Kendall 2009.

Study characteristics
Patient sampling	Prospective cohort study
Patient characteristics and setting	Study location: USA Study period: July 1998 to June 1999 Care setting: level I trauma centre Mass casualty: no Participants enrolled: 164 Participants included in analysis: 152: 95 men and 57 women Age: mean age 34 (range 6 to 91 years) Type of injury: blunt abdominal trauma Injury severity: not reported Haemodynamic stability: not reported Inclusion criteria: a convenience sample of patients who presented to the emergency department following blunt abdominal trauma and who subsequently received CT scans of the chest or abdomen during their evaluations Exclusion criteria: transferred from another facility with known solid organ injury; if the CT was interrupted or not completed; if performing the secondary US would delay necessary patient care; or if the trauma was not a blunt mechanism
Index tests	Index test: FAST US protocol: US examinations were performed by emergency medicine residents or attending physicians experienced in the use of US for detecting haemoperitoneum. Ultrasonographers determined the presence or absence of liver or spleen injury prospectively. The specific purpose of the secondary US was to evaluate the liver and splenic parenchyma for solid organ injury. The secondary US consisted of long‐ and short‐axis scans through both organs. Hardware used: Toshiba SSH‐140A (Toshiba, San Francisco, CA) with a 3.75‐MHz phased array transducer Description of imaging technique: a 4‐view US examination to detect haemoperitoneum or pericardial effusion
Target condition and reference standard(s)	Target condition: free fluid and air Reference standard: CT (technique specification not reported) Description of technique: the criterion diagnostic standard was made using CT. All CT interpretations were performed by attending radiologists who were blinded to the results of the secondary US examination.
Flow and timing	Time between US and reference standard: not reported
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
		Unclear	Low
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
If a threshold was used, was it pre‐specified?	Yes
Was the qualification of the US operator appropriate?	No
Was the US hardware (i.e. generation, manufacturer, probe, etc.) up to date?	Yes
Was the US protocol (i.e. 'classic' FAST) appropriate?	Yes
Are there concerns that the definition or performance of the index test (i.e. POC US of trauma) do not match generally accepted, established, or practiced rules or recommendations?	No
		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?	Yes
Was the qualification of the doctors (i.e. radiologists, surgeons, etc.) determining the reference standard appropriate?	Yes
Was the reference imaging standard (i.e. MDCT‐rows (4 to ≥ 256 slices), contrast‐imaging, etc.) up to date?	Unclear
Are there concerns that the definition or performance of the reference tests (e.g. CT, MRI, laparatomy, thoracotomy, autopsy, etc.) do not match generally accepted, established, or practiced rules or recommendations?	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
Did all participants receive a reference standard? (Risk of partial verification bias)	Yes
		Low