title: Development of a clinical diagnostic matrix for characterizing inherited epidermolysis bullosa.
abstract: BACKGROUND
  Accurately diagnosing the subtype of epidermolysis bullosa (EB) is critical for management and genetic counselling. Modern laboratory techniques are largely inaccessible in developing countries, where the diagnosis remains clinical and often inaccurate.
  
  
  OBJECTIVE
  To develop a simple clinical diagnostic tool to aid in the diagnosis and subtyping of EB.
  
  
  METHODS
  We developed a matrix indicating presence or absence of a set of distinctive clinical features (as rows) for the nine most prevalent EB subtypes (as columns). To test an individual patient, presence or absence of these features was compared with the findings expected in each of the nine subtypes to see which corresponded best. If two or more diagnoses scored equally, the diagnosis with the greatest number of specific features was selected. The matrix was tested using findings from 74 genetically characterized patients with EB aged > 6 months by an investigator blinded to molecular diagnosis. For concordance, matrix diagnoses were compared with molecular diagnoses.
  
  
  RESULTS
  Overall, concordance between the matrix and molecular diagnoses for the four major types of EB was 91·9%, with a kappa coefficient of 0·88 [95% confidence interval (CI) 0·81-0·95; P < 0·001]. The matrix achieved a 75·7% agreement in classifying EB into its nine subtypes, with a kappa coefficient of 0·73 (95% CI 0·69-0·77; P < 0·001).
  
  
  CONCLUSIONS
  The matrix appears to be simple, valid and useful in predicting the type and subtype of EB. An electronic version will facilitate further testing.
authors.affiliation: Department of Dermatology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: V K
authors.initials: VK
authors.lastname: Yenamandra
authors.affiliation: Department of Dermatology, Birmingham Children's Hospital, Birmingham, U.K.
authors.forename: C
authors.initials: C
authors.lastname: Moss
authors.affiliation: Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: V
authors.initials: V
authors.lastname: Sreenivas
authors.affiliation: Sadd Maareb Medical Centre, Abu Dhabi, U.A.E.
authors.forename: M
authors.initials: M
authors.lastname: Khan
authors.affiliation: CSIR-Institute of Genomics and Integrative Biology, New Delhi, India.
authors.forename: S
authors.initials: S
authors.lastname: Sivasubbu
authors.affiliation: Department of Dermatology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: V K
authors.initials: VK
authors.lastname: Sharma
authors.affiliation: Department of Dermatology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: G
authors.identifier: http://orcid.org/0000-0003-4114-8952
authors.initials: G
authors.lastname: Sethuraman
mesh_terms: D002648:Child; D002675:Child, Preschool; D004820:Epidermolysis Bullosa / Q000175:diagnosis* / Q000235:genetics; D005240:Feasibility Studies; D006801:Humans; D010865:Pilot Projects; D019095:Point-of-Care Systems; D011446:Prospective Studies