Based on this systematic review, it appears that none of the severity scores used for psoriasis meets all of the validation criteria required for an ideal score. However, we can conclude that the PASI score is the most extensively studied psoriasis clinical severity score and the most thoroughly validated according to methodological validation criteria. Despite certain limitations, use of the PASI score can be recommended for scientific evaluation of the clinical severity of psoriasis.

There is an increased risk of obesity and metabolic syndrome in psoriasis. For hypertension, diabetes and dyslipidaemia no consistency was found across studies. Prospective epidemiological studies with thorough recording of cardiovascular risk factors are required in psoriasis patients.

On the basis of this systematic review, we can conclude that the DLQI is easy to use in clinical practice because of its brevity and simplicity. SF36 is widely used in clinical trials. Skindex 29 and Skindex 17, although rarely used, are interesting because of their cross-cultural validation.

Psoriasis arthritis may affect up to 24% of psoriasis patients. Dermatologist should be aware of main clinical sign of PsA to promote earlier recognition and treatment of PsA.

Ten recommendations to assess the severity of plaque-type psoriasis in adult patients in daily practice were developed. The recommendations are based on systematic appraisal of available evidence. They were developed and supported by a panel of dermatologists, which enhances their validity and practical relevance.