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

question 53

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,what is the value of the critical range for the Marascuilo procedure to test for the difference in proportions between procedure B and procedure D using a 0.05 level of significance?

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Definitions:

Scientific Process

A systematic and empirical approach to research in which the researcher generates a hypothesis, collects data through observation and experimentation, and then analyses the data to draw conclusions.

Developing Theory

Refers to the ongoing process of creating, testing, and refining concepts and propositions that aim to explain phenomena within a certain field.

Observation

The process of monitoring or recording systematically selected behaviors, phenomena, or variables for the purpose of analysis.

Hypothesis

A proposed explanation for a phenomenon, made as a starting point for further investigation.