Primary Data Studies: Diverse Attributes

1 Comparative vs. non-comparative 2 Separate control group (external factor) vs. no separate control group (internal) 3 Participants defined by a health outcome vs. by having been exposed to, or received or been assigned, an intervention 4 Prospective vs retrospective 5 Interventional vs. observational 6 Experimental vs. non-experimental 7 Random assignment vs. non-random assignment of px to treatment and control groups