Table 2

Author, date, and countryPatient groupStudy type (level of evidence)OutcomesKey resultsStudy weaknesses
Doraiswamy NV, 1979, UK375 children admitted with clinical diagnosis of acute appendicitisDiagnostic test studyWCC>15000 (0–10 years) or WCC>10000 (10–15 years)Sens 42%; Spec 97%; LR+ 12.5; LR− 0.60Unclear if blinded No gold standard No follow up of non-operative cases
225 found to have acute appendicitis, 50 with a normal appendix, and 100 in whom symptoms resolved spontaneously
Miskowiak J and Burcharth F, 1982, Denmark238 patients admitted with suspected acute appendicitisDiagnostic test study, blindedWCC>15000.Sens 19%; Spec 85%; LR+ 1.26; LR− 0.95No gold standard
74 were below 15 years
Peltola H et al, 1986, Sweden162 children (1.9–15.6) admitted with suspected acute appendicitisDiagnostic test studyWCC>15000. HistologySens 60%; Spec 84%; LR+ 3.75; LR− 0.48Unclear if blinded No gold standard No follow up of non-operative cases
Lau WY et al, 1989, Australia1389 patients (1–87), with right lower abdominal pain, consistent with appendicitisDiagnostic test study, blindedWCC>15000 (group 1–10). WCC>13000 (group 10–15). HistologySens 60.5%; Spec 100%; LR+ INF; LR− 0.35No gold standard Not analysed by age specific WCC Raw data not available for analysis by age group
177 children (1–15)
Non-operative group followed up at 2 and 6 weeks