“…While it is a limitation of our analyses that we did not include recruitment time, analysis time, or space rental in our calculations, it would be simple enough for other researchers to add these costs to the equation if they were available for a particular study. We believe that inclusion of these variables would likely further increase FG costs relative to IDI costs, given the additional time and costs associated with FGs in all of these areas (see Coenen, Stamm, Stucki, & Cieza, 2012, for detailed comparisons of time required for FG and IDI activities, including recruitment and analysis). Given these differences, we estimate that our comparative cost-effectiveness calculations are on the conservative side and would expect IDIs, in many contexts, to be even more cost-effective, relative to FGs, than our data indicate.…”