Hauspy 2007.

Study characteristics
Patient sampling	Prospective study; consecutive enrolment; 42 recruited; 1 exclusion
Patient characteristics and setting	41 women with vulval cancer (39 SCC, 2 melanomas) at clinical stages T1/2 (68 groins). It is unclear whether any stage IA lesions were included 11 women had lateralised lesions and 30 had midline or near midline lesions No palpable nodes Median age: 65 years (34 to 94) Setting: a tertiary institution in Canada from April 2004 to September 2006
Index tests	SN detection by Tc‐99m with or without blue dye Histological methods: frozen section and ultrastaging was performed for SNs with H&E and IHC stains; standard sections with H&E stains were performed for other nodes (RS)
Target condition and reference standard(s)	TC: groin lymph node involvement RS: complete IFL
Flow and timing	Tc‐99m (0.1 to 0.2 mCi) was injected intradermally 2 to 4 hours pre‐operatively in 2 to 4 sites around the primary lesion, with or without up to 4 ml blue dye injected intradermally at the start of surgery. The node was considered 'hot' if radioactivity was 5 x background activity SND and RS were performed during the same operation 1 withdrawal described
Comparative
Notes	At the beginning of the study, all women received both Tc‐99m and blue dye, but later on blue dye was only used if the initial Tc‐99m test failed to identify SNs. Thus, combined tests and Tc‐99m only tests were used in 30 and 11 women, respectively. We were unable to extract separate 2 x 2 data for the combined and single techniques Participants were stratified by the proximity of the lesion to the midline (midline; ≤ 1 cm of midline; lateralised)
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?	Yes
		Low	Unclear
DOMAIN 2: Index Test Test group
Had the test operator performed 10 or more procedures?	Unclear
		Unclear	Low
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
		Unclear	Low
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
Were other imaging tests performed prior to the index test to rule out groin lymph node metastases?	Unclear
		Unclear