Question

Please Help: Either C or E

In one study on the effect of tea tree oil on acne, 65 subjects were chosen randomly to use tea tree oil and 65 were chosen to use a placebo. In a second
study, 165 subjects who acknowledged being long-time tea tree oil users had their acne compared with those of 165 people who had never used tea tree
oil. Identify the types of studies performed.

Both studies were controlled experiments.

Both studies were observational studies.

Each study was part controlled experiment and part observational study.

The first study was an observational study whereas the second was a controlled experiment.

The first study was a controlled experiment whereas the second was an observational study.

Answer 1

I think it’s E... because the first one was controlled and the second one is just observing the people that used it and the people that didn’t

Answer 2

In the study of the effect of tea tree oil, the first study was a controlled experiment, whereas the second was an observational study.

What is the type of statistical study?

Statistical study is used to obtain the data and examine this data in the way, that its effectiveness can be measured.

There are three main types of statistical study-

• A. Experiment-In this type of statistical study, the observer or the researcher see the change in the variable of a study with change in other variable experimentally by providing the necessary conditions.
• B. Observational study-In the observational study of statistics, the value of the variables are recorded for different associates of the set.
• C. Survey-In the survey type of study, the data is gathered by directly asking the queries to the people regarding the study.

In one study on the effect of tea tree oil on diseases, 65 subjects were chosen randomly to use tea tree oil and 65 were chosen to use a placebo.

In this study, researcher take the actual data and experiment is conducted.

In a second study, 165 subjects who acknowledged being long-time tea tree oil users had their diseases compared with those of 165 people who had never used tea tree oil.

Here, in this, study, only the observation of those who used the oil matters.

Hence, in the study of the effect of tea tree oil on diseases,  the first study was a controlled experiment, whereas the second was an observational study.

Learn more about the type of statistical study here;

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