A multi-item Physician Global Assessment scale to assess psoriasis disease severity: validation based on four phase III tofacitinib studies

Table 2 Known-group validity of the PGA

Category definition based on the PASI score	Mean difference in PGA scores between group with PASI score = 0 and indicated PASI score group^*	95% CI
Category definition based on the PASI score		Lower	Higher
0 < PASI ≤ 5	−1.01	−1.04	−0.98
5 < PASI ≤ 10	−1.61	−1.65	−1.58
10 < PASI ≤ 20	−2.41	−2.44	−2.37
20 < PASI ≤ 30	−2.92	−2.96	−2.89
30 < PASI ≤ 40	−3.27	−3.31	−3.23
40 < PASI ≤ 72	−3.67	−3.73	−3.61

^*All p-values ≤0.0001 vs group with PASI score = 0
PGA score was outcome and PASI score was categorical anchor, with no functional relationship imposed
CI confidence interval, PASI Psoriasis Area and Severity Index, PGA Physician Global Assessment

ISSN: 1471-5945