Ozturk 2014.

Study characteristics
Patient sampling	Patients with suspected appendicitis were enrolled. Patients who had a definitive diagnosis and treatment without the use of CT were excluded. Otherwise no exclusion criteria were reported Recruitment period: July 2010 to November 2011
Patient characteristics and setting	Age range (median): 5 to 85 years (median age 33); 15% younger than 15 years. 42% women Hospital setting in Istanbul, Turkey. Single‐centre study Disease spectrum: intermediate suspicion of appendicitis
Index tests	Standard‐dose 64‐slice CT of the entire abdomen without contrast enhancement (Somatom Sensation, Siemens). Slice thickness, slice interval, voltage, and mAs product: not stated
Target condition and reference standard(s)	Appendicitis. Histological examination was performed in patients who had an appendectomy; follow‐up was provided for patients who did not have surgery. Follow‐up consisted of outpatient visits, the timing of which is unclear
Flow and timing	125 patients with suspected appendicitis who had CT were included. Of these patients, 93 had surgery, 83 had appendicitis confirmed histologically, and 32 were intended for outpatient follow‐up. It is unclear whether all 32 patients received follow‐up. All 125 patients were included in the analyses
Comparative
Criteria for CT diagnosis of appendicitis	Appendix diameter > 8 mm, appendicolith, periappendicular fluid collection, increased appendix wall thickness, appearance of inflammation in the mesoappendix
Assessors of the CT‐scan	Radiologist on duty. Management of patients was planned according to results of the CT
Notes	The corresponding author provided information about the CT‐scanner, the CT‐protocol, and the numbers of true‐positives, false‐positives, false‐negatives, and true‐negatives
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?	Unclear
Does the study population represent an unselected sample of adults with suspected appendicitis?	No
		High	High
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?	Unclear
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