Four Surgical Procedures Currently Are Used to Install Pacemakers $\quad$

question 203

Short Answer

Four surgical procedures currently are used to install pacemakers. If the patient does not need to return for follow-up surgery, the operation is called a "clear" operation. A heart center wants to
Compare the 4 procedures, and collects the following numbers of patients from their own records: $\quad$ $\quad$ $\quad$ $\quad$ $\quad$ $\quad$$\text { Procedure }$
$\begin{array}{l|cccc||c} & \text { A } & \text { B } & \text { C } & \text { D } & \text { Total } \\\hline \hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \hline \text { Total } & 38 & 56 & 30 & 18 & 142\end{array}$

Which of the following tests will be the most appropriate to find out whether the 4 procedures are equally effective?
a) $\chi ^ { 2 }$ test for difference in proportions.
b) $Z$ test for difference in proportions.
c) One-way ANOVA $F$ test for differences among more than two means
d) Kruskal-Wallis rank Test.

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Definitions:

Transcranial Direct Current Stimulation (tDCS)

Transcranial Direct Current Stimulation (tDCS) is a form of neurostimulation that uses constant, low current delivered directly to the brain area via electrodes on the scalp to modulate neural activity.

Psychological Disorders

Mental disorders characterized by dysfunctions in cognition, emotions, or behavior that lead to significant distress or impairment in daily functioning.

Brain Stimulation

A treatment method involving the use of electrical impulses to stimulate or modulate brain activity, often used for neurological or psychiatric conditions.

Bilateral Anterior Cingulotomy

A neurosurgical procedure targeting the anterior cingulate cortex of the brain to treat certain psychiatric disorders.