A Clinical Researcher Was Interested in Determining Whether Her Interventions

Multiple Choice

A clinical researcher was interested in determining whether her interventions for depression were effective in minimizing depression symptoms among her participants.To assess the effectiveness of her treatment program, she administered a depression inventory prior to treatment and after treatment.She hypothesized that depression scores would be lower at time two compared to time one.She then compared the mean differences between the two groups and found that her treatment was effective.Which statistical test was the researcher MOST likely to have used to test her hypothesis?

A) single-sample t test
B) z test
C) independent-samples t test
D) paired-samples t test