Karabulut 2014.

Study characteristics
Patient sampling	Patients with suspected appendicitis were included. No exclusion criteria were reported Recruitment period: December 2005 to December 2008
Patient characteristics and setting	Age range (mean): 6 to 77 years (27) ‐ proportion younger than 15 years not reported (study authors contacted ‐ no response). 52% women. Exclusion criteria not reported Disease spectrum and clinical setting: not stated. Single‐centre study
Index tests	Two helical CT‐scanners were used: Brillance 16 (Philips Medical Systems): 16‐slice. Slice thickness: 3 mm. Slice interval: 1.5 mm. Voltage: 120 kV. mAs product: 50 mAs. Unenhanced. Lower abdomen MW8000 (Philips Medical Systems): 2‐slice. Slice thickness: 3.2 mm. Slice interval: 1.6 mm. Voltage: 120 kV. mAs product: 50 mAs. Unenhanced. Lower abdomen
Target condition and reference standard(s)	Appendicitis. Histological examination in patients who had an appendectomy. Otherwise alternative intraoperative findings. Follow‐up in patients who did not have surgery ‐ review of medical charts and/or a telephone call after 21 to 31 days
Flow and timing	104 patients were recruited. All had CT of the lower abdomen, 40 had surgery, and 39 had appendicitis confirmed histologically. 64 patients were followed up
Comparative
Criteria for CT diagnosis of appendicitis	Enlarged outer appendix diameter (threshold not stated), thickened appendix wall, appendicolith, periappendicular fat stranding, pericaecal or periappendicular fluid or abscess. Enlarged appendix diameter was not accepted as a single criterion unless it was accompanied by intraluminal, mural, or periappendicular soft tissue changes
Assessors of the CT‐scan	1 senior radiologist
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?	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?	Unclear
If a threshold was used, was it pre‐specified?	Yes
Is the index test described in sufficient detail to permit its replication?	Yes
Was the analysis based on the initial evaluation of the CT‐scan by the radiologist on call?	Unclear
		Unclear	Unclear
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
		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