Weltman 2000.

Study characteristics
Patient sampling	Consecutive patients aged 3 years or older suspected of having appendicitis underwent CT of the abdomen and pelvis. It is unclear whether all patients with suspected appendicitis were evaluated with CT. Exclusion criteria and recruitment period were not stated. No account of exclusions was given
Patient characteristics and setting	Age range: 3 to 73 years (mean age 34). The percentage of patients younger than 15 years of age is not stated. 46% women Radiology Department in East Meadows, New York, USA. Single‐centre study Disease spectrum: any suspicion of appendicitis
Index tests	Helical single‐slice CT of the abdomen and pelvis (XPress/SX, Toshiba). Contrast enhancement: 92% of participants had rectal contrast, 60% had IV contrast, and 2% had oral contrast. Slice thickness: 5 mm and 10 mm. Slice interval: 5 mm. Voltage and mAs product: not stated. Study authors compared the accuracy of CT with 5‐mm and 10‐mm slice thickness. Results for 5‐mm slice thickness are included in the meta‐analyses
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. Follow‐up for the 51 patients who did not have surgery consisted of outpatient visits for 30 patients 1 to 2 months after CT and telephone calls for 21 patients
Flow and timing	103 patients were enrolled and all had had CT. 3 patients were subsequently withdrawn because symptoms resolved after antibiotic treatment. Surgery was performed in 49 patients, 48 had appendicitis, and 51 patients received follow‐up
Comparative
Criteria for CT diagnosis of appendicitis	Confidence in the radiological diagnosis of appendicitis was graded from 1 to 3: 1: > 85% certainty ‐ abnormal appendix or appendicolith associated with periappendiceal inflammatory changes 2: 40% to 85% certainty ‐ right lower quadrant inflammatory changes, abscess, caecal wall thickening 3: < 40% certainty ‐ cannot rule out appendicitis due to equivocal, but potentially abnormal, findings Patients with grade 1 to 3 were considered CT‐positive in the accuracy analyses
Assessors of the CT‐scan	All CT‐scans were reevaluated for the study by 2 fellowship‐trained body imaging attending physicians with several years' experience in interpretation of CT‐scans for appendicitis
Notes	Study authors were contacted for additional data. No response was received
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?	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?	No
		Low	High
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	No
Were the reference standard results interpreted without knowledge of the results of the index tests?	No
		High	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