences of Variation and Heredity Beyond the Gaps
Almost every day we hear that some trait “has a strong genetic basis” or “of course it is a combination of genes and environment, but the hereditary component is sizeable.” To say No to Nature-Nurture is to reject this relative weighting of heredity and environment. Continue reading
For session 2 of my course on epidemiological thinking and population health I state:
Detailed observation (like a naturalist) or detective work–albeit informed by theoretical ideas–may be needed before we can characterize what the phenomenon is we are studying, what questions we need to ask, and what categories we need for subsequent data collection and analysis. (http://ppol753.wikispaces.umb.edu/Epi_2)
This statement invites clarification of what a naturalist or a detective does–what are their methods? Continue reading