Search strategy. The Cochrane Library, Embase, MEDLINE and Chinese Biomedical Literature databases were searched to identify all RCTs comparing IEP to the EP regimen in patients with histologically proven SCLC. The following keywords were used: ‘small‑cell lung cancer’ or ‘small‑cell lung carcinoma’, ‘etoposide’ and ‘ifosfamide’. The search was limited to ‘randomized controlled trials’. No limits based on language