Appendix 1. Search strategy for Cochrane Central Register of Controlled Trials (CENTRAL)

(1) For ifosfamide the following subject headings and text words were used:

(ifosfamide OR iphosphamide OR iso‐endoxan OR iso endoxan OR isophosphamide OR isofosfamide OR holoxan OR asta z 4942 OR NSC‐109,724 OR NSC 109,724 OR NSC109,724 OR NSC 109724 OR NSC‐109724 OR NSC109724 OR cyclic p‐oxides OR ethylamines OR oxazines OR ifosfa* OR iphospha* OR isofosfa* OR isophospha*) in Clinical Trials

(2) For cyclophosphamide the following subject headings and text words were used:

(cyclophosphamide OR cyclophosphane OR cytophosphan OR B‐518 OR cyclophosphamide monohydrate OR endoxan OR cytoxan OR neosar OR procytox OR sendoxan OR NSC‐26271 OR NSC 26271 OR NSC26271 OR endox* OR cyclophospha*) in Clinical Trials

(3) For sarcoma the following subject headings and text words were used:

(sarcoma OR sarcomas OR soft tissue sarcoma OR soft tissue sarcomas OR epithelioid sarcoma OR epithelioid sarcomas OR spindle cell sarcoma OR spindle cell sarcomas OR sarcom* OR adenosarcoma OR adenosarcom* OR carcinosarcoma OR carcinosarcom* OR chondrosarcoma OR chondrosarcom* OR fibrosarcoma OR fibrosarcom* OR dermatofibrosarcoma OR dermatofibrosarcom* OR neurofibrosarcoma OR neurofibosarcom* OR neurogenic sarcoma OR hemangiosarcoma OR hemangiosarcom* OR haemangiosarcom* OR angiosarcoma OR angiosarcom* OR leiomyosarcoma OR leiomyosarcom* OR liposarcoma OR liposarcom* OR lymphangiosarcoma OR lymphangiosarcom* OR myxosarcoma OR myxosarcom* OR synovial sarcoma OR sarcoma synovial OR small cell sarcoma OR granulocytic sarcoma OR alveolar soft part sarcoma OR clear cell sarcoma OR osteosarcoma OR osteosarcomas OR osteosarcom* OR osteogenic sarcoma OR osteogenic sarcomas OR juxtacortical osteosarcoma OR juxtacortical osteosarcomas OR rhabdomyosarcoma OR rhabdomyosarcomas OR rhabdomyosarcom* OR myosarcoma OR myosarcomas OR myosarcom* OR embryonal rhabdomyosarcoma OR embryonal rhabdomyosarcomas OR alveolar rhabdomyosarcoma OR alveolar rhabdomyosarcomas OR ewing's sarcoma OR ewing tumor OR ewing tumors OR ewing's tumor OR tumor ewing's OR ewing*) in Clinical Trials

The different searches were combined as (1) AND (2) AND (3).

Appendix 2. Search strategy for MEDLINE/PubMed

(1) For ifosfamide the following subject headings and text words were used:
ifosfamide OR iphosphamide OR iso‐endoxan OR iso endoxan OR isophosphamide OR isofosfamide OR holoxan OR asta z 4942 OR NSC‐109,724 OR NSC 109,724 OR NSC109,724 OR NSC 109724 OR NSC‐109724 OR NSC109724 OR cyclic p‐oxides OR ethylamines OR oxazines OR ifosfa* OR iphospha* OR isofosfa* OR isophospha*

(2) For cyclophosphamide the following subject headings and text words were used:
cyclophosphamide OR cyclophosphane OR cytophosphan OR B‐518 OR cyclophosphamide monohydrate OR monohydrate, cyclophosphamide OR endoxan OR cytoxan OR neosar OR procytox OR sendoxan OR NSC‐26271 OR NSC 26271 OR NSC26271 OR cyclophosphamide, (R)‐isomer OR cyclophosphamide, (S)‐isomer OR cyclophosphamide, (+)‐isomer OR endox* OR cyclophospha*

