Akl et al. BMC Public Health 2011, 11:244 http://www.biomedcentral.com/1471-2458/11/244 Table 1 Summary of included studies (Continued) Page 6 of 12 Maziak 2004 [9,26-28] Syria, 2003 Gadalla 2003 [29] Egypt, 2002/03 Habib 2000 [30] Egypt, 1997 El Sadawy 2004[31] Egypt Medhat 2002 [32] Egypt South Asia Jawaid 2008 [42] Pakistan, 2006-2007 Nisar 2007 [44] Pakistan, 2005 Nisar 2005 [43] Pakistan Alam 1998 [45] Pakistan, 1990-1994 Primack 2008 [50] USA, 2007 Weglicki 2008 [46,47] USA, 2004-2005 Rice 2007 [48] USA Rice 2006 [11] USA, 2001/02 Ward 2006 [51] USA, 2000 - 2002 Americas Primack 2009 [49] USA, 2004/05 Europe Jackson 2008 [12] United Kingdom Parna 2008 [52] Estonia, 2006-2007 Australia Carroll 2008 [13,53] Australia, 2004 Aleppo University students (47% males; mean age 22); Current: 15% (M 26%, F 5%) N = 587 Students of secondary schools in villages; N = 627 Ever: 46% (M 62.6%, F 230%) Lifetime: 19% (M: 26%, F: 5%) Males in households of a village; N = 1827 Group water pipe smoking: (males only) 10.6% Males in household in Sharkia Governorate; N = 782 Group water pipe smoking (males only): 14.6% Male village inhabitants 5 years and older; N = 2717 Group water pipe smoking: 13% (> 30 years: 7%) University students, Karachi (60% males; mean age 21); Current: 33% N = 450 Ever: 54% (M 64%; F 38%) Adults living in semi urban community (64% males); N Overall: 13% = 157 Adult females in Karachi; N = 200 Overall: 41% Adults (in urban and rural areas (47%males); N = 9441 Overall: 6% (M 7%; F6%) University studeents (mean age 21; 34% males); N = 647 Arab-American and non-Arab-American youth (14-18); N = 1872 Past 30 days: 10% Ever: 41% Arabs (current): 17% Non Arabs (current): 11% Arab and non-Arab Americans (mean age 15; 55% M); Arab: last 30 days 12%; regular 8%; Other: last 30 days 4%, N = 1455 regular 3% Adolescents (mean age 15, 52% males); N = 1671 Active duty Air Force personnel; N = 20,673 School students (48% males; median age 14); N = 6,594 University students (42% males); N = 937 11-15 year old school students (50% males); N = 4463 Arabic speakers in Australia; N not reported Experimentation: 27% Ever by age 14: 23% Ever by age 18: 40% Overall: 0.3% Past 30 days: 4% Ever: 6% Ