Li 2012a.

Study characteristics
Patient sampling	Retrospective? consecutive?patient series
Patient characteristics and setting	80 patients, mean age = 58 (range = 35‐84) years, 52 males/28 females, China Histology of primary tumour: Not reported. Comorbidities: Not reported. Inclusion criteria: Patients with NSCLC who underwent curative surgical resection with regional lymph node dissection after 18F‐FDG PET/CT and breath‐hold spiral CT between October 2006 and March 2009. Exclusion criteria: None listed. Previous/all tests : Not reported. Clinical setting: Secondary/tertiary setting The inclusion criteria narrows the range of patients who would receive PET‐CT in practice, namely, patients (clinically) with suspected resectable non‐small cell lung cancer, a proportion of whom would have N2 or N3 disease on PET‐CT
Index tests	FDG PET‐CT were acquired on an integrated PET‐CT device (GE Discovery ST16) that consisted of a PET scanner and a 16‐slice CT scanner. The participants fasted for ≥ 6 hours, and after a normal blood glucose level was ensured (≤ 8 mmol/L), received an intravenous injection of FDG 3.7 to 4.44 MBq/kg and then rested for 50 to 70 min before undergoing the scan. 2 chest radiologists with PET‐CT diagnostic experience evaluated the PET‐CT datasets. Nodal status was determined by SUV associated with CT attenuation. Additionally, if FDG uptake was positive, lymph nodes with calcification or higher attenuation than the aorta on the CT images were considered benign Covariates Type of PET‐CT scanner: integrated PET‐CT device (GE Discovery ST16) FDG dose: 3.7 to 4.44 MBq/kg Injection‐to‐scan time: 50 to 70 min Attenuation correction: yes Cut‐off values for test positivity (malignancy): Nodal positive FDG uptake was defined visually as a level greater than that of the surrounding mediastinum background
Target condition and reference standard(s)	Pathology from lung resection with mediastinal lymph node dissection
Flow and timing	All participants were accounted for in the results. All participants received the reference standard. There were no uninterpretable results
Comparative
Notes	The study was supported by the National Science and Technology Major Projects (2009ZX09501‐026), Doctoral Fund of Ministry of Education of China (20070023041) and Beijing Hope Run Special Fund (grant LC2007A02). Adverse events: None reported
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
		Unclear	High
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
Was there a pre‐specified cut‐off value?	No
Was a positive result defined?	Yes
		Low	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
		Low	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
		Low