[French adaptation of a new score for global assessment of psoriasis severity: The Simplified Psoriasis Index (SPI)]

Objective: Although several scores exist to assess psoriasis severity, most have marked limitations that rule out their use in routine clinical practice. A new score, the Simplified Psoriasis Index (SPI), has recently been developed and validated in adults in Britain for such use. It has separate components for current severity (SPI-s), psychosocial impact (SPI-p) and past history and interventions (SPI-p), and it is suitable for either professional assessment or patient self-assessment. The aim of this work was to produce a validated translation of SPI into French (as spoken in France).

Methods: The index was translated and validated using a strict methodology comprising respectively five and eight phases for the professional (proSPI) and self-administered instruments (saSPI). Translation of the saSPI instrument also involved a cognitive debriefing with five psoriasis patients.

Results: Linguistic discrepancies and subtle differences of meaning arising during the process were closely examined. The developer of the instrument ensured conceptual accuracy. A panel of health experts guaranteed that medical terms were correctly translated. Five patients with plaque psoriasis (two female and three male of median age 45 years [range: 31-78]) tested the SPI-p version during cognitive interviews and found the questionnaire clear and easy to understand.

Conclusion: Validated French translations of both SPI instruments are now available for use in routine clinical practice. Further investigations are currently underway to validate the psychometric properties of the instrument.