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

question 34

True/False

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,there is sufficient evidence to conclude that the proportions between procedure A and procedure B are different at a 0.05 level of significance.

---

Definitions:

Work in Process

Inventory that includes materials that are in the process of being manufactured but are not yet completed products.

Raw Materials

Basic materials used in the production process, not yet converted into finished goods.

Work in Process Inventory

Inventory that includes all the materials, labor, and overhead costs for products that are in the production process but not yet complete.

Manufacturing

The process of producing goods through the combination of labor, machinery, tools, and chemical or biological processing or formulation.