Peter 2009.

Methods	Parellel randomised controlled trial Randomisation ratio: 1:1 Superiority design Number of study centres: 1 Country: USA
Participants	N recruited = 36 N randomised = 36 N reported outcomes = 36 Mean age = 5 years Gender = not reported N tPA = 18 N VATS = 18 Inclusion criteria: Only patients under 18 years of age were included. Diagnosis of empyema: septations or loculations in pleural space on CT or ultrasound; or purulent tap with WCC > 10,000 cells/uL Exclusion criteria: Contraindication to either fibrinolytic agent or thoracoscopy Additional foci of infection Immunosuppression Comorbid conditions that would extend hospital stay beyond course of empyema
Interventions	Titration period and treatment: VATS: Performed by 1 of 5 staff surgeons. Chest drain left in place post procedure. tPA: 12Fr chest tube inserted and drained with suction. Fibrinolysis was performed by mixing 4 mg of tPA into 40 mL of sterile normal saline. Tube clamped for 1 hr before continuing suction. This was done once on tube insertion and 2 additional doses each at 24 hrs. Common: Clindamycin (10 mg/kg/dose) every 6 hours and ceftriaxone (25 mg/kg per dose) every 12 hours. If haemodynamic instability existed (hypotension, need for vasoactive medications, or persistent tachycardia), then vancomycin (15 mg/kg per dose) every 6 hours was added. Antibiotic therapy was tailored toward positive culture results and the individual patient’s course. Tubes removed when no air leakage and drainage output was < 1 mL/kg per day calculated for the previous 12 hours.
Outcomes	At diagnosis, there were no differences between groups in age, weight, degree of oxygen support, white blood cell count, or days of symptoms. No difference in LOS after intervention, days of oxygen requirement, days until afebrile, or analgesic requirements VATS higher cost. 3 in tPA group required VATS. 1 in VATS group required ventilator, 1 required ventilator and temporary dialysis Primary outcome(s): LOS: tPA (6.8) versus VATS (6.9) Post‐therapy days with oxygen requirement: tPA (2.3) versus VATS (2.3) Afebrile days after intervention: tPA (3.8) versus VATS (3.1) Analgesia: tPA (21.4) versus VATS (22.3) Hospital charges: tPA (USD 7600) versus VATS (USD 11,700); P < 0.05
Notes	Language of publication: English Publication status: peer‐reviewed journal Stated aim for study: "we conducted a prospective, randomised trial comparing VATS to fibrinolytic therapy in children with empyema." Funding: not disclosed Conflicts of interest: not disclosed
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"Computer generated using an individual unit of randomization in an unstratified sequence in blocks of 4"
Allocation concealment (selection bias)	Low risk	"The randomization sequence was accessed to identify the next allotment after the consent form was signed"
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Blinding not possible.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Low risk	There were no missing outcome data.
Selective reporting (reporting bias)	Low risk	No protocol. However, all outcomes in methods were included in results.
Other bias	Unclear risk	Funding source not reported.