Question special
Chief Resident

When designing and powering the study, how was the ODI MCID of 10 selected? Although there is a lot of variability in the literature, we often see larger differences cited, such as 15 for FDA submissions, or 30 for the Minnesota Community Measures definition of a "successful surgery." Selecting a smaller threshold both increases the possibility of a false positive, and mandates a larger sample size for otherwise comparable power calculations. Are the results observed in the study preserved in post hoc analysis with a larger MCID?