The purpose of this study is to conduct full psychometric testing of the Early Arthritis for Psoriatic Patients (EARP) questionnaire in Australian, Korean and Chinese populations

This is a multicentre, observational, descriptive estimate of the proportion of participants with psoriatic arthritis among psoriasis participants attending dermatology clinics selected for this study. In addition, this study will involve full psychometric assessment of the Early psoriatic screening questionnaire (EARP) questionnaire with the aim of identifying and appropriately referring participants to a rheumatologist for review if their EARP score is 3 or greater at Screening (i.e. >= 3 at Visit 1).

Inclusion Criteria:

• Patient must be a man or woman aged 18 to 65 years of age, inclusive
• The patient must have an established diagnosis of psoriasis (based upon clinical evidence, and documented medical history [19])
• The patient must be able to read and write in the target language (English, Mandarin or Korean; or other relevant target languages)
• Each patient must sign an informed consent form (ICF) indicating that he or she understands the purpose of and procedures required for the study and are willing to participate in the study

Exclusion Criteria:

• An established diagnosis of psoriatic arthritis
• Ever have received systemic treatment with a disease modifying antirheumatic drug (DMARD) for arthritis or spondylitis (inflammatory back pain)
• Ever have received systemic treatment with a biologic therapy for psoriasis (including infliximab, golimumab, ustekinumab, adalimumab or etanercept)
• A history of employment in or are currently employed in the healthcare industry; or
• Participated in the translation and linguistic validation of the EARP questionnaire

Participants with psoriatic arthritis among psoriasis participants attending dermatology clinics.