title: Validity and Reliability of Dermoscopic Criteria Used to Differentiate Nevi From Melanoma: A Web-Based International Dermoscopy Society Study.
abstract: The comparative diagnostic performance of dermoscopic algorithms and their individual criteria are not well studied.
  
  
  
  To analyze the discriminatory power and reliability of dermoscopic criteria used in melanoma detection and compare the diagnostic accuracy of existing algorithms.
  
  
  
  This was a retrospective, observational study of 477 lesions (119 melanomas [24.9%] and 358 nevi [75.1%]), which were divided into 12 image sets that consisted of 39 or 40 images per set. A link on the International Dermoscopy Society website from January 1, 2011, through December 31, 2011, directed participants to the study website. Data analysis was performed from June 1, 2013, through May 31, 2015. Participants included physicians, residents, and medical students, and there were no specialty-type or experience-level restrictions. Participants were randomly assigned to evaluate 1 of the 12 image sets.
  
  
  
  Associations with melanoma and intraclass correlation coefficients (ICCs) were evaluated for the presence of dermoscopic criteria. Diagnostic accuracy measures were estimated for the following algorithms: the ABCD rule, the Menzies method, the 7-point checklist, the 3-point checklist, chaos and clues, and CASH (color, architecture, symmetry, and homogeneity).
  
  
  
  A total of 240 participants registered, and 103 (42.9%) evaluated all images. The 110 participants (45.8%) who evaluated fewer than 20 lesions were excluded, resulting in data from 130 participants (54.2%), 121 (93.1%) of whom were regular dermoscopy users. Criteria associated with melanoma included marked architectural disorder (odds ratio [OR], 6.6; 95% CI, 5.6-7.8), pattern asymmetry (OR, 4.9; 95% CI, 4.1-5.8), nonorganized pattern (OR, 3.3; 95% CI, 2.9-3.7), border score of 6 (OR, 3.3; 95% CI, 2.5-4.3), and contour asymmetry (OR, 3.2; 95% CI, 2.7-3.7) (P < .001 for all). Most dermoscopic criteria had poor to fair interobserver agreement. Criteria that reached moderate levels of agreement included comma vessels (ICC, 0.44; 95% CI, 0.40-0.49), absence of vessels (ICC, 0.46; 95% CI, 0.42-0.51), dark brown color (ICC, 0.40; 95% CI, 0.35-0.44), and architectural disorder (ICC, 0.43; 95% CI, 0.39-0.48). The Menzies method had the highest sensitivity for melanoma diagnosis (95.1%) but the lowest specificity (24.8%) compared with any other method (P < .001). The ABCD rule had the highest specificity (59.4%). All methods had similar areas under the receiver operating characteristic curves.
  
  
  
  Important dermoscopic criteria for melanoma recognition were revalidated by participants with varied experience. Six algorithms tested had similar but modest levels of diagnostic accuracy, and the interobserver agreement of most individual criteria was poor.
authors.affiliation: Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York2Melanoma Unit, Department of Dermatology, Hospital Clinic Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona.
authors.forename: Cristina
authors.initials: C
authors.lastname: Carrera
authors.affiliation: Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Marchetti
authors.affiliation: Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Dusza
authors.affiliation: Dermatology Unit, Second University of Naples, Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Argenziano
authors.affiliation: Department of Dermatology, University Hospital Zürich, Zürich, Switzerland.
authors.forename: Ralph P
authors.initials: RP
authors.lastname: Braun
authors.affiliation: Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Allan C
authors.initials: AC
authors.lastname: Halpern
authors.affiliation: Dermatology Service, Aurora Skin Cancer Center, Universidad Pontificia Bolivariana, Medellín, Colombia.
authors.forename: Natalia
authors.initials: N
authors.lastname: Jaimes
authors.affiliation: Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Harald J
authors.initials: HJ
authors.lastname: Kittler
authors.affiliation: Melanoma Unit, Department of Dermatology, Hospital Clinic Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Centro de Investigacion Biomedica en red de enfermedades raras, Barcelona, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Malvehy
authors.affiliation: Sydney Melanoma Diagnostic Centre, Sydney Cancer Centre, Royal Prince Alfred Hospital, Camperdown, Australia8Discipline of Dermatology, The University of Sydney, New South Wales, Australia.
authors.forename: Scott W
authors.initials: SW
authors.lastname: Menzies
authors.affiliation: Center for Environmental, Genetic, and Nutritional Epidemiology, Department of Diagnostic, Clinical, and Public Health Medicine, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pellacani
authors.affiliation: Melanoma Unit, Department of Dermatology, Hospital Clinic Barcelona, Institut d'Investigacions Biomèdiques August Pi i Sunyer, University of Barcelona, Centro de Investigacion Biomedica en red de enfermedades raras, Barcelona, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Puig
authors.affiliation: Skin and Cancer Associates, Plantation, Florida.
authors.forename: Harold S
authors.initials: HS
authors.lastname: Rabinovitz
authors.affiliation: Department of Dermatology, Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Alon
authors.initials: A
authors.lastname: Scope
authors.affiliation: Dermatology Research Centre, The University of Queensland, Brisbane, Queensland, Australia13School of Medicine, Translational Research Institute, Brisbane, Queensland, Australia.
authors.forename: H Peter
authors.initials: HP
authors.lastname: Soyer
authors.affiliation: Clinic for Dermatology, Allergology, and Environmental Medicine, Klinik Thalkirchner Straße Städt, Klinikum München GmbH, Munich, Germany.
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Stolz
authors.affiliation: Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Rainer
authors.initials: R
authors.lastname: Hofmann-Wellenhof
authors.affiliation: Department of Dermatology, Medical University of Graz, Graz, Austria.
authors.forename: Iris
authors.initials: I
authors.lastname: Zalaudek
authors.affiliation: Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York.
authors.forename: Ashfaq A
authors.initials: AA
authors.lastname: Marghoob
mesh_terms: D000465:Algorithms; D046169:Dermoscopy; D003937:Diagnosis, Differential; D006801:Humans; D020407:Internet; D008545:Melanoma / Q000000981:diagnostic imaging*; D009506:Nevus / Q000000981:diagnostic imaging*; D015588:Observer Variation; D012372:ROC Curve; D011897:Random Allocation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000000981:diagnostic imaging*