Tso 1992.

Study characteristics
Patient sampling	Prospective study
Patient characteristics and setting	Study location: USA Study period: 8 consecutive months in the 1990 academic year Care setting: level I trauma centre Mass casualty: no Participants enrolled: 163: gender ratio male:female 3:1 Participants included in analysis: 163 Age: mean age 34 years (range 2 to 93 years) Type of injury: blunt abdominal trauma Injury severity: ISS 13, GCS 14 Haemodynamic stability: stable conditions Inclusion criteria: patients admitted to trauma centre through the admitting area and judged to require DPL or CT for evaluation of intra‐abdominal injury Exclusion criteria: hypotension, suspected severe head injury, indications for immediate laparotomy, and the discretion of the attending traumatologist
Index tests	Index test: FAST US protocol: participants evaluated by real‐time sector scanning sonography, within 1 hour of admission, by surgical trauma fellows Hardware used: Siemens Sonoline SL‐2 using either 3‐ or 5‐MHz transducers Description of imaging technique: the pelvis, the paracolic gutters, and the subhepatic space were studied for evidence of free intraperitoneal fluid. Positive sonography studies showed free peritoneal or extraperitoneal fluid or organ disruption.
Target condition and reference standard(s)	Target condition: free fluid and air, organ injury Reference standard: CT (technique specification not reported), DPL, laparotomy Description of technique: positive CT scans showed free peritoneal or extraperitoneal fluid or organ disruption
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?	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
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
		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
Was the qualification of the doctors (i.e. radiologists, surgeons, etc.) determining the reference standard appropriate?	Unclear
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?	Yes
		Unclear	High
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?	No
Were all patients included in the analysis?	Yes
Did all participants receive a reference standard? (Risk of partial verification bias)	Yes
		Low