Number needed to treat
Good Outcome Bad Outcome
control 55 233
experimental 36 252
Calculated results
80.90 percent of control subjects had the adverse outcome.
87.50 percent of experimental subjects had the adverse outcome.
The difference, the absolute risk increase, is 6.60 percent.
The 95% confidence interval for this difference ranges from 0.66% to 12.53% .
The NNH (Number Needed to Harm) is 16 . This means that about one in every 16 patients will be harmed by the treatment.
The 95% confidence interval for the NNT ranges from 8.0 to 150.5