Abstract
In psoriasis treatment, there is a high need to define meaningful endpoints and differences from the patient perspective to analyze patient-relevant differences of frequently used outcome methods for psoriasis under real-world conditions. A sample of 3116 patients from the German Psoriasis-Registry PsoBest was analyzed for clinical as well as patient-reported outcomes (PRO) after 3- and 6-month treatment. The parameters PASI, DLQI, and PBI were intercorrelated and related to two anchoring variables: (1) patient satisfaction with treatment and (2) perceived complete clearance. Baseline data were as follows: PASI 10.5 ± 9.1, DLQI 12.4 ± 3.4, and PBI 2.7 ± 0.3. There was an almost linear relationship between "complete patient satisfaction" and the relative differences in PASI in the range from PASI 25 to PASI 90. However, there was no additional benefit between PASI 90 and PASI 100. The same finding resulted from the anchoring variable "perception of complete healing". When related to DLQI outcomes, relative PASI changes as well as absolute changes and PASI at 3 and 6 months showed relevant differences between the PASI classes 25 to 90 but not between PASI 90 and PASI 100. Under real-world conditions, changes in PASI and DLQI reflect patient-relevant benefits.