The dependent-samples t-test (also called related-samples t-test or paired t-test) is for comparing conditions that have related participants. The most common use would be to compare a "pre", baseline condition to a "post" measurement after an intervention.
*** Waiting for results ***
Notes: The values need to be in pairs, like X1 and X2 are from the same person. The difference scores are calculated as post - pre scores (X2 - X1). This makes the sign of the t-test match the direction of the change over time: lower scores over time have negative t scores and vice versa.
Creative Commons Attribution 4.0 International License that allows sharing, adapting, and remixing.