Table 1. Characteristics of case-control studies examining the relationship between family history and risk of lung cancer.

			Cases	Controls						Standardising variables
Study	Region/country	Years of data collection	Number	Number	Type	Data sources a	Type of relative	Sex of cases	Recall bias	Age	Smokingb (case/relative)	Family size	Other
Tokuhata (1963b)	Maryland, USA	1960–61	270	270	Community	IS, NOK, OR, DC	1st degree	Both	Yes	Yes	Yes (qual)/yes (qual)	Yes	No
Tokuhata (1963a)	New York, USA	1957–60	361	722	Hospital (cancer free)	IS, NOK, DC	Parent/sibling	Both	Yes	Yes	No/no	No	Race, residence
Ooi (1986)	Louisiana, USA	1976–79	336	307	Spouse	IS, NOK, OR, DC	1st degree	Both	Yes	Yes	Yes (quant)/no	No	Occupation
Samet (1986)	New Mexico, USA	1980–82	518	769	Community	IS, NOK	Parent	Both	Yes	Yes	Yes (quant)/no	No	Ethnicity
Gao (1987)	Shanghai, China	1984–86	672	735	Community	IS	Parent	Female	Yes	Yes	Yes (quant)/no	No	Education
Kramer (1987)	New York, USA	N/Ac	427	467	N/A	IS, NOK, TR	1st degree	Both	No	Yes	No/yes (qual)	No	Occupation
Tsugane (1987)	Tokyo, Japan	1976–85	185	185	Hospital (cancer free)	MR	1st/2nd degree	Both	Yes	Yes	No/no	No	Residence
Horwitz (1988)	New Haven, USA	1977–82	112	224	Hospital (nonsmoking-related cancers/cancer free)	MR	Parent/sibling	Female	Yes	Yes	No/no	No	Ethnicity
Wu (1988)	Los Angeles, USA	1983–86	336	336	Community	IS	Parent/sibling	Female	Yes	Yes	Yes (quant)/no	No	Ethnicity
McDuffie (1989)	Saskatchewan, Canada	1979–83	931	1031	Community	IS, NOK	1st degree	Both	Yes	Yes	No/no	No	Residence
Wu-Williams (1990)	Shenyang, China	1985–87	965	959	Community	IS	1st degree	Female	Yes	Yes	Yes (quant)/no	No	Education
Liu (1991)	Xuanwei, China	1985–86	110	426	Community	IS	1st/2nd degree	Both	Yes	Yes	Yes (quant)/no	No	Residence
Osann (1991)	California, USA	1969–77	208	208	Screening programme	IS	1st degree	Female	No	Yes	Yes (quant)/ no	No	Education, ethnicity
McDuffie (1991)	Saskatchewan, USA	1983–86	359	234	Community	IS, OR, MR, TR	Parent/sibling	Both	Yes	Yes	No/no	Yes	Residence
Shaw (1991)	Texas, USA	1976–80	937	955	Community	IS, NOK	1st degree	Both	Yes	Yes	Yes (quant)/no	Yes	Ethnicity, residence, ETSd
Pavlakou (1993)	Athens, Greece	1993	85	140	Community (cancer free)	IS	1st degree	Female	Yes	Yes	No/no	No	Ethnicity
Schwartz (1996)	Detroit, USA	1984–87	257	277	Community	IS, NOK, OR	1st degree	Both	Yes	Yes	N/a/no	No	Ethnicity, ETS, occupation
Wang (1996)	Guangdong, China	1990–93	390	390	Hospital (cancer free)	IS	N/A	Both	Yes	Yes	Yes (qual)/no	No	Residence, education
Wu (1996)	USA	1985–90	626	1240	Community	IS, NOK, OR	1st degree	Female	Yes	Yes	Yes (quant)/yes (qual)	Yes	Residence, ethnicity, education, ETS
Brownson (1997)	Missouri, USA	1986–91	618	1402	Community	IS, NOK, OR	1st degree	Female	Yes	Yes	No/yes (qual)	Yes	Ethnicity
Kreuzer (1998)	Germany	1990–96	2260	2319	Community	IS	Parent/sibling	Both	Yes	Yes	Yes (quant)/no	Yes	Residence, asbestos exposure
Mayne (1999)	New York, USA	1982–84	437	437	Community	IS, NOK, OR	1st degree	Both	Yes	Yes	No/no	Yes	Residence
Bromen (2000)	Bremen, Germany	1988–93	945	983	Community	IS	1st degree	Both	Yes	Yes	Yes (quant)/yes (qual)	Yes	Residence, ethnicity, asbestos exposure
Wunsch-Filho (2002)	Sao Paolo, Brazil	1989–91	285	578	Hospital (non-smoking related cancers/cancer free)	IS	1st degree	Both	Yes	Yes	Yes (quant)/no	No	Socioeconomic status
Etzel (2003)	Houston, USA	1995–00	806	663	Multidisciplinary clinic	IS	1st degree	Both	Yes	Yes	Yes (quant)/yes (qual)	No	Ethnicity
Wu (2004)	Taiwan	1992–02	108	108	Hospital (cancer free)	IS, NOK	1st degree	Female	Yes	Yes	No/no	No	Education, ETS, smoky coal exposure
Jin (2005)	Xuanwei, China	1992–99	740	740	Spouse	IS, NOK, OR, DC	1st degree	Both	Yes	Yes	Yes (quant)/no	Yes	Residence, smoky coal exposure
Matakidou (2005)	UK	1999–04	1482	1079	Spouse	IS	1st degree	Female	Yes	Yes	Yes (quant)/no	No	Ethnicity

^aData sources: IS=index subject; NOK=next of kin; OR=other relative; DC=death certificates; TR=tumour registry; MR=medical records.

^bQual=qualitative; quant=quantitative.

^cN/A=not available.

^dETS=environmental tobacco smoke.