Blum 2003b.

Study characteristics
Patient sampling	Study design: case series Data collection: retrospective image selection/prospective interpretation Period of data collection: September 1998‐December 1999; lesions overlap with Blum 2004b; data only included in algorithm comparison and not in primary analysis. Country: Germany
Patient characteristics and setting	Inclusion criteria: all lesions of patients with multiple atypical naevi excised due to suspicious clinical and/or dermoscopic features were included Setting: specialist unit (skin cancer/PLC) Prior testing: clinical and/or dermatoscopic suspicion Setting for prior testing: specialist unit (skin cancer/PLC) Exclusion criteria: lesions located on soles, palms, subungual and mucosal sites were excluded Sample size (participants): number included: 205 Sample size (lesions): number eligible: 254/number included: 254 Participant characteristics: median age: 39.2 (1.6‐86.4 years); male: 97 (47.3%) Lesion characteristics: NR
Index tests	Dermoscopy: new algorithm (based on criteria of Hofmann‐Wellenhof 2001) Method of diagnosis: dermoscopic images Prior test data: unclear; looks like blinded test interpretation Diagnostic threshold: lesions were classified into six different types according to morphological criteria of the new classification of atypical naevi (Clark naevi): reticular, globular and homogeneous or combinations of two of these types (Hofmann‐Wellenhof 2001). If reticular, globular and homogeneous structures were found in one melanocytic lesion, this lesion was classified as a 3‐structure type Diagnosis based on: consensus (2 observers); n = 2 Observer qualifications: NR; likely dermatologists, "All images were viewed by two investigators" Experience in practice: not described Experience with dermoscopy: not described
Target condition and reference standard(s)	Reference standard: histological diagnosis alone Disease‐positive: 75 MM; disease‐negative: 179 Target condition (final diagnoses) Melanoma (invasive): 63; melanoma (in situ): 12 Benign naevus: recurrent naevus 6; SN or Reed naevus 6; congenital naevus 4; blue naevus 3; naevus without dysplasia 64; dysplastic naevus 96
Flow and timing	Excluded participants: none reported Time interval between index and reference: assumed consecutive, "All patients gave written informed consent for the digital documentation and the following operation under local anaesthesia"
Comparative
Notes	‐
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Yes
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	No
Are the included patients and chosen study setting appropriate?	No
Did the study avoid including participants with multiple lesions?	No
		High	High
DOMAIN 2: Index Test Dermoscopy ‐ image‐based
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
If a threshold was used, was it pre‐specified?	No
For studies reporting the accuracy of multiple diagnostic thresholds, was each threshold or algorithm interpreted without knowledge of the results of the others?
Was the test applied and interpreted in a clinically applicable manner?	No
Were thresholds or criteria for diagnosis reported in sufficient detail to allow replication?	Yes
Was the test interpretation carried out by an experienced examiner?	Unclear
		High	High
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	Unclear
Expert opinion (with no histological confirmation) was not used as a reference standard	Yes
Was histology interpretation carried out by an experienced histopathologist or by a dermatopathologist?	Unclear
		Low	Unclear
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
If the reference standard includes clinical follow‐up of borderline/benign appearing lesions, was there a minimum follow‐up following application of index test(s) of at least: 3 months for melanoma or cSCC or 6 months for BCC?
If more than one algorithm was evaluated for the same test, was the interval between application of the different algorithms 1 month or less?	Yes
		Low