Translation and validation of the Simplified Psoriasis Index (SPI) into Brazilian Portuguese

BACKGROUND: The Simplified Psoriasis Index is a tool that assesses the current severity, psychosocial impact, past history and interventions in patients with psoriasis through separate components. Two versions are available, one in which the current severity of the disease is evaluated by the patient themselves and another by the physician. OBJECTIVES: Translate the Simplified Psoriasis Index into Brazilian Portuguese and verify its validity. METHODS: The study was conducted in two stages; the first stage was the translation of the instrument; the second stage was the instrument's validation. RESULTS: We evaluated 62 patients from Complexo Hospitalar Santa Casa de Porto Alegre and Hospital Universitario de Brasilia. The Simplified Psoriasis Index translated into Portuguese showed high internal consistency (Cronbach test 0.68). STUDY LIMITATIONS: Some individuals, because of poor education, might not understand some questions of the Simplified Psoriasis Index. CONCLUSIONS: The Brazilian Portuguese version of the Simplified Psoriasis Index was validated for our population and can be recommended as a reliable instrument to assess the patients with psoriasis.