Glad it helps. Actually, many more layers of separation than you imagine for clinical trials. (And many variations on how randomization is achieved). Most trials have dozens of independent locations that have little to connection with each other. Typically, the pharmaceutical company contracts with a 'clinical research organization' (CRO) to coordinate it all. The CRO usually uses a separate system and/or company to perform randomization. And the whole thing is potentially monitored by yet another separate agency and subject to legal scrutiny and penalties for wrongdoing by the FDA. You can find more deets at clinicaltrials.gov. have fun 👍