Question

Which option identifies the sampling technique represented in the following scenario? An ophthalmologist wishes to measure the rate of occurrence of glaucoma in patients that come to her eye clinic. Each patient is assigned a number from 1 to 1,040. A random number generator is used to select a starting number. The selected number is 8. Every tenth patient is then evaluated for glaucoma. In other words, patients 8, 18, 28, 38, 48, 58, 68, etc. were selected to complete the survey.

A. cluster sampling
B. stratified random sampling
C. systematic random sampling
D. mixed/multi-stage random sampling

Answer 1

The answer is C. Systemic random sampling.

By definition, systemic random sampling is a sampling technique where the respondents are selected according to a random starting point (this alone shows that the answer is C.) The researcher then chooses the sample interval, which is the difference between two consecutive  numbers in the progression. 

In this case, the starting point is 8 and the sample interval is 10.

The answer is C.