Five RCTs (980 participants) were included in the review. Sample sizes ranged from 40 to 369. Across studies, mean Jadad score was 1.8 out of 5 with scores ranging from 1 to 3. Three trials reported adequate randomisation procedures and one described loss to follow-up. Due to the nature of the treatments being compared, none of the studies was blinded. Follow-up ranged from seven months to one year.
Compared to appendectomy, participants who received antibiotics had significant reductions in complications (OR 0.54, 95% CI 0.37 to 0.78; five trials), duration of sick leave (SMD -0.19, 95% CI -0.33 to -0.06 unit of measurement not reported; three trials) and in the use of pain medication (SMD -1.55, 95% CI -1.96 to -1.14 unit of measurement not reported; two trials) . Appendectomy significantly reduced overall treatment failure compared to antibiotics treatment (OR 6.72, 95% CI 3.48 to 12.99; five trials). For complications and overall treatment failure, an Ι² value of 52% suggested the presence of moderate to substantial heterogeneity. There were no significant differences between antibiotic and appendectomy groups for initial treatment failure, length of stay, and duration of pain . The authors suggested evidence of publication bias for initial and overall treatment failure. The sensitivity analysis when one trial was removed did not alter the results.