Question

question 15 (4 points)
a doctor wants to survey his patients to find out if they are satisfied with the treatment they received. he plans to obtain a sample of the patients using one of five methods. which method should he choose in order to lead to a sample that is the most representative of the population?

• assign each patient a number and go down the list and select every 20th patient.
• interview patients who have volunteered.
• assign each patient a number and use a random number generator to select the patients.
• assign each patient to a group based on the type of treatment they received and randomly select a percentage of patients from each of the groups.
• ask the next five patients who appear in his office.

Explanation:

To determine the most representative sampling method, we analyze each option:

• Option 1 (Systematic Sampling): Selecting every 20th patient may introduce bias if the list has a pattern (e.g., appointment times, treatment types).
• Option 2 (Voluntary Sampling): Volunteers are self - selected and may not represent the entire patient population (e.g., only highly satisfied or dissatisfied patients volunteer).
• Option 3 (Simple Random Sampling): Assigning numbers and using a random number generator gives each patient an equal chance of being selected. This method minimizes bias as there is no systematic error in selection, and every patient has the same probability of being in the sample.
• Option 4 (Stratified Sampling): While stratified sampling is good for heterogeneous populations, in this case, the goal is to sample all patients (the population is all patients, not groups with different treatments in a way that stratification is necessary here). Also, the problem is about surveying all patients' satisfaction, and simple random sampling is more straightforward for a general population of patients.
• Option 5 (Convenience Sampling): Asking the next five patients is a convenience sample, which is highly biased as it only includes patients who happen to be in the office at that time, not representing all patients (e.g., patients with different appointment times, treatment durations, etc.).

Simple random sampling (Option 3) is the most representative as it gives each patient an equal chance and avoids the biases of the other methods.

Answer:

Assign each patient a number and use a random number generator to select the patients.