The 'Table 2 fallacy'
21st December 2022 I was asked a question the other day that got me reflecting on some issues in causal inference. The question was this: ‘…if a multivariable model includes all the relevant potential confounders then what is the advantage of using causal modelling methods ?’ Having reflected a bit on my own training in causal inference and after a quick Google I found this paper: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3626058/ The ‘Table 2 Fallacy’ refers to the assumption that all the effects of covariates estimated in a multivariable model are independent effect sizes. Indeed, the main exposure of interest is treated like any other covariate within a multivariable model. It’s called the ‘Table 2 Fallacy’ because observational studies often use Table 1 to present the descriptives of the data used and Table 2 the results of a multivariable analysis. In my case it should probably be called the ‘Table 3 Fallacy’ as I usually use Table 2 to present my univariable results...