Research participants are involved in a trial that incidentally separates them into two groups. One group receives an intervention, while the other group does not. Both groups are compared for outcomes. What type of research method is this?
Correct Answer: C
Rationale: A randomized controlled trial is a research method in which participants are randomly assigned to either a treatment or control group. This design helps eliminate bias and allows for the comparison of outcomes between the two groups. In this scenario, where participants are separated into intervention and non-intervention groups for comparison, it aligns with the characteristics of a randomized controlled trial. The key feature distinguishing it from the other options is the random assignment of participants to groups, ensuring that both groups are comparable at the start of the study. Double-blind experiments involve blinding both participants and researchers to treatment allocation, which is not explicitly mentioned in the scenario. Experimental design refers to a broader category that includes various types of research designs beyond just randomized controlled trials. Repeated measures design involves collecting multiple observations from the same participants over time, which is not the case described in the scenario.