## Comparing Mean Blood Pressure 2

Comparing mean blood pressure
biostatistics

## Question

Vignette: A medical student is conducting a study comparing the mean blood pressure of two groups of patients: one group receiving a new antihypertensive medication, the other receiving a placebo. He collects the following data:

Group 1 (New Medication): Mean blood pressure = 120 mmHg, Standard deviation = 10 mmHg, n = 100 Group 2 (Placebo): Mean blood pressure = 130 mmHg, Standard deviation = 15 mmHg, n = 100

The student wants to determine if there is a significant difference between the two groups. Which of the following statistical tests should the student use to analyze this data?

## Choices

A. Chi-square test

B. Fisher's exact test

C. Independent t-test

D. Paired t-test

E. Mann-Whitney U test

C. Independent t-test

## Explanation

The student should use an independent t-test for this scenario. The independent t-test is used to compare the means of two independent groups of subjects. In this case, group 1 (those receiving the new medication) and group 2 (those receiving the placebo) are independent of each other. The data is also numerical (quantitative), normally distributed, and the sample sizes are equal, which makes the independent t-test the most appropriate choice.

A. The Chi-square test is used for categorical data. B. Fisher's exact test is used when sample sizes are small and the data is categorical. D. The paired t-test is used when the two samples are related or paired, which is not the case in this scenario. E. The Mann-Whitney U test is used when comparing two independent groups, but the data is not normally distributed or the measurement scale is ordinal.

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