Table 1.

Main features of the included RCTS

Study	Study design	Participants	Outcomes	Diagnostic method
Sajjad [4]	RCT, single center, 180 patients	All children between 5 and15 years of age of both genders admitted in the pediatric surgery emergency and having pediatric appendicitis score (PAS ≥ 7)	Primary outcome: Failure of NOM	PAS greater than or equal to 7
Perez Otereo [22]	RCT, single center, 39 patients	Patients between the ages of 6–17 years presenting with their first episode of uncomplicated acute appendicitis. Inclusion criteria for uncomplicated appendicitis consisted of < 48 h of symptoms, WBC < l8,000 µL, temperature < 103• Fahrenheit, appendix diameter < 11 mm, and radiographic absence of perforation or abscess on ultrasound and/or computed tomography (CT). Presence of an appendicolith did not exclude patients from eligibility	Primary outcomes: one–year success rate of antibiotics-alone and QOL measures assessed 1 month post discharge. Secondary outcome: length of stay and readmission rate	Abdominal US in 31 patients, while 5 patients were diagnosed solely by CT scan, and 3 were evaluated by both Imaging modalities when ultrasound was inconclusive
Svensson [21]	RCT, single center, 50 patients	All children between 5 and15 years of age of both genders admitted in the pediatric surgery emergency	Primary outcome: proportion of children in each group achieving •resolution of symptoms without significant complications”; Secondary outcomes: time from randomization to discharge, complications (wound infection, wound dehiscence, diarrhea, etc.), and recurrent appendicitis within 1 year of randomization	The diagnosis was made with the combination of clinical findings and imaging. All children underwent abdominal ultrasound scan, and a computed tomographic (CT) scan was performed when there was diagnostic: uncertainty

Study	Intervention	Surgical approach	Age OM	Age NOM	CRP OM (mg/L)	CRP NOM (mg/L)	Follow-up
Sajjad [4]	Intravenous meropenem (10 mg/kg/dose intravenous infusion 8 hourly) and metronidazole (20 mg/kg/day intravenous divided doses 8 hourly) for at least 48 h. Once the child started tolerating oral intake and clinically improved, the treatment was changed to oral ciprofloxacin (10 mg/kg/dose twice daily) and metronidazole (20 mg/"q./day two divided doses) for another 8 days	Not specified	10.11 ± 1.83	9.56 ± 1.82	7.79 ± 1.76	7.77 ± 1.8	1 Year
Perez Otero [22]	Intravenous piperacillin/tazobactam for 24–48 h followed by 10 days of oral ciprofloxacin and metronidazole	Laparoscopic	9.7 (7.3–14.4)	10.2 (8.5–11.1)	12.5 (5.0–41)	9.6 (3.3–22)	1 Year
Svensson [21]	Days 1–2: IV meropenem (10 mg/kg × 3 per 24 h) plus metronidazole {20 mg/kg × 1 per 24 h) Days 3–10: PO ciprofloxacin (20 mg/kg × 2 per 24 h) and metronidazole (20 mg/kg × 1 per 24 h)	Laparoscopic	11.1 (6.2–14.8)	12.2 (5.9–15.0)	27.0 (1.0–175.0)	30.5 (1.0–185.0)	1 Year