Development and initial validation of the Localized Scleroderma Skin Damage Index and Physician Global Assessment of disease Damage: a proof-of-concept study

作者：Arkachaisri Thaschawee^*; Vilaiyuk Soamarat; Torok Kathryn S; Medsger Thomas A Jr

来源：Rheumatology, 2010, 49(2): 373-381.

DOI：10.1093/rheumatology/kep361

• Localized scleroderma
• Outcome measures
• Damage index
• Global assessment

Objective. To develop and assess the psychometric properties of the Localized Scleroderma (LS) Skin Damage Index (LoSDI) and Physician Global Assessment of disease Damage (PGA-D).
Methods. Damage was defined as irreversible/persistent changes (>6 months) due to previous active disease/complications of therapy. Eight rheumatologists assessed the importance of 17 variables in formulating the PGA-D/LoSDI. LS patients were evaluated by two rheumatologists using both tools to assess their psychometric properties. LoSDI was calculated by summing three scores for cutaneous features of damage [dermal atrophy (DAT), subcutaneous atrophy (SAT) and dyspigmentation (DP)] measured at 18 anatomic sites. Patient GA of disease severity (PtGA-S), Children's Dermatology Life Quality Index (CDLQI) and PGA-D were recorded at the time of each examination.
Results. Thirty LS patients (112 lesions) and nine patient-visit pairs (18 lesions) were included for inter-and intra-rater reliability study. LoSDI and its domains DAT, SAT, DP and PGA-D demonstrated excellent inter-and intra-rater reliability (reliability coefficients 0.86-0.99 and 0.74-0.96, respectively). LoSDI correlated moderately with PGA-D and poorly with PtGA-S and CDLQI. PGA-D correlated moderately with PtGA-S, but poorly with CDLQI.
Conclusions. To complete the LS Cutaneous Assessment Tool (LoSCAT), we developed and evaluated the psychometric properties of the LoSDI and PGA-D in addition to the LS Skin Severity Index (LoSSI). These instruments will facilitate evaluation of LS patients for individual patient management and clinical trials. LoSDI and PGA-D demonstrated excellent reliability and high validity. LoSCAT provides an improved understanding of LS natural history. Further study in a larger group of patients is needed to confirm these preliminary findings.

• 出版日期2010-2