Answer:
This study design is known as Observational Study.
Step-by-step explanation:
Statistics is the process of collecting data about a group of objects to draw conclusions about populations of those objects. For example,
Here, it is given a research on 100 smokers and 100 non smokers and then interviewing all 200 participants to compare the depression rates on both groups.
Statistics involves a lot of studies, experiments, and data collection. One such type of study is the observational study. An observational study is a study in which the researcher simply observes the subjects without interfering. That is, the researcher has no control over any treatments the subjects may be given or which groups the subjects may be separated into, etc. They just observe the subjects and record data based on their observations.
