Which of the following is an example of an experimental study:

Is your statistical study observational or experimental? Let us find out.

Statistics is the science and the art of learning from data. 🎓 As a discipline, it is not only concerned with the collection, analysis, and interpretation of data but also with the presentation and communication of results based on the analysis performed on the data.

The purpose of a study is often to investigate the relationship between two or more variables involved in the study. For example, does exercise reduce weight? or do people who drink milk before bedtime tend to go to sleep earlier than the people who drink coffee?

The study we conduct to perform statistical analysis of our data can majorly be of two types — Observational and Experimental.

When we read about any research, we usually do not pay attention to how the study was designed. However, to understand the quality of the results/findings claimed by the study, it is extremely important for us to know this.

I myself never paid attention to any research as to how it has been designed and rather believed the claims made by it. I know that was a stupid move but yes I was unaware of the types of studies earlier. I hope you guys are aware of them. If not, then this article can help you understand the concept well. 😎

A simple example of research that many people generally believe to be accurate is regarding food/health/nutrition. They are generally in the news headlines and widely shared on social media too. One day we might read a study claiming that eggs increase the risk of cancer and the following day we might read a claim saying that they are extremely healthy. (Note that, this is just an example to state my point clearly).

We can observe that different studies claim most food items to be either positively or negatively associated with health, which might be true in some sense. For example, the excess intake of a highly nutritious food item can negatively affect the body. But it is extremely important to make sure that the evidence/claim we are reading about is reliable or not.

So, let us find out what these studies tell us using some example problems.

1. Observational Study 👀

In this type of study, we measure or survey members of a sample without trying to affect the members or manipulating the variables. Here, we simply observe what is happening and record the observations. So, it would be correct to say that researchers do not impose any kind of treatment or restriction to the group nor do they randomly assign the subjects to a group. There is basically no manipulation of the environment in which the subject occurs.

Thus, this type of study shows that there may be a relationship between variables but it is not necessary to be a cause and effect (causal) relationship. And, even if the observational study shows a cause-effect relationship, the evidence provided by it is generally considered to be weak.

An opinion survey asking questions about how people liked the most recent documentary is an example of an observational study. Here, the researchers have no control over the participants.

Some of the key points about observational studies are as follows:

• Observational studies are less expensive than experimental studies.
• The time required for the completion of observational studies can be several years to decades.

2. Experimental Study 💊

In this type of study, we randomly assign a treatment to a group so that the researchers can draw the cause and effect (causal) conclusion. This random assignment of treatments is what distinguishes both the studies (observational and experimental). Here, we experiment and manipulate the environment of the subject to measure the response (dependent) variable. Evidence provided by the experimental study is considered to be stronger than the observational study.

This type of study is also sometimes called a scientific study because of the treatment involved in it.

Note: The experimental study involves two groups — experiment group and control group. Control group is the group in the study that does not receive treatment by the researchers.

Some of the key points about experimental studies are as follows:

• Experimental studies are closely monitored.
• Experimental studies are expensive.
• Experimental studies are typically smaller and shorter than observational studies.

Now, let us understand the difference between the two types of studies using different problems.

Problem 1:

A study took a random sample of students and asked them about their bedtime schedules. The data showed that people who sleep for at least 8 hours before the exam day were more likely to get good grades than those who sleep for less than 8 hours.

Type of Study: Observational

Reason: The study is a kind of a survey that just asked people about the number of hours they sleep right before the exam day and how many marks they scored. Since the people were not randomly assigned to any group or given any treatment, the study was an observational study.

Problem 2:

A study randomly assigned people to one of the two groups. Group 1 was asked to follow a strict study schedule for a fixed period of time whereas Group 2 was asked to study in the same way as they used to earlier. The researchers looked at which group scored better in the exams.

Type of Study: Experimental

Reason: The study randomly assigned people to two different groups out of which one group was given a treatment whereas the other group was not. Thus, this was an experimental study.

Problem 3:

A study took a random sample of people and examined their smoking habits. Each person was classified as either a light, moderate or heavy smoker. The researcher looked at the stress level of each group.

Type of Study: Observational

Reason: The study took a random sample of people but does not randomly assign people to different groups. The study simply observed whether the people were light, moderate, or heavy smokers and their stress level. Thus, this was an observational study.

I hope you can now distinguish between experimental and observational studies and can even take responsible decisions for yourself after reading any study.

What is an example of an experiment study?

What is an experimental study?

Which of the following is an example of experimental research quizlet?

What is an experimental study quizlet?