Stacher 1999.
Study characteristics | |||
Patient sampling | Adult patients (> 18 years) presented with suspected appendicitis between December 1997 and December 1998. It is unclear whether all patients who had an appendectomy during the study period also had a CT‐scan. Pregnant and breastfeeding women were excluded | ||
Patient characteristics and setting | Mean age: 42 years. 41% women. Pregnant or nursing women and patients younger than 18 years were excluded Clinical setting unclear. Austria. Single‐centre study Disease spectrum: unclear |
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Index tests | Unenhanced helical CT of the lower abdomen (Somatom Plus 4, Siemens). Slice thickness: 5 mm. Slice interval: 4 mm. Voltage: 140 kV. mAs product: 92.5 mAs. Multi‐planar reconstructions were used if axial images were insufficient for definitive diagnosis | ||
Target condition and reference standard(s) | Appendicitis. Of the 56 included patients, 32 had surgery with histological assessment of the removed appendix, and 24 had follow‐up. Follow‐up was performed after 2 months, but otherwise the concept of follow‐up is not stated | ||
Flow and timing | 56 patients were included and analysed | ||
Comparative | |||
Criteria for CT diagnosis of appendicitis | Positive CT findings were defined as a combination of the following features: appendix diameter > 6 mm; and periappendiceal fat stranding | ||
Assessors of the CT‐scan | 3 experienced radiologists. Non‐paired assessments were performed, but consensus assessments were used if 1 radiologist was in doubt about the diagnosis | ||
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 | ||
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? | Yes | ||
Was the analysis based on the initial evaluation of the CT‐scan by the radiologist on call? | Yes | ||
Low | Low | ||
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? | Unclear | ||
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? | Yes | ||
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 |