Lee 2012.

Study characteristics
Patient sampling	Retrospective consecutive? patient series
Patient characteristics and setting	160 participants, mean age = 60 (range = 29 to 80) years, 62 males/98 females, South Korea Histology of primary tumour Adenocarcinoma with bronchioloalveolar cell carcinoma: N = 55; adenocarcinoma with mixed type: N = 80; bronchioloalveolar cell carcinoma: N = 25; comorbidities: not reported Inclusion criteria Participants with pathologically confirmed T1 NSCLC between January 2005 and May 2011 who had available FDG PET‐CT and thin‐section chest CT (slice thickness ≤ 2.5 mm) before treatment, an interval ≤ 2 months between FDG PET‐CT, CT and treatment, NSCLC appearing as subsolid nodules on CT with lymph node staging, no previous chemotherapy/radiotherapy, and no previous/concurrent malignancy Exclusion criteria None listed Previous/all tests FDG‐PET/CT and CT. No further details reported Clinical setting Secondary/tertiary setting
Index tests	Before intravenous administration of FDG (5.2 MBq/kg body weight), all participants fasted for ≥ 6 hours. After administration, participants rested for 60 min before imaging. Thereafter, whole‐body PET images were acquired with the conventional protocol of FDG PET using a Gemini (Philips Medical Systems, Cleveland, OH, USA) equipped with a 2‐slice CT or Biograph 40 (Siemens Medical Solutions, Knoxville, TN, USA). 2 nuclear medicine physicians with 9 and 3 years PET/CT experience, respectively, evaluated all FDG PET‐CT images, and all decisions were reached in consensus. SUVmax of the primary lesions was also calculated. SUVmax threshold cut‐off of 3.5 was determined according to the previous experience of the authors' institute and other reports in a tuberculosis‐endemic area Covariates Type of PET‐CT scanner: Gemini (Philips Medical Systems, Cleveland, OH, USA) equipped with a 2‐slice CT or Biograph 40 (Siemens Medical Solutions, Knoxville, TN, USA) FDG dose: 5.2 MBq/kg Injection‐to‐scan time: 60 min Attenuation correction: not reported Cut‐off values for test positivity (malignancy): All lymph nodes in the thorax and extra‐thoracic regions with abnormal FDG uptake (SUVmax > 3.5) were considered positive, unless they showed high attenuation (> 70 HU) or benign calcification (central nodular, laminated, popcorn, or diffuse) on unenhanced CT images
Target condition and reference standard(s)	Pathological results from thoracotomy with (N = 128) or without (N = 32) mediastinoscopy. During thoracotomy, all visible and palpable lymph nodes accessible in the mediastinum were dissected. When preoperative imaging results suggested possible lymph node metastasis, they were also evaluated during mediastinoscopy or thoracotomy. Contralateral hilar lymph node metastasis was determined using clinical and imaging follow‐up studies
Flow and timing	All participants were accounted for in the results. All participants underwent surgical staging. There were no uninterpretable results
Comparative
Notes	From a tuberculosis‐endemic area The Research Grant of Korea Foundation for Cancer Research (grant number CB‐2011‐02‐01) and the Basic Science Research Program through the National Research Foundation of Korea, funded by the Ministry of Education, Science and Technology (grant number 2011‐0022379), supported the study 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?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	No
		Unclear	High
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
Was there a pre‐specified cut‐off value?	Yes
Was a positive result defined?	Yes
		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?	No
		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