Funaki 1998.

Study characteristics
Patient sampling	Patients presenting to an Emergency Department with equivocal symptoms and signs of appendicitis were referred for CT examination. Unequivocal cases of appendicitis underwent immediate laparotomy. Entrance criteria were based on the clinical judgement of the Emergency Department physician. No exclusion criteria were stated Recruitment period: May 1997 to January 1998
Patient characteristics and setting	Age range (mean): 6 to 71 years (ns). 63% women Radiology Department in Hilo, Hawaii, USA. Single‐centre study Disease spectrum: intermediate suspicion of appendicitis
Index tests	Single‐slice helical CT of the lower abdomen with oral (in 95%) and rectal (in 100%) contrast material (PQ 5000, Picker International). Slice thickness: 5 mm. Slice interval: 2.5 mm. Voltage and mAs product: not stated
Target condition and reference standard(s)	Appendicitis. Surgical and histopathological findings were reported for patients who had surgery with or without appendectomy. Patients who did not have surgery were followed up clinically for at least 2 months. No further description of follow‐up was provided
Flow and timing	100 patients were included. It is unclear whether some were excluded from participation. 45 patients had surgery; 30 had appendicitis. Patients who did not have surgery were followed up clinically and were free of symptoms for at least 2 months after CT examination
Comparative
Criteria for CT diagnosis of appendicitis	A non‐opacified and enlarged (> 6 mm in diameter) appendix was noted. Ancillary signs of appendicitis, including right lower quadrant inflammation, appendicoliths. lymphadenopathy, and caecal apical changes (caecal bar or arrowhead sign), were also recorded. Findings were interpreted as negative if the appendix was visualised with intraluminal air or contrast material extending to its tip
Assessors of the CT‐scan	11 board certified general radiologists
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?	Unclear
Does the study population represent an unselected sample of adults with suspected appendicitis?	Unclear
		Unclear	Unclear
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
Is the index test described in sufficient detail to permit its replication?	No
Was the analysis based on the initial evaluation of the CT‐scan by the radiologist on call?	Yes
		Low	High
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
		Unclear	Low
DOMAIN 4: Flow and Timing
Did all patients receive a reference standard?	Yes
Did all patients receive the same reference standard?	No
Did all patients with a positive CT‐scan have surgery?	No
Did all patients with a negative CT‐scan have clinical follow‐up?	No
Was the choice of reference standard independent of the result of the index test?	No
Were all patients included in the analyses?	Yes
		High