Blaivas 2005.

Study characteristics
Patient Sampling	Location: Augusta, GA, USA Period of data collection: September 2003 to May 2004 Sampling technique: Convenience sampling based on researcher availability
Patient characteristics and setting	Sample size: 176 patients Mean age: not reported Male gender: 57% Blunt trauma: 100% Penetrating trauma: 0% Inclusion criteria: blunt trauma ED patients >17yo with FAST, CXR, and CT or TT Exclusion criteria: any exam unable to be completed.
Index tests	CUS Operator: emergency physicians Probe: 4 to 2 MHz microconvex curvilinear probe Positivity definition: absence of lung slide in 4 locations of each hemithorax CXR in supine position interpreted by trauma surgeon.
Target condition and reference standard(s)	Reference standard: CT of the chest interpreted by blinded radiologists or rush of air or bubbling in chest drain after tube thoracostomy Target condition: traumatic pneumothorax
Flow and timing	Time to CUS: unclear Time to CXR: unclear Patients lost‐to‐follow‐up or excluded: all enrolled patients were included in the analysis
Comparative
Notes
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	No
Did the study avoid inappropriate exclusions?	Yes
Could the selection of patients have introduced bias?		High risk
Are there concerns that the included patients and setting do not match the review question?			Low concern
DOMAIN 2: Index Test (CUS)
Were index test results interpreted without knowledge of the results of CT or TT?	Yes
Were index test results interpreted without knowledge of the results of the other index test?	Yes
Did the authors prespecify the criteria for a positive CUS finding?	Yes
Could the conduct or interpretation of the index test have introduced bias?		Low risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
DOMAIN 2: Index Test (CXR)
Were index test results interpreted without knowledge of the results of CT or TT?	Yes
Were index test results interpreted without knowledge of the results of the other index test?	Yes
Did the authors prespecify the criteria for a positive CUS finding?
Could the conduct or interpretation of the index test have introduced bias?		Low risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
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 CUS?	Yes
Were the reference standard results interpreted without knowledge of the results of CXR?	Yes
Could the reference standard, its conduct, or its interpretation have introduced bias?		Low risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Low concern
DOMAIN 4: Flow and Timing
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
Was there an appropriate interval between CUS, CXR, and CT/TT?	Unclear
Could the patient flow have introduced bias?		Unclear risk