Question

I am having trouble figuring out this question with what formula to use and how to input it correctly. I need all work shown, so I understand how to do this. Thank you.

A clinical trial is planned to compare an experimental medication designed to lower blood pressure to a placebo. Before starting the trial, a pilot study is conducted involving seven participants. The objective of the study is to assess how systolic blood pressures change over time if left untreated. Systolic blood pressures are measured at baseline and again 4 weeks later. Is there a statistically significant difference in blood pressures over time? Run the test at 5% level of significance.

Baseline: 120 145 130 160 152 143 126

4 weeks later: 122 142 135 158 155 140 130

Answer 1

Baseline	4 weels later	Difference(d)
120	122	-2
145	142	3
130	135	-5
160	158	2
152	155	-3
143	140	3
126	130	-4
	Total	-6

Claim: There is a statistically significant difference in blood pressures over time.

The null and alternative hypothesis is

Level of significance = 0.05

Sample size = n = 7

Sample mean of difference = = - 0.8571

Sample standard deviation of difference = = 3.4365

Test statistic is

Degrees of freedom = n - 1 = 7 - 1 = 6

Critical value = 2.447   ( Using t table)

Test statistic | t | <  critical value we fail to reject null hypothesis.

Conclusion:

There is no statistically significant difference in blood pressures over time.