Achievements and Challenges of Evidence-Based Medicine in Hematopoietic Stem Cell Transplantation: An Analysis of Single-Center and Multicenter Trials

Abstract

Randomized multicenter trials in the area of hematopoietic stem cell transplantation (HSCT) face considerable challenges, therefore, their amount is relatively small. Most clinical guidelines are based on the data of multicenter registry studies or well-controlled prospective single-center non-randomized studies. To determine the criteria of a well-controlled single-center trial the results of which can be confi rmed by a multicenter analysis, the total of 44 groups of patients from 22 cooperative studies in collaboration with EBMT were analyzed. The results of these studies were compared with single-center data and the results of the planned studies of RM Gorbacheva Scientifi c Research Institute of Pediatric Oncology, Hematology and Transplantation. In 43 % of cases signifi cant diff erences were observed. The probability of diff erences did not decrease with an increasing number of patients in the single-center groups, but became higher (odds ratio 1.037; 95% confi dence interval 1.001-1.074; p = 0.046), which highlights the diff erences in methods of single- and multicenter trials. While analyzing the reasons for signifi cant diff erences the following necessary criteria for high-quali ty single-center trials in the area of HSCT were formulated: 1) conditioning regimens and graft-versus-host disease prophylaxis (if they are not subject of the study) need to be consistent with the most frequently used practices; 2) groups of patients should be status-homogeneous; 3) the trial must not include patients treated more than 5 years before the analysis; 4) patients should receive current antitumor therapy at pre- and post-transplantation stages; 5) each compared group should include more than 30-40 patients