Randomization and masking
Subjects were stratified by clinical center, and after obtaining informed consent and verifying eligibility criteria were met, subjects were randomized. Treatment assignments were stratified by clinical center and generated using a pseudo-random number generator with randomly permutated blocks. These assignments were stored in the Medidata Rave cloud-based data management system developed by the contracted research organization. All subjects underwent the harvesting procedure per their assigned study arm, then per the randomization scheme they were blinded to the actual treatment received (for example, SVF versus CSI, BMAC versus CSI, or cells versus CSI). As a single-blinded study, the site principal investigators were not required to be blinded. However, subjects were blinded to their injection. The blinding was implemented by limiting visualization of the syringe contents with opaque covering in addition to performing sham BMAC and SVF harvests in patients within certain cohorts.