Table 1. Design and characteristic of trials included in our meta-analysis.

Source	No. of patients	Stage of disease	Induction chemotherapy	Maintenance chemotherapy	Jadad score
Byrne MJ (1989) [6]	66	Limited disease	Cisplatinum and VP16213 q for 3 weeks followed by cyclophosphamide, vincristine and methotrexate (CVM)q. 4 weeks.	Cyclophosphamide, vincristine and methotrexate for additional 6 cycles; no treatment	3
Bleehen NM (1989) [7]	265	Limited disease and extensive disease	Etoposide, cyclophosphamide, methotrexate and vincristine for 6 cycles	Etoposide, cyclophosphamide, methotrexate and vincristine for 6 cycles; no treatment	1
DS Ettinger (1990) [8]	36	Extensive disease	Cyclophosphamide, doxorubicin, vincristine-altretamine for 6–8 cycles	Cyclophosphamide, doxorubicin, vincristine -altretamine up to 28 cycles; no treatment	3
DS Ettinger (1990) [8]	50	Extensive disease	Cyclophosphamide, doxorubicin, vincristine-altretamine (hexamethylmelamine), etoposide, and methotrexate for 6–8 cycles	Cyclophosphamide, doxorubicin, vincristine -altretamine (hexamethylmelamine), etoposide, and methotrexate up to cycles; no treatment	3
G Giaccone (1993) [10]	434	Limited disease and extensive disease	Cyclophosphamide, doxorubicin, and etoposide for 5 cycles	cyclophosphamide, doxorubicin, and etoposide for additional 7 cycles; no treatment	3
JP Sculier (1996) [11]	91	Limited disease and extensive disease	Ifosfamide, etoposide, and an anthracycline (doxorubicin or epirubicin) for 6 cycles	Etoposide and vindesine for additional 12 cycles; no treatment	3
JH Schiller (2001) [12]	223	Extensive disease	Cisplatin and etoposide for 4 cycles	Topotecan for additional 4 cycles; no treatment	3
DH Johnson (1993) [13]	151	Limited disease	Cyclophosphamide, doxorubicin, and vincristine for 6 cycles, plus radiotherapy	cisplatin plus etoposide for 2 cycles; no treatment	2
Midlands Small Cell Lung Cancer Group (1986) [24]	61	Extensive disease	Vincristine, doxorubicin, and cyclophosphamide for 6 cycles	Vincristine, doxorubicin, and cyclophosphamide for additional 8 cycles; no treatment	2
Midlands Small Cell Lung Cancer Group (1986) [24]	32	Limited disease	Vincristine, doxorubicin, and cyclophosphamide for 6 cycles	Vincristine, doxorubicin, and cyclophosphamide for additional 8 cycles; no treatment	2
Han JY (2008) [25]	45	Extensive disease	Irinotecan plus cisplatin for 8 cycles	Irinotecan plus cisplatin for additional 6 cycles; no treatment	3
NH Hanna (2002) [26]	144	Extensive disease	Etoposide, ifosfamide and cisplatin for 4 cycles	Etoposide for additional 3 cycles; no treatment	1
JM Beith (1996) [27]	129	Limited disease and extensive disease	Cisplatin and etoposide (EP) for 4 cycles, plus cranial and local radiotherapy.	Vincristine, doxorubicin and cyclophosphamide for 10 cycles; no treatment	2
The “Petites Cellules” Group (1992) [28]	79	Limited disease and extensive disease	lomustine, cyclophosphamide, doxorubicin and etoposide for 6 cycles	cyclophosphamide, doxorubicin and etoposide for additional 6 cycles; no treatment	1