Keywords: rwd
Advances in quality and timeliness of data derived from electronic health records has created the interest to use real world data as a comparator arm to assess activity of experimental therapies tested in single arm clinical trial trials. An assessment of the extent of potential confounding is needed to use an external control arm in lieu of a randomized control arm. We built external control arms to compare to the experimental arms of past RCTs in advanced non-small cell lung cancer. Results were compared against original RCTs comparisons to assess performance.