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

question 103

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 D are different at a 0.05 level of significance.

---

Definitions:

Email Addresses

Digital identifiers used for sending or receiving electronic mail over the internet, consisting of a user name and domain name.

Probability Samples

Sampling techniques that ensure every member of the population has a known chance of being selected for the sample.

Researcher Judgment

The use of personal expertise and knowledge by a researcher to make decisions within the research process.

Stratified Random Sampling

A sampling method that divides the population into smaller groups, or strata, and random samples are taken from each stratum.