It has to be interpreted as a continuous variable. The test is done using a t-test inside the glm. This reduces to a Pearson if there is only one variable and no intercept (which it is not).
doug
Xie, Hong wrote:
Hello, freesurfer group,
I have run qdec for comparing thickness between two groups. When qdec does a correlation analyses for thickness versus a second variable: 1) Does the second variable have to be a continuous interval variable or 2) can the second variable be an ordinal variable with more than 2 levels? In the case of the correlation between two continuous variable, is the test a Pearson correlation? If 2) is possible, is the correlation a Spearman correlation?
Thank for your help,
Hong Xie
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