El‐Hariri 2012.

Study characteristics
Patient sampling	Prospective/retrospective? consecutive? patient series
Patient characteristics and setting	33 participants, median age = 64 (range = 34 to 76) years, 28 males/5 females, Egypt Histology of primary tumour Not reported; comorbidities: not reported Inclusion criteria Participants with lung cancer who underwent whole body‐integrated PET‐CT imaging for staging lung lesions in the period from September 2010 till December 2011 Exclusion criteria Not reported Previous/all reported tests Not reported Clinical setting Departments of Radiology Diagnosis and Cardio‐thoracic Surgery The inclusion of only participants who received surgery 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 already on PET‐CT
Index tests	Combined PET‐CT imaging was conducted by using the Siemens medical solution system (Siemens Biograph 64 PET‐CT scanner). To ensure diagnostic CT image quality, 120 ml of iodinated contrast agent was administered intravenously using an automated injector. CT was performed during breath‐hold at expiration tidal volume. This limited breath‐hold technique was used to avoid respiration artifacts on the CT images and for a good match between the CT and the PET images. PET imaging was performed 60 min after the administration of 300 MBq (about 8 mci) of FDG by multiple overlapping bed positions (5 min per bed position). Attenuation correction was based on the CT data. Participants had been instructed to fast for 6 h prior to starting the examination. Blood samples collected before the injection of the radioactive tracer ensured blood glucose levels in the normal range Covariates Type of PET‐CT scanner: Biograph 64 (Siemens Medical Solutions) FDG dose: 300 MBq Injection‐to‐scan time: 60 min Attenuation correction: yes Cut‐off values for test positivity (malignancy): Lymph nodes with a short axis diameter greater than 10 mm on CT were considered positive. PET images were assessed qualitatively for regions of focally increased FDG uptake, as well as quantitatively by determining standardised uptake values. An increase in FDG uptake to a level greater than that in the surrounding tissue at qualitative analysis and a standard uptake value of more than 2.5 were considered to characterise malignancy. Lymph nodes with increased FDG uptake were considered positive for metastatic spread even when they were smaller than 1 cm in short axis diameter. PET‐negative lymph nodes were considered as benign, even when they were larger than 1 cm in short axis diameter. Mediastinal hotspots on PET but without a visible lesion on CT were considered as negative on integrated PET/CT
Target condition and reference standard(s)	Tumour resection and mediastinal lymph node dissection were performed in 22 participants. Surgery was performed within a maximum of 10 days after imaging. The surgeon sampled all visible and palpable lymph nodes that were accessible in the hilum and mediastinum. The remaining 11 participants underwent mediastinoscopy for lymph node staging
Flow and timing	All the participants were accounted for
Comparative
Notes	Funding: no details reported 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?	Unclear
		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?	Unclear
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?	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