title: Reliability testing of the dermatology index of disease severity (DIDS). An index for staging the severity of cutaneous inflammatory disease.
abstract: OBJECTIVE
  To describe a new severity of illness index for inflammatory skin disease called the Dermatology Index of Disease Severity (DIDS), and to show its preliminary use and reliability in staging disease in patients with psoriasis and dermatitis.
  
  
  METHODS
  Interobserver rating study using the DIDS with as many as 10 observers independently rating the same patient at a single point in time.
  
  
  METHODS
  Ambulatory care clinics at an academic medical center with patients from various socioeconomic backgrounds.
  
  
  METHODS
  Thirty-four patients with psoriasis and 15 patients with dermatitis were included in the study.
  
  
  METHODS
  The severity of illness for each patient was rated as 1 of 5 stages: 0, no evidence of clinical disease; I, limited disease; II, mild disease; III, moderate disease; and IV, severe disease. The degree of interobserver concordance was measured by the Cohen kappa statistic.
  
  
  RESULTS
  All 5 stages were represented in the study of patients with psoriasis. The overall kappa statistic was 0.76, which is defined as substantial interobserver concordance. The use of the instrument in dermatitis showed good consensus in staging, where the kappa statistic was 0.41.
  
  
  CONCLUSIONS
  We introduce an easy and efficient instrument for staging the severity of illness in inflammatory cutaneous diseases. The reliability of the DIDS is demonstrated in patients with psoriasis and in patients with dermatitis.
authors.affiliation: Department of Dermatology, Indiana University Medical Center, Indianapolis, USA.
authors.forename: H B
authors.initials: HB
authors.lastname: Faust
authors.forename: R
authors.initials: R
authors.lastname: Gonin
authors.forename: T Y
authors.initials: TY
authors.lastname: Chuang
authors.forename: C W
authors.initials: CW
authors.lastname: Lewis
authors.forename: C A
authors.initials: CA
authors.lastname: Melfi
authors.forename: E R
authors.initials: ER
authors.lastname: Farmer
mesh_terms: D000328:Adult; D003872:Dermatitis / Q000175:diagnosis*; D006801:Humans; D011565:Psoriasis / Q000175:diagnosis*; D015203:Reproducibility of Results; D012720:Severity of Illness Index