BACKGROUND: Tools to measure and to monitor the severity of psoriasis over time are needed for research and for patient care. Hence reliability is essential to document the response to the treatment. This study is done to compare the reliability of PASI, PGA x BSA and SPASI in 100 psoriasis patients.

OBJECTIVE:   We sought to evaluate the effectiveness of PASI (Psoriasis Area and Severity Index), SPASI (simplified PASI) and PGA x BSA (Physician Global Assessment and Body Surface Area) in grading the severity of psoriasis.

METHODS: A cross sectional study was done with 100 patients diagnosed with psoriasis (all types). All the patients were subjected to complete history, complete physical and dermatological examination and scoring using PASI, SPASI and PGA x BSA.

RESULTS: In our study on comparing PASI, PGA x BSA and SPASI, the coefficient of variation was low in SPASI (80.27), followed by PGA x BSA (93.73) and PASI (122.30). Thus SPASI can be a simplified scoring for measuring psoriasis in the day to day practice.

CONCLUSION: Several scoring systems are available to evaluate the severity of psoriasis. Because PASI is better studied and elaborated, it remains the score of choice for clinical trials, but the simpler SPASI and PGA may be used in day to day practice.