title: Preliminary validation and clinical meaning of the Cutaneous Assessment Tool in juvenile dermatomyositis.
abstract: OBJECTIVE
  To provide preliminary validation of the Cutaneous Assessment Tool (CAT), a new tool to assess cutaneous manifestations of juvenile dermatomyositis (DM), and to explore the clinical meaning of CAT scores.
  
  
  METHODS
  Children with juvenile DM (n = 113) were assessed at baseline and 7-9 months later (n = 94). Internal consistency, redundancy, construct validity, and responsiveness of the CAT were examined. CAT scores corresponding to ordinal global assessments were determined.
  
  
  RESULTS
  Item-total correlations ranged from 0.27-0.67 for activity lesions present in > or =10% of patients; item-domain and domain-total correlations ranged from 0.25-0.99. Cronbach's alpha was 0.79 for the CAT activity score and 0.74 for the CAT damage score. As predicted, the CAT activity score correlated strongly with both global disease activity and skin disease activity and moderately with the Childhood Myositis Assessment Scale, whereas the CAT damage score correlated moderately with the physician global disease and skin disease damage scores. Median CAT activity scores of 1, 7, 13, 18, and 31 corresponded to absent, mild, moderate, severe, and extremely severe skin disease activity, respectively. Median CAT damage scores of 0, 1, 2, and 5 correlated with the same descriptions of damage (severe and extremely severe combined).
  
  
  CONCLUSIONS
  Preliminary validation of the CAT demonstrated good internal consistency, nonredundancy, good construct validity, and appropriate responsiveness. The CAT is a comprehensive, semiquantitative assessment tool for skin disease in juvenile DM.
authors.affiliation: Division of Pediatric Rheumatology,IWK Health Centre and Dalhousie University, Halifax, Nova Scotia, Canada. adam.huber@iwk.nshealth.ca
authors.forename: Adam M
authors.initials: AM
authors.lastname: Huber
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Dugan
authors.forename: Peter A
authors.initials: PA
authors.lastname: Lachenbruch
authors.forename: Brian M
authors.initials: BM
authors.lastname: Feldman
authors.forename: Maria D
authors.initials: MD
authors.lastname: Perez
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Zemel
authors.forename: Carol B
authors.initials: CB
authors.lastname: Lindsley
authors.forename: Robert M
authors.initials: RM
authors.lastname: Rennebohm
authors.forename: Carol A
authors.initials: CA
authors.lastname: Wallace
authors.forename: Murray H
authors.initials: MH
authors.lastname: Passo
authors.forename: Ann M
authors.initials: AM
authors.lastname: Reed
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Bowyer
authors.forename: Susan H
authors.initials: SH
authors.lastname: Ballinger
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Miller
authors.forename: Lisa G
authors.initials: LG
authors.lastname: Rider
mesh_terms: D000208:Acute Disease; D002648:Child; D002908:Chronic Disease; D003882:Dermatomyositis / Q000473:pathology* / Q000503:physiopathology*; D005500:Follow-Up Studies; D006801:Humans; D009220:Myositis / Q000175:diagnosis / Q000503:physiopathology; D010865:Pilot Projects; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012867:Skin / Q000473:pathology