There are four main questions that you need to ask when trying to determine which is the appropriate statistical test of means for your research problem. These questions focus on the scale of measurement, research design, known information, and the assumptions of the statistical test. Each question is presented below.

1. What is the scale of measurement of the dependent variable?
   
   
2. How many samples of data are collected in the research design?
   Are the samples dependent?
   Are the samples independent?
   
   
3. What information is known?
   
   
4. Have you met the assumptions of the statistical test selected?