A clinical psychologist is investigating whether a mindfulness smartphone app reduces anxiety in patients diagnosed with mild generalized anxiety disorder. A sample of patients have their self-reported anxiety level assessed on a scale of 1 to 50 (with higher scores indicating greater anxiety) both before using the app for a month (Pre-treatment) and after a month of daily app usage (Post-treatment). The differences in scores between the two conditions are found to be non-normally distributed.
Identify the statistical test that should be used to analyse the data from this study. Give three reasons for your choice of test.
121 exam-style questions on AQA A Level Psychology Inferential testing (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.