RESUMEN
BACKGROUND AND OBJECTIVE: The Simplified Psoriasis Index (SPI) is a recently validated tool in Spanish that measures psoriasis severity by integrating 3 different spheres: clinical severity (SPI-s), psychosocial impact (SPI-p), and natural history (SPI-i). Our objective was to study the validity and equivalence of this new scale compared to routinely used scales such as the Psoriasis Area and Severity Index, PASI, and the Dermatology Life Quality Index (DLQI). MATERIALS AND METHODS: This was a cross-sectional and observational study that included 45 patients aged 18 to 74 years. Demographic data and information associated with psoriasis severity and the patients' quality of life were collected, using PASI, DLQI, and SPI simultaneously. The correlation of reference scales (PASI and DLQI) with SPI was examined. The degree of agreement between the 2 versions of SPI completed by the physician (proSPI-s) and self-administered by the patient (saSPI-s), was also studied. RESULTS: The mean age of the study population was 51 years, with a mean psoriasis history of 14.05 years. A strong correlation was found between PASI and proSPI-s (r=0.89), as well as between DLQI and SPI-p (r=0.89), with a moderate correlation being reported between PASI and saSPI-s (r=0.52). The degree of agreement between proSPI-s and saSPI-s was moderate. CONCLUSIONS: These findings represent the initial results of real clinical practice using the validated Spanish version of SPI, making its use truly promising in the routine clinical practice.
