The significance tests used for means is determined by whether or not the data is weighted and by the Means setting and the Design effect for weight setting in Statistical Assumptions.
If Means = Nonparametric:

 Data is not weighted: tTest of a Mean
 Data is weighted: Complex Samples tTest of a Mean
If Means = zTest:

 Data is not weighted: ZTest of a Mean
 Data is weighted: Complex Samples ZTest of a Mean
If Means = tTest:

 Data is not weighted: tTest of a Mean
 Data is weighted: Complex Samples tTest of a Mean
If Means = Quantum Means or Survey Reporter Means: Quantum and Survey Reporter tTest of a Mean
Each of these tests has an expected value,\(e\), as an input. For Number  Grid questions: \(e\) is computed by multiplying the average for the row with the average for the column and dividing by the overall table average (excluding cells for which Not Duplicate is 0). In most other instances it is the average of all the cells or 0 (the expected value is shown in the results of a Planned Tests Of Statistical Significance).