A comparison of randomized concurrent control groups with matched historical control groups: are historical controls valid?

The use of a historical control group is predicated on the assumption that survival and relapse-free survival in the historical control group closely approximate the survival and relapse-free survival in a randomized concurrent control group. This assumption has never been tested. This study compares survival and relapse-free survival in randomized control groups with historical control groups matched for disease, stage, and follow-up. Of the 43 matched control groups, 42% varied by more than 10 percentage points, 21% varied by more than 20 percentage points, and 5% varied by more than 30 percentage points. Of the 18 that varied by greater than 10 percentage points, 17 had superior survival or relapse-free survival in the randomized concurrent control group. This study indicates that the assumption that historical control groups may replace randomized concurrent control groups is not valid.

Duke Scholars

Author Louis Frederic Diehl Medicine, Hematologic Malignancies and Cellular Therapy