A psychologist investigates whether a mindfulness intervention reduces anxiety levels in a cohort of university students. Anxiety is measured using a standardised scale that yields interval-level data, and the scores are normally distributed. Each participant's anxiety level is measured before the intervention and after completing the 6-week programme. Which inferential statistical test should be used to analyse whether there is a significant reduction in anxiety?
Wilcoxon Signed Ranks test
Related ttt-test
Unrelated ttt-test
Sign test
