Dolich 2001.

Study characteristics
Patient sampling	Retrospective study
Patient characteristics and setting	Study location: USA Study period: 30‐month period ending July 1997 Care setting: level I trauma centre Mass casualty: no Participants enrolled: 2576: 1880 men and 696 women Participants included in analysis: 616 Age: mean age 38 years (range 1 to 94 years) Type of injury: blunt abdominal trauma Injury severity: GCS ≤ 12 Haemodynamic stability: stable and unstable condition Inclusion criteria: all patients had abdominal US in the evaluation of blunt abdominal trauma and were entered into a trauma US database. This database was analysed to determine the utility of US in the evaluation of blunt abdominal trauma. Exclusion criteria: not reported
Index tests	Index test: US US protocol: real‐time US images were interpreted by an attending radiologist or senior radiology resident in conjunction with the trauma surgery attending or fellow, or both. The evidence of free intraperitoneal fluid or parenchymal injury was considered a positive result. US was considered negative if the above were absent on a technically satisfactory examination. US examinations were deemed to be indeterminate if they revealed questionable free fluid or solid organ injury, or were technically limited. Hardware used: Accuson 128X P/10 (Mountain View, CA) with a 3.5‐MHz sector transducer Description of imaging technique: with the participant in the supine position, views of the pericardium, bilateral subphrenic spaces, Morison’s pouch, perisplenic region, and pelvis were examined for the presence of free intraperitoneal fluid or solid organ injury
Target condition and reference standard(s)	Target condition: free fluid, solid organ injury Reference standard: CT (technical specifications not reported), exploratory laparotomy (DPL, observation) Description of technique: in general, unstable participants with a positive US were taken to the operating room for exploratory laparotomy. Participants with a positive US who remained haemodynamically stable during the initial assessment in the resuscitation area underwent abdominal CT scan to evaluate further the extent and nature of intra‐abdominal injury. For statistical analysis, a true‐positive result was defined as a positive US with confirmation of injury by CT scan, DPL, or exploratory laparotomy. A negative US with confirmation by observation, CT scan, DPL, or laparotomy was deemed a true negative. A false‐positive result was defined as a positive US with subsequent absence of intra‐abdominal injury by CT scan, DPL, or laparotomy. A false‐negative result was defined as a negative US in a participant with intra‐abdominal injury, as documented by CT scan, DPL, or exploratory laparotomy.
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?	Unclear
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?	Yes
Was the US hardware (i.e. generation, manufacturer, probe, etc.) up to date?	Yes
Was the US protocol (i.e. 'classic' FAST) appropriate?	No
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?	Unclear
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