Blood Pressure Before and After Medication
Dependent, paired, or two-sample, t-test
Computing a dependent t-score
Controlling high blood pressure is not always determined by eating right and exercising. Sometimes better living through chemistry, in the form of medication, can improve blood pressure. Let's take a look at how we would use a dependent t-test to decide if there is a statistically significant effect of a new blood pressure medication (pre and post testing) to reduce blood pressure in a population.
Using the data set to the right we can follow the eight steps to compute the t-test statistic:
- State the null & research hypothesis
- Select the level of risk
- Select the appropriate test statistic
- Compute test statistic (obtained value)
- Determine the value needed to reject the null
- Compare obtained value & critical value
- Compare the result to the level of significance
- Reject or accept the null based on the comparison
1. The null hypothesis is Ho: µpost-test = µpre--test and the research hypothesis H1: Xpost-test < Xpre--test
2. The level of risk will be .05
3. The appropriate test statistic is:
4. Compute the test statistic value (obtained value) SPSS was used for calculations
