Rao 1997.
Study characteristics | |||
Patient sampling | Consecutive patients with suspected appendicitis were referred for CT examination of the appendix. Patients were referred from the Emergency Department or from private surgeons' offices. It is unclear whether all patients with clinically suspected appendicitis had CT. Pregnant women and patients younger than 6 years were excluded. Women with gynaecological abnormalities detected by pelvic ultrasonography were ineligible for the study Recruitment period: October 1995 to March 1996 |
||
Patient characteristics and setting | Age range: 6 to 84 years. The proportion of patients younger than 15 years is not reported. 54% women Department of Radiology, Boston, Massachusetts, USA. Single‐centre study Disease spectrum: unclear | ||
Index tests | Single‐slice helical CT of the lower abdomen with oral and rectal contrast enhancement (HiSpeed Advantage, General Electric). Slice thickness and slice interval: 5 mm. Voltage and mAs product: not stated. 4 patients with a potential contraindication to rectal contrast received only oral contrast enhancement | ||
Target condition and reference standard(s) | Appendicitis. Intraoperative findings or histological examination in patients who had surgery with or without appendectomy. Follow‐up in patients who did not have surgery. Follow‐up consisted of at least 1 outpatient clinic visit and phone calls approximately 1 week, 1 month, and 3 months after the CT‐scan | ||
Flow and timing | 103 patients were referred for CT examination. 2 patients declined to participate. Of the 101 included patients, 61 had surgery and 56 had appendicitis. Clinical follow‐up was uneventful in 38 patients. 1 patient was lost to follow‐up, and the final diagnosis was unclear in another. Both of these patients were excluded from the analyses, which included 99 patients | ||
Comparative | |||
Criteria for CT diagnosis of appendicitis | Appendix diameter > 6 mm with periappendiceal inflammatory changes such as fat stranding, fluid collection, phlegmon, or extraluminal gas | ||
Assessors of the CT‐scan | 1 board certified 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? | Yes | ||
Does the study population represent an unselected sample of adults with suspected appendicitis? | No | ||
Unclear | 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? | 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 |