1.4 Observational & Experimental Studies

Medical records of a group of residents of a town are compared to the medical records of a group of residents of another town. Researchers are curious to see if one town appears to be “healthier” in general.

• Observational Study

• Experiment

• Simulation

• Survey

A group of 400 adults suffering from back pain is divided into two groups. One group of 200 people is given a medication in pill form, while the other group of 200 people is given the medication in the form of a shot.  Results for each group are compared to see if there is a difference in pain relief between the two methods.

• Observational Study

• Experiment

• Simulation

• Survey

A Principal took a random sample of students and asked them about their favorite subject in school. The data showed that a large percentage of students prefer math over any other subject.

• Observational Study

• Experiment

• Simulation

• Survey

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.

• Observational Study

• Experiment

• Simulation

• Survey

A school studied 100 students as they went through elementary school. The school recorded how often their parents read to them over the years and then measured how well the students did in school.

• Observational Study

• Experiment

• Simulation

• Survey

A surgical simulator is used to test new equipment safely without the risk of harming real patients. The results of the simulator are recorded for further study to determine the effectiveness of new equipment.

• Observational Study

• Experiment

• Simulation

• Survey

A group of 600 registered voters in a given county are asked how they intend to vote in an upcoming election. A summary of their responses is posted on a news web-site, and it is implied that this group is representative of all registered voters in that county. The responses are used to predict the outcome of the election.

• Observational Study

• Experiment

• Simulation

• Survey

A pharmaceutical company wanted to check whether their new cough medicine really relieve​s coughs.

To do that, they went over medical records of all clinics in the country and looked for an association between the type of medicine prescribed for patients who suffer from coughs and the level of their recovery.

• Observational Study

• Experiment

• Simulation

• Survey

A teacher wanted to analyze whether rewarding students for correct answers with candy would lead to those students scoring well on quizzes in class. She decided to give out candy to students in her first block class when they answered correctly, but not reward the students in her second block class for correct answers. She continued this for 6 weeks and recorded students’ quiz grades throughout that time. She then compared the two groups to determine whether there was a correlation or not.

• Observational Study

• Experiment

• Simulation

• Survey

Harley-Davidson Motorcycles uses a driving simulator to study the safety of its latest model of motorcycle. The results are recorded to determine if the model is ready for final production or needs further refinement.

• Observational Study

• Experiment

• Simulation

• Survey