Phase II clinical study

Consider a clinical study on rumination-focused Cognitive Behavioral Therapy (rfCBT) with N=31 patients. The primary outcome is the score on the Hamilton Rating Scale for Depression (HDRS, range from best = 0 to worst = 42). The significance level is set to α=5% two-tailed.

Table 1. Observed HDRS scores at T0, EOT, and D=T0-EOT
HDRST0EOTD
Average28.824.04.8
SD8.39.73.6