Currently, I am trying to extract the HR and 95% CI from a kaplan meier curve (used DigitizeIt plus the spreadsheet provided by Tierney et al)
[Tierney JF, Stewart LA, Ghersi D, Burdett S, Sydes MR. Practical methods for incorporating summary time-to-event data into meta-analysis. Trials. 2007 Dec;8(1):16.]
I'm comparing the yellow and blue curves. In the main paper the authors state that the logrank test has found the difference in curves to be significant p=0.03.
I then proceeded to trace the KM curve and input the datapoints into the spreadsheet provided by Tierney et al. The resultant HR between the curves was 1.47(0.85-2.53), the p value will not be significant in this instance.
So then my question is: Is it plausible for the p-values to be divergent in both the logrank and the cox regression? If so, what does that mean?