Matthay 1986

Methods	An USA prospective randomised trial
Participants	Number of participants: 88 Number randomised: Experimental group (BCG‐treated + surgery): 48 Control group (Control subjects + surgery): 40 Number evaluated: Experimental group: 48, age (Mean ± SD): 61 ± 9 years Control group: 37, age (Mean ± SD): 61 ± 10 years Diagnosis: Patients with potentially resectable non‐small cell carcinoma of the lung Inclusion: Patients suspected of having lung cancer were excluded if a definite diagnosis had not been established before thoracotomy.
Interventions	Experimental group : Injecting BCG 10⁷ viable organisms for PPD skin test‐negative participants and 5x10⁶ for PPD‐positive participants into the tumour mass. Then underwent thoracotomy 2 to 3 weeks after intratumoural injection of BCG. Control group: All control participants underwent thoracotomy immediately following randomisation. A 12‐week course of 300 mg INH daily was given to all participants.
Outcomes	Duration of follow‐up (median ± SD): experimental group: 986 ± 412 days; control group: 1062 ± 390 days OS, Median time to recurrence
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Stratified block randomisation method."Patients were divided into 2 groups according to a table of random numbers and sealed‐envelope technique in strict numerical order of entry"
Allocation concealment (selection bias)	Low risk	"Patients were divided into 2 groups according to a table of random numbers and sealed‐envelope technique in strict numerical order of entry"
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label design
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not described
Incomplete outcome data (attrition bias) All outcomes	Low risk	85 randomised participants were included in analysis (96.6%)
Selective reporting (reporting bias)	High risk	No prior protocol was available, and no pre‐specified primary outcome was reported.
Other bias	Low risk	No obvious potential source of bias