Question

identify whether each scenario is describing an observational study or an experiment. participants are assigned to either a real yoga class, a fake - yoga class (with stretches made up by a comedian), or no yoga at all. after several sessions, the three groups are interviewed about changes in their sense of well - being. patients are given either a daily dose of aspirin or a sugar pill to investigate if aspirin has an effect on blood pressure students from a local elementary school are tracked for 30 years to look for a link between early - childhood academic performance and quality of life as an adult. medical records from across the country are examined to look for a relationship between population density and mental health

Explanation:

1. In the first scenario, participants are assigned to different treatments (real yoga, fake - yoga, no yoga), which is a key characteristic of an experiment.
2. In the second scenario, patients are given different substances (aspirin or sugar pill) to test an effect, which is an experiment.
3. In the third scenario, students are simply tracked over time without any intervention, which is an observational study.
4. In the fourth scenario, medical records are examined without any manipulation of variables, which is an observational study.

Answer:

1. Experiment
2. Experiment
3. Observational study
4. Observational study