Instruction 15-6
Four Surgical Procedures Currently Are Used to Install

question 70

Short Answer

Instruction 15-6
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 centre wants to compare the proportion of clear operations for the four procedures, and collects the following numbers of patients from their own records:
| Procedure |
$$\begin{array} { | l | c | c | c | c | c | } \hline & \text { A } & \text { B } & \text { C } & \text { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\hline \text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142 \\\hline\end{array}$$ They will use this information to test for a difference among the proportion of clear operations using a chi-square test with a 0.05 level of significance.
-Referring to Instruction 15-6,the test will involve _______ degree(s)of freedom.

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Definitions:

Release of Cortisol

The Release of Cortisol refers to the secretion of the hormone cortisol by the adrenal glands, often in response to stress, which plays a crucial role in many body functions.

Blood Flow

The movement of blood through the circulatory system, delivering nutrients and oxygen to cells and removing waste products.

Brain Areas

Brain Areas are specific regions within the brain that are responsible for different functions related to cognition, perception, emotion, and bodily operations.

German Students

Refers generally to students who are either from Germany or studying within the German education system.