Hekimoglu 2011.
Study characteristics | |||
Patient sampling | Patients presented with acute, non‐traumatic abdominal pain clinically suspected to be secondary to acute appendicitis. Patients with possible contrast allergy, pregnant women, and patients with abdominal trauma were excluded Recruitment period: March 2008 to October 2010 Patients were randomly allocated to receive either CT with intravenous contrast enhancement or CT with intravenous and oral contrast enhancement |
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Patient characteristics and setting | Intravenous contrast group: age range (mean): 20 to 66 years (42); 38% women Intravenous and oral contrast group: age range (mean): 18 to 74 years (38); 42% women Pregnant women and patients with possible contrast allergy were excluded Emergency Department in Ankara, Turkey. Single‐centre study Disease spectrum: unclear |
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Index tests | 16‐slice CT of the entire abdomen with intravenous contrast enhancement (Sensation 16, Siemens Medical Solutions). Multi‐planar reconstructions were used Slice thickness: 5 mm. Slice interval: not stated. Voltage: 120 kV. mAs product: not stated Patients were randomly allocated to receive either CT with intravenous contrast enhancement or CT with intravenous and oral contrast enhancement |
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Target condition and reference standard(s) | Appendicitis. Histological examination was performed in patients who had an appendectomy and follow‐up was provided for patients who did not have surgery (review of medical records and telephone interviews 1 day and 1 week after discharge) | ||
Flow and timing | Intravenous contrast group: 100 patients were included. All had CT; 26 had appendicitis confirmed histologically Intravenous and oral contrast group: 100 patients were included. All had CT; 32 had appendicitis confirmed histologically The number who had surgery and the number receiving follow‐up are not reported for any of the groups | ||
Comparative | |||
Criteria for CT diagnosis of appendicitis | Appendix diameter > 6 mm, thickened appendix wall, appendix wall hyperenhancement, periappendiceal fat stranding. In patients who had oral contrast enhancement, the absence of contrast filling of the appendix was considered an additional criterion in favour of appendicitis Radiologists used a 5‐point Likert scale to rate their confidence in the radiological diagnosis of appendicitis (1: definitely absent, 2: probably absent, 3: intermediate, 4: probably present, 5: definitely present) Patients rated 1 or 2 were considered CT negative; patients rated 4 or 5 were considered CT‐positive. Patients rated 3 were counted as CT negative when appendicitis was confirmed, and as CT‐positive when appendicitis was not confirmed (worst‐case scenario) |
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Assessors of the CT‐scan | All CT‐scans were evaluated by 2 radiologists with over 5 years' experience in interpreting abdominal CT‐scans Sensitivity and specificity were reported for each of the 2 radiologists. No consensus evaluation is available. Rounded mean numbers of true‐positives, false‐positives, false‐negatives, and true negatives were used in meta‐analyses |
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Notes | Patients were recruited for a randomised trial comparing CT with intravenous contrast enhancement vs CT with oral and intravenous contrast enhancement. The 2 groups are considered as individual studies in the meta‐analyses | ||
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? | Yes | ||
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? | Yes | ||
Was the analysis based on the initial evaluation of the CT‐scan by the radiologist on call? | Unclear | ||
Low | 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? | Unclear | ||
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 |