NBME 22 Answers ↦
How are we supposed to know in the question the patients and providers are aware that they know what they are being given?
I went back and forth about it, but in the end figured that they were aware since one regimen involved subQ injection + oral med and the other was subQ injection alone with no oral placebo.
This is a cohort study! (Since it involves splitting people into "groups"; group = cohort.) But the stem asks what "best describes" the design. So, yes, it's a cohort study but a more precise ("more specific") description is Open-label. In other words, "Open-label clinical trial" is a type of cohort study, and, in this case, "Open-label" is a more precise description of what is described in the stem.
It is a cohort, just as @drdoom said, but it isn't an "Observational" one.
It's actually not a cohort study, imo. In a cohort you find people with an exposure and see if they develop some outcome. In this experiment, people were RANDOMLY ASSIGNED to the different exposures. That doesn't happen in cohorts.
It may be a cohort in that these people are in groups, but for the purposes of Step 1, I don't think we will deal with typical "Cohort" studies in which participants are randomly assigned.
you don't administer an intervention in a cohort study, you just observe what happens. it is an observational study.
^ i retract my earlier subcomment! thanks @ashli777 and @pg32 — you guys are right that cohorts do not intervene! in two senses: (1) there is no treatment intervention and (2) there is no “assignment” intervention (either randomly or by selection; that is, investigators do not DESIGN or DETERMINE how groups are formed, even if that means random determination by computer).
there is no washout period and the order of drugs given isn't switched