. 2017 Apr 21;2017(4):CD011917. doi: 10.1002/14651858.CD011917.pub2

for the main comparison.

Surgery compared with no surgery for limited‐stage small‐cell lung cancer
Patient or population: People with limited‐stage small‐cell lung cancer Settings: ambulatory care Intervention: surgery Comparison: no surgery
Outcomes	Impact	No of Participants  (studies)	Quality of the evidence  (GRADE)
Survival	Survival is difficult to interpret in these studies^a	3 studies (330 participants)^b	⊕⊖⊖⊖ very low^c
Treatment related mortality	Treatment‐related mortality is difficult to interpret in these studies^d	2 studies (290 participants)^e	⊕⊖⊖⊖ very low^c
Loco‐regional progression	Loco‐regional progression is difficult to interpret in these studies^f	2 studies (186 participants)^g	⊕⊖⊖⊖ very low^c
Quality of life	Quality of life is difficult to interpret in these studies^h	1 study (144 participants)ⁱ	⊕⊖⊖⊖ very low^j
GRADE Working Group grades of evidence   High quality: We are very confident that the true effect lies close to the estimate of effect  Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of effect but may be substantially different  Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of effect  Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect ^aTreatment across trials were heterogenous: Fox 1973 compared surgery to radiotherapy. Lad 1994a administered induction chemotherapy to all participants, and then compared surgery to no surgery; following, all participants had chest and brain irradiation. Liao 1995 administered induction chemotherapy to all participants and then compared surgery to radiotherapy. The effect is difficult to interpret as the types of surgical procedures used in these studies do not reflect current clinical practice. ^bThis includes Fox 1973: surgery ‐ 71 participants; and radiotherapy ‐ 73 participants. Lad 1994a: surgery ‐ 70 participants; and no surgery ‐ 76 participants. Liao 1995: surgery ‐ 20 participants; and radiotherapy ‐ 20 participants. ^cStudies contributing to this outcome were at an unclear risk of bias which reduced our confidence in the estimation of effect. Downgraded once. Staging and surgical techniques don't necessarily reflect best current practice. Downgraded twice. ^dThe effect is difficult to interpret as the type of surgical procedures used in these studies do not reflect current clinical practice. ^eThis includes Fox 1973: surgery ‐ 71 participants; and radiotherapy ‐ 73 participants. Lad 1994a: surgery ‐ 70 participants; and no surgery ‐ 76 participants. ^fTreatments across trials were heterogenous: Fox 1973 compared surgery to radiotherapy. Lad 1994a administered induction chemotherapy to all participants, and then compared surgery to no surgery; following, all participants had chest and brain irradiation. Liao 1995 administered induction chemotherapy to all participants and then compared surgery to radiotherapy. ^gThis includes Lad 1994a: surgery ‐ 70 participants; and no surgery ‐ 76 participants; Liao 1995: surgery ‐ 20 participants; and radiotherapy ‐ 20 participants. ^hFox 1973 reported quality of life and dyspnoea using non‐validated scales. ⁱThis includes Fox 1973: surgery ‐ 71 participants; and radiotherapy ‐ 73 participants. ^jStudies contributing to this outcome were at an unclear risk of bias which reduced our confidence in the estimation of effect. Downgraded once. Staging and surgical techniques don't necessarily reflect best current practice. Downgraded twice. The scales utilised were not validated.