. Author manuscript; available in PMC: 2017 Jan 31.

Published in final edited form as: Lancet Haematol. 2016 Feb 27;3(4):e176–e185. doi: 10.1016/S2352-3026(16)00002-8

Table 1. Summary of the 13 case-control studies included in the pooled analysis by country (study name), and years of case accrual.

	Method of assessment	Cases			Controls
		Source	ALL (n)	AML (n)	Source	n
Canada (Quebec), 1980–2000³⁰	Questionnaire	Province-wide hospitals	790	0	Province-wide population-based health-insurance registry	790
Costa Rica, 2001-03³¹	Questionnaire	Cancer registry and hospitals	252	40	Birth registry	577
Egypt (CCHE), 2009–11 (no publication yet)	Questionnaire	One hospital	299	0	Region-wide, population-based registry	351
France (ESCALE), 2003–04³²	Questionnaire	Cancer registry	648	101	Nationwide population quotas	1681
France (ESTELLE), 2010–11¹⁶	Questionnaire	Cancer registry	636	100	Nationwide population quotas	1421
Greece (NARECHEM), 1996–2013¹⁹	Questionnaire	Cancer registry	1045	114	Hospital-based registry	1176
Germany (GCCR), 1980–96²³	Questionnaire	Cancer registry	751	130	Population-based registry	2455
Italy (SETIL), 1998–2001²⁴	Questionnaire	Cancer registry	601	82	Population-based registry	1044
New Zealand (NZCCS), 1990–93²⁵	Questionnaire and medical records	Cancer registry	97	22	Birth registry	303
USA (CCLS), 1995–2013³³	Questionnaire	Hospitals	840	145	Statewide birth registry	1226
USA (CCG), 1989–93³⁴	Questionnaire	CCG clinical trials	1842	450	Random digit dialling^*	2497
USA (Texas), 2003–13³⁵	Questionnaire and medical records	One hospital	212	1	One hospital	339
USA (Washington), 1974–2009³⁶	Birth records	Cancer registry	767	147	Statewide birth registry	9599
Total	..	..	8780	1332	..	23 459

Data are numbers of cases and controls aged 0–14 years contributing to the study sample. ALL=acute lymphoblastic leukaemia. AML=acute myeloid leukaemia. CCHE=Children's Cancer Hospital Egypt. ESCALE=Etude cas-témoins sur les cancers de l'enfant. ESTELLE=Etude cas-témoins sur les cancers de l'enfant. GCCR=German Childhood Cancer Registry. NARECHEM=NAtionwide REgistry for Childhood HaEmatological Malignancies. SETIL=Studio sulla Eziologia dei Tumori Infantili Linfoemopoietici. NZCCS=New Zealand Childhood Cancer Study. CCLS=California Childhood Leukemia Study. CCG=Children's Cancer Group.

Controls were individually matched on telephone area code and exchange.