Providing Confidence Intervals in Survival Analysis
We highly appreciate Nilforoushan and colleagues’ valuable comments. We agree with their opinion that providing the data on the confidence intervals in the survival analysis is important. Confidence intervals are helpful for the proper interpretation of data and enable comparison of results among different studies. When performing survival analysis, statistical computing packages present standard error (SE) with survival rate. If the acceptable margin of error is considered 1.96 times the SE, a simple way to present the confidence intervals in the survival analysis is “survival rate±1.96 SE.” In our study,1 the SE of the survival rate was 0.07, 0.10, and 0.13, at 1, 2, and 3 years after the operation, respectively. Thus, the 95% confidence interval of the success rate at 1, 2, and 3 years after the operation was 73.3% to 100%, 50.4% to 89.6%, and 26.5% to 77.5%, respectively.