Question

Determine whether the study is an observational study or an experiment. Explain.
A study used periodic blood pressure readings and brain MRIs of adults to find that adults with long periods of high blood pressure were more likely to develop cerebral small blood vessel disease. (Source: American Heart Association)

Accepted Answer

Identify the key characteristics of an observational study: In an observational study, researchers observe and measure variables without manipulating or controlling them. Participants are not assigned to specific groups or treatments by the researchers. Identify the key characteristics of an experiment: In an experiment, researchers actively manipulate one or more variables (independent variables) to observe the effect on other variables (dependent variables). Participants are often randomly assigned to groups or treatments. Analyze the details of the study: The study involves periodic blood pressure readings and brain MRIs of adults. The researchers did not assign participants to have high blood pressure or manipulate their blood pressure levels; they simply observed the participants' natural conditions over time. Determine whether there is any intervention: Since the researchers did not intervene or assign treatments (e.g., controlling blood pressure levels), this indicates that the study is observational rather than experimental. Conclude: Based on the lack of manipulation or intervention, the study is an observational study. The researchers observed the relationship between high blood pressure and cerebral small blood vessel disease without influencing the participants' conditions.

비슷한 문제에 대한 검증된 영상 답변:

주요 개념

Observational Study

Experiment

Causal Inference