IPPCR 2019 Issues in Randomization Part 1 of 4

>> Paul Wakim: Hello, I'm Paul Wakim. I am chief of the Biostatistics and Clinical Epidemiology Service at the NIH Clinical Center and this is a four-part talk on randomization in clinical trials. In the first part, we're going to talk about the what, why, and who; and in parts two and three, we're going to talk about how to randomize; and in part four,

we'll discuss miscellaneous points and recommendations. So, let's start with the what, why, and who. So, when you do a study, you start -- you know, there's all these individuals that are out there with the disease or the condition or disorder that you are trying to study. And then of those, some are interested in

participating in the clinical trial. And of those, some will be eligible and will meet the inclusion/exclusion criteria. Of those, some will consent; and of those, they will be randomized. Those are going to be randomized. And so, we're going to talk in part four about the representation of those who are randomized that are presentativeness [phonetic sp] of

those who are randomized, but for now, we are at the stage of randomization. So, the point of the slide is to show that there is a lot going on before randomization, but this talk is about at the stage of randomization. So, what is random? Random is basically having no specific pattern. So, you -- and unpredictable, so you

cannot tell what's the next assignment going to be or what the next item is going to be, that's random. What is randomization? In the clinical trial context, randomization is a method based on known chance alone by which eligible and consented participants are assigned to one of the study interventions. So, you have several interventions, and you