Hwangbo 2009.

Study characteristics
Patient sampling	Prospective consecutive patient series
Patient characteristics and setting	117 participants, median age = 66 (range = 41 to 84) years, 92 males/25 females, South Korea Histology of primary tumour Adenocarcinoma: N = 55; squamous cell: N = 53; large cell: N = 7; sarcomatoid carcinoma: N = 1; NSCLC NOS: N = 1; comorbidities: not reported Inclusion criteria Participants with histologically confirmed or strongly suspected potentially operable NSCLC from October 2006 to October 2007. Participants were required to have at least 1 mediastinal lymph node in an accessible location by EBUS‐TBNA, with a short diameter of 5 to 20 mm on chest CT scan axial image Exclusion criteria Participants with Pancoast tumours or unresectable tumours detected by white light bronchoscopy, medical inoperable participants, and participants not considered physically fit for surgery. Participants who had M1 disease, inoperable T4 disease, a bulky mediastinal lymph node (short diameter of 2 cm on chest CT scan axial image), or extra‐nodal invasion of the mediastinal lymph node visible on chest CT scan. When an abnormal supraclavicular lymph node was detected by chest CT scan or integrated PET‐CT scan in otherwise eligible participants, fine‐needle aspiration was performed, and participants who were found to have supraclavicular lymph node metastasis were excluded Previous/all tests Surgical tumour resectability was evaluated after staging workup for NSCLC, including either a CT scan of the chest and upper abdomen, integrated PET/CT scan, brain MRI, bone scan, or a combination of the aforementioned Clinical setting Center for Lung Cancer
Index tests	Participants fasted for 8 h and then received an I injection of FDG (10 to 15 mCi). Scanning was performed 60 min later PET/CT scan images were obtained by using either 1 of the following 2 combined PET‐CT scanners: a Biograph LSO (Siemens Medical Solutions; Hoffman Estates, IL, USA) or a Discovery LS (GE Medical Systems; Milwaukee, WI, USA). On each PET/CT scan, a spiral CT scan was performed and integrated with PET scan images. The data were analysed using dedicated workstations loaded with e.soft (Siemens Medical Solutions) and eNTEGRA™ (GE Medical Systems) software. The SUV was calculated as follows: SUV (decay‐corrected activity (in kilobecquerels) per ml of tissue volume)/injected‐FDG activity (in kilobecquerels)/body mass (in grams). The SUV was obtained by locating a region of interest on a lesion, and the maximum SUV within a region of interest was used. A maximum SUV > 2.5 on a lymph node was interpreted as positive Covariates Type of PET‐CT scanner: a Biograph LSO (Siemens Medical Solutions, Hoffman Estates, IL, USA) or a Discovery LS (GE Medical Systems; Milwaukee, WI, USA) FDG dose: 10 to 15 mCi Injection‐to‐scan time: 60 min Attenuation correction: yes Cut‐off values for test positivity (malignancy): maximum SUV > 2.5
Target condition and reference standard(s)	The reference standard consisted of EBUS‐TBNA for all 117 participants and surgical lymph node dissection in the 92 participants who were believed to be N2‐negative on the basis of EBUS‐TBNA. The results reported were based on the composite reference standard of both EBUS‐TBNA and surgical lymph node dissection
Flow and timing	12 of the originally 129 enrolled participants were excluded from the analyses: 2/12 participants had SCLC, 1/12 participants had organising pneumonia, 7/12 participants refused surgery, and 2/12 participants did not undergo lymph node dissection because of unexpected pleural metastasis found during surgery
Comparative
Notes	This work was supported by a National Cancer Center grant. The authors reported to the American College of Chest Physicians that no significant conflicts of interest exist with any companies/organisations whose products or services may be discussed in their article Adverse events: not reported
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	Low
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?	Yes
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?	Unclear
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	No
		Low