title: Evaluation of internal consistency of the epidermolysis bullosa oropharyngeal severity score (EBOS).
abstract: OBJECTIVE
  To evaluate the internal consistency of the epidermolysis bullosa oropharyngeal severity score (EBOS).
  
  
  METHODS
  Data from 92 patients of varying EB types/sub-types already described in a previous multi-center study were re-analyzed via the coefficient Cronbach's α (CR-α). Additionally, the corrected item total correlation between each item and the items' overall score with Pearson's product-moment correlation (ρ) was calculated.
  
  
  RESULTS
  The alpha coefficient for the mean total score of 17 items is 0.941. The inter-observer reliability for disease severity score was excellent for oral medicine specialist (α = 0.924) and dermatologist (α = 0.916) and the intra-observer reliability was good at Time 1 (α = 0.895) and Time 2 (α = 0.897). The analysis of CR-α per single item revealed that alpha was greater than 0.904 for disease activity and 0.743 for structural damage, after the elimination of four items for oral medicine specialist and greater than 0.898 for disease activity and 0.769 for structural damage after the elimination of five items for dermatologist. Similarly the analysis of the corrected items-EBOS correlation showed that the same items do not correlate very well (ρ < 0.4) with the overall EBOS.
  
  
  CONCLUSIONS
  The EBOS turned out to have a strong and reliable internal consistency, as the majority of the EBOS' items were consistent with each other.
authors.affiliation: Department of Oral Medicine, Carolinas Medical Center , Charlotte, NC , USA.
authors.forename: Giulio
authors.initials: G
authors.lastname: Fortuna
authors.forename: Massimo
authors.initials: M
authors.lastname: Aria
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Cepeda-Valdes
authors.forename: Julio Cesar
authors.initials: JC
authors.lastname: Salas-Alanís
mesh_terms: D003744:Dental Enamel Hypoplasia / Q000145:classification; D003880:Dermatology; D004820:Epidermolysis Bullosa / Q000145:classification*; D006801:Humans; D009060:Mouth Floor / Q000473:pathology; D015588:Observer Variation; D019242:Oral Medicine; D009960:Oropharynx / Q000473:pathology*; D010608:Pharyngeal Diseases / Q000145:classification*; D015203:Reproducibility of Results; D012720:Severity of Illness Index
keywords: EB; consistency; reliability; score; validity