Because 16% of the patients in the trial were lost to follow-up, it is also important to consider the effect that this missing data could have on the study's results. The magnitude of effect that patient loss to follow-up may have had on this study can be determined by including that 16% of patients in the treatment effect analyses using a range of hypothetical outcomes. The worst-case scenario would be if, at the conclusion of this study, the 6 cryotherapy patients lost to follow-up had wart resolution and the 4 duct tape patients lost to follow-up had residual wart. By adding these 10 worst-case outcomes to the 51 known outcomes, we calculated that wart resolution would have occurred in 73% of patients in the duct tape group and 68% of patients in the cryotherapy group (95% CI, −17 to 28). This 95% CI includes zero, indicating that the 5% difference between the 2 treatment groups is not statistically significant. Therefore, if we take into account the effect that the patients lost to follow-up might have on the results of the study, duct tape therapy would be no more effective than cryotherapy. However, this is a maximally conservative estimate.