Table 2 Studies included in the meta-analyses
Study | Health Outcomes# | Study Type | Number of Subjects^ | Controlled for Age, Sex, Smoking and Socioeconomic Status | |
|---|---|---|---|---|---|
Bakke et al. 2007 | [29] | RI | cross sectional | 173 | Yes |
Biagini et al. 2006 | [10] | RI | birth cohort | 585 | Yes |
Brunekreef et al. 1989 | [30] | B | cross sectional | 4,625 | Yes |
Dales et al. 1991 | [31] | B | cross sectional | 13,495 | No |
Diez et al. 2003 | [32] | B | birth cohort | 172 - 178 | No |
du Prel et al. 2006 | [33] | RI, B | cross sectional | 5,757 - 20,059 | Yes |
Ekici et al. 2008 | [34] | RI, B | cross sectional | 9,610 - 9,853 | Yes (BR) No (RI) |
Haverinen et al. 2001 | [8] | RI, B | cross sectional | 1,017 | Yes |
Karevold et al. 2006) | [35] | RI | cross sectional | 275 - 737 | Yes |
Kilpelainen et al. 2001 | [36] | RI | cross sectional | 9,765 - 10,504 | No |
Koskinen et al. 1999 | [37] | RI, B | cross sectional | 57 - 147 | No |
Li and Hsu 1996 | [38] | RI, B | cross sectional | 1,340 | Yes |
Pettigrew et al. 2004 | [39] | RI* | birth cohort | 806 | No |
Pirhonen et al. 1996 | [40] | RI, B | cross sectional | 1,460 | Yes |
Rylander and Megevand 2000 | [41] | RI, B** | cross sectional | 304 | No |
Spengler et al. 1994 | [42] | B | cross sectional | 12,842 | No |
Spengler et al. 2004 | [43] | RI, B | cross sectional | 5,951 | Yes |
Stark et al. 2003 | [7] | RI | birth cohort | 499 | Yes |
Strachan 1988 | [44] | RI | cross sectional | 873 | No |
Sun et al. 2009 | [45] | RI | cross sectional | 3,436 | Yes |
van Gageldonk-Lafeber et al. 2007 | [9] | RI | case-control | 626 | No |
Yang et al. 1997 | [46] | RI, B | cross sectional | 4,164 | Yes |
Yang et al. 1999 | [47] | RI* | case control | 438 | Yes |