(3) For sarcoma the following subject headings and text words were used:
sarcoma OR sarcomas OR sarcoma, soft tissue OR sarcomas, soft tissue OR soft tissue sarcoma OR soft tissue sarcomas OR sarcoma, epithelioid OR epithelioid sarcoma OR epithelioid sarcomas OR sarcomas, epithelioid OR sarcoma, spindle cell OR sarcomas, spindle cell OR spindle cell sarcoma OR spindle cell sarcomas OR sarcom* OR adenosarcoma OR adenosarcom* OR carcinosarcoma OR carcinosarcom* OR chondrosarcoma OR chondrosarcom* OR fibrosarcoma OR fibrosarcom* OR dermatofibrosarcoma OR dermatofibrosarcom* OR neurofibrosarcoma OR neurofibosarcom* OR neurogenic sarcoma OR hemangiosarcoma OR hemangiosarcom* OR haemangiosarcom* OR angiosarcoma OR angiosarcom* OR leiomyosarcoma OR leiomyosarcom* OR liposarcoma OR liposarcom* OR lymphangiosarcoma OR lymphangiosarcom* OR myxosarcoma OR myxosarcom* OR synovial sarcoma OR sarcoma synovial OR sarcoma, small cell OR small cell sarcoma OR sarcoma, granulocytic OR granulocytic sarcoma OR sarcoma, alveolar soft part OR alveolar soft part sarcoma OR sarcoma, clear cell OR clear cell sarcoma OR osteosarcoma OR osteosarcomas OR osteosarcom* OR osteogenic sarcoma OR osteogenic sarcomas OR sarcoma, osteogenic OR sarcomas, osteogenic OR osteosarcoma, juxtacortical OR osteosarcomas, juxtacortical OR juxtacortical osteosarcoma OR juxtacortical osteosarcomas OR rhabdomyosarcoma OR rhabdomyosarcomas OR rhabdomyosarcom* OR myosarcoma OR myosarcomas OR myosarcom* OR embryonal rhabdomyosarcoma OR embryonal rhabdomyosarcomas OR rhabdomyosarcomas, embryonal OR alveolar rhabdomyosarcoma OR alveolar rhabdomyosarcomas OR rhabdomyosarcomas, alveolar OR sarcoma, ewing's OR ewing's sarcoma OR sarcoma, ewing OR sarcoma, ewings OR ewing tumor OR ewing tumors OR ewing's tumor OR tumor ewing's OR ewing*

The different searches were combined as (1) and (2) and (3) and the highly sensitive search strategy for RCTs and CCTs (Higgins 2005 (September 2006) / Higgins 2008 (November 2008 when updating the original search and March 2012 and March 2015 for the review updates)).

(RCT: randomised controlled trial; CCT: controlled clinical trial).

Appendix 3. Search strategy for EMBASE/Ovid

(1) For cyclophosphamide the following subject headings and text words were used:

((cyclophosphamide or cyclophosphane or cytophosphan or B‐518 or cyclophosphamide monohydrate or endoxan or cytoxan or neosar or procytox or sendoxan or NSC‐26271 or NSC 26271 or NSC26271 or endox$ or cyclophospha$ or cyclofosfa$).mp) or cyclophosphamide/ or cyclophosphamide derivative/ or 50‐18‐0.rn

(2) For ifosfamide the following subject headings and text words were used:

((ifosfamide or iphosphamide or iso‐endoxan or iso endoxan or isophosphamide or isofosfamide or holoxan or asta z 4942 or NSC‐109,724 or NSC 109,724 or NSC109,724 or NSC 109724 or NSC‐109724 or NSC109724 or cyclic p‐oxides or ethylamines or oxazines or ifosfa$ or iphospha$ or isofosfa$ or isophospha$).mp) or ifosfamide/ or 3778‐73‐2.rn

(3) For sarcoma the following subject headings and text words were used:

((sarcoma or sarcomas or soft tissue sarcoma or soft tissue sarcomas or epithelioid sarcoma or epithelioid sarcomas or spindle cell sarcoma or spindle cell sarcomas or sarcom$ or adenosarcoma or adenosarcom$ or carcinosarcoma or carcinosarcom$ or chondrosarcoma or chondrosarcom$ or fibrosarcoma or fibrosarcom$ or dermatofibrosarcoma or dermatofibrosarcom$ or neurofibrosarcoma or neurofibosarcom$ or neurogenic sarcoma or hemangiosarcoma or hemangiosarcom$ or haemangiosarcoma or haemangiosarcom$ or angiosarcoma or angiosarcom$ or leiomyosarcoma or leiomyosarcom$ or liposarcoma or liposarcom$ or lymphangiosarcoma or lymphangiosarcom$ or myxosarcoma or myxosarcom$ or synovial sarcoma or small cell sarcoma or granulocytic sarcoma or alveolar soft part sarcoma or clear cell sarcoma or osteosarcoma or osteosarcomas or osteosarcom$ or osteogenic sarcoma or osteogenic sarcomas or juxtacortical osteosarcoma or juxtacortical osteosarcomas or rhabdomyosarcoma or rhabdomyosarcomas or rhabdomyosarcom$ or myosarcoma or myosarcomas or myosarcom$ or embryonal rhabdomyosarcoma or embryonal rhabdomyosarcomas or alveolar rhabdomyosarcoma or alveolar rhabdomyosarcomas or ewing's sarcoma or ewings sarcoma or ewing tumor or ewing tumors or ewing's tumor or ewing$).mp) or ((bone sarcoma or soft part sarcoma or chondroblastic sarcoma).mp) or soft tissue sarcoma/ or ewing sarcoma/ or sarcoma/ or epithelioid sarcoma/ or spindle cell sarcoma/ or adenosarcoma/ or carcinosarcoma/ or chondrosarcoma/ or fibrosarcoma or dermatofibrosarcoma protuberans/ or neurofibrosarcoma/ or angiosarcoma/ or liposarcoma/ or leiomyosarcoma/ or lymphangiosarcoma/ or myxosarcoma/ or synovial sarcoma/ or small cell sarcoma/ or granulocytic sarcoma/ or alveolar soft part sarcoma/ or clear cell sarcoma/ or osteosarcoma/ or juxtacortical osteosarcoma/ or rhabdomyosarcoma/ or embryonal rhabdomyosarcoma/ or myosarcoma/

(4) For RCTs and CCTs the following subject headings and text words were used (based on the highly sensitive search strategy for RCTs and CCTs of Higgins 2005):

(a) clinical trial/ or controlled study/ or randomized controlled trial/ or double blind procedure/ or single blind procedure/ or comparative study/ or randomization/ or prospective study/ or placebo/ or phase 2 clinical trial/ or phase 3 clinical study.mp or phase 4 clinical study.mp or phase 3 clinical trial/ or phase 4 clinical trial/ or allocat$.mp or blind$.mp or control$.mp or placebo$.mp or prospectiv$.mp or random$.mp or ((singl$ or doubl$ or trebl$ or tripl$) and (blind$ or mask$)).mp or (versus or vs).mp or (randomized controlled trial$ or randomised controlled trial$).mp or controlled clinical trial$.mp or clinical trial$.mp
(b) human/ or nonhuman/ or animal/ or animal experiment/
(c) (b) NOT human/
(d) (a) NOT (c)

When updating the original search in November 2008 and in March 2012 and 2015 we used the following search based on the highly sensitive search strategy for RCTs and CCTs of Higgins 2008:

(a) randomized controlled trial or controlled clinical trial).mp or (randomized or placebo or randomly or trial or groups).ti,ab or drug therapy.sh
(b) limit (a) to human

The different searches were combined as (1) AND (2) AND (3) AND (4).

mp: title, abstract, subject headings, drug trade name, original title, device manufacturer, drug manufacturer name; ti,ab: title, abstract; sh: subject heading; rn: chemical abstract services registration number; RCT: randomized controlled trial; CCT: controlled clinical trial