The Psoriasis Epidemiology Screening Tool (PEST) is a validated screening tool for psoriatic arthritis . It is recommended that individuals with psoriasis complete the PEST every six months. Forty-one percent of those who screened positive for PsA using the PEST had not previously been diagnosed with PsA.
Screen for PsA
One in three individuals with psoriasis have PsA. 
Psoriatic arthritis (PsA) is a common comorbidity of psoriasis. PsA can lead to permanent damage to bones and joints, especially if untreated. Currently, no diagnostic test for PsA exists. Thankfully, validated screening tools exist to help identify signs and symptoms of the disease.
Take the PsA Screener
A five question Psoriasis Epidemiology Screening Tool (PEST)
1. Mease PJ, Gladman DD, Papp KA, et al. Prevalence of rheumatologist-diagnosed psoriatic arthritis in patients with psoriasis in European/North American dermatology clinics. J Am Acad Dermatol. 2013;69(5):729-35. doi: 10.1016/j.jaad.2013.07.023.
2. Ibrahim GH, Buch MH, Lawson C, et al. Evaluation of an existing screening tool for psoriatic arthritis in people with psoriasis and the development of a new instrument: the Psoriasis Epidemiology Screening Tool (PEST) questionnaire. Clin Exp Rheumatol. 2009;27(3):469-74. PMID: 19604440.