Lad 1994a.

Methods	Parallel randomised trial
Participants	Adults with SCLC diagnosed on bronchial biopsy, with no radiologic evidence of extrathoracic metastases, and appropriate for operation/radiotherapy
Interventions	All participants had induction chemotherapy for 5 cycles prior to randomisation (cyclophosphamide, 1 g/m²; doxorubicin, 50 mg/m²; and vincristine, 1.4 mg/m², every 3 weeks for five cycles). Surgery ‐ 70 participants. Complete resection in 77% of surgical participants, with 6% resulting in incomplete resection (positive margins), and 17% considered unresectable at time of thoracotomy. Compared to no intervention ‐ 76 participants. Following, all had chest and brain irradiation. (The radiation therapy doses were 50 Gy in 25 fractions to the chest, the target being the initial (pre‐chemotherapy) tumour volume and mediastinum, and 30 Gy in 15 fractions whole‐brain prophylaxis. Brain and chest irradiation were delivered concurrently).
Outcomes	Median survival, loco‐regional progression. Adverse events, including treatment related deaths, were not reported.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Study was reported as randomised, but no details for methods were given.
Allocation concealment (selection bias)	Unclear risk	No details for allocation concealment were given.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	It is likely that participants were aware of the intervention they were assigned to. It is likely the treating physicians were aware of the intervention received and this may have affected the choice of co‐interventions. Lack of blinding is unlikely to have affected the results in the main outcome of survival but may have an effect on the measurement of other outcomes.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	It was not clear whether outcome assessors were truly blinded to the intervention. Lack of blinding is unlikely to have affected the results in the main outcome of survival, but it is unclear how it may have affected other outcomes.
Incomplete outcome data (attrition bias) All outcomes	Low risk	All participants were accounted for.
Selective reporting (reporting bias)	Low risk	The study fully reported all prespecified outcomes.
Other bias	Unclear risk	It was not clear if any participants crossed over to other intervention arms.