Systolic blood pressure of randomly selected HMO patients was recorded on a particular Wednesday, with the results shown here: $$\begin{array}{l}
\text { Patient Age Group }\
\begin{array} { | c | c | c | c | }
\hline \text { Under 20 } & 20 \text { to } 29 & 30 \text { to } 49 & \text { 50 and Over } \
\hline 105 & 110 & 122 & 139 \
113 & 101 & 114 & 115 \
108 & 112 & 128 & 136 \
114 & 127 & 124 & 124 \
123 & 123 & 125 & 123 \
\hline
\end{array}
\end{array}$$ The appropriate hypothesis test to compare the medians is:
A)Wilcoxon test.
B)Kruskal-Wallis test.
C)Levene's test.
D)Friedman test.

Question

Systolic blood pressure of randomly selected HMO patients was recorded on a particular Wednesday, with the results shown here: $$\begin{array}{l}
\text { Patient Age Group }\
\begin{array} { | c | c | c | c | } 
\hline \text { Under 20 } & 20 \text { to } 29 & 30 \text { to } 49 & \text { 50 and Over } \
\hline 105 & 110 & 122 & 139 \
113 & 101 & 114 & 115 \
108 & 112 & 128 & 136 \
114 & 127 & 124 & 124 \
123 & 123 & 125 & 123 \
\hline
\end{array}
\end{array}$$ The appropriate hypothesis test to compare the medians is:
A)Wilcoxon test.
B)Kruskal-Wallis test.
C)Levene's test.
D)Friedman test.

Quizplus · Accepted Answer

Since we have more than two groups (based on age), the appropriate hypothesis test to compare medians is Kruskal-Wallis test. Wilcoxon test is appropriate when we have only two groups. Levene's test is used to test the equality of variances in different groups. Friedman test is used when we have repeated measures data.

Systolic Blood Pressure of Randomly Selected HMO Patients Was Recorded