Third, ACE population-attributable fractions (PAF) (Stata version 17 punaf; StataCorp)22 by US state were estimated when AORs indicated statistically significant higher odds (P < .05) of the analyzed conditions among adults with ACEs. Population-attributable fraction is the fraction of all cases of an adverse condition in a population attributable to a specific exposure; despite the causality implied by the term attributable, PAFs based on observational data—as in the present study—are not definitively causal.23 Reference sources for the disease burden estimates to which the ACE PAFs were applied were already adjusted for other health issues (eg, the source for medical spending estimates—as described in the next paragraph—for depression excluded costs for coexisting chronic diseases)24 and, therefore, consistent with previous similar studies, no other adjustment was applied.8,9 However, ACE PAFs adjusted for all analyzed health outcomes are also reported for reference. Adverse childhood experience PAFs for anxiety, interpersonal violence, and illicit drug use (which have documented associations with ACEs but are not measured in the BRFSS) from population-based analysis similar to the US BFRSS in England were added uniformly to all states.8
