We then evaluated the percentage of the TE effect accounted for by PTSD. This percentage was calculated as follows: ([exp(τ)-exp(τ′)]/[exp(τ)-1)])×100, where exp(τ) was the odds ratio (OR) for the TE effect without PTSD symptoms in the model and exp(τ′) was the OR for the TE effect with PTSD symptoms in the model (28). When the ORs for the TE effect are the same whether or not PTSD symptoms were included in the regression model [i.e., exp(τ) = exp(τ′)], this equation evaluates to 0%. When there is no remaining TE effect when PTSD symptoms are included in the model [i.e., exp(τ′) = 1)], this equation evaluates to 100% (28). Empirical CIs and p values were calculated for this percentage.
