Instruction 15-8
Four Surgical Procedures Currently Are Used to Install

question 96

True/False

Instruction 15-8
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 |
$$\begin{array} { | l | c | c | c | c | c | } \hline & \mathrm { A } & \mathrm { B } & \mathrm { C } & \mathrm { D } & \text { Total } \\\hline \text { Clear } & 27 & 41 & 21 & 7 & 96 \\\hline \text { Return } & 11 & 15 & 9 & 11 & 46 \\\hline \text { Total } & 38 & 56 & 30 & 18 & 142 \\\hline\end{array}$$ 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 15-8,there is sufficient evidence to conclude that the proportions between procedure B and procedure D are different at a 0.05 level of significance.

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Definitions:

Percent

A measure expressed as a fraction of 100, representing a part of a total.

Avoidant Attachment

A type of attachment style characterized by difficulty in trusting others, emotional distance, and reluctance to depend on others for emotional support.

Anxious Attachment

A type of attachment characterized by insecurity and worry about relationships, often stemming from inconsistent caregiving experiences in childhood.

Secure Attachment

A strong and positive emotional bond between a child and their caregiver, characterized by trust and a sense of safety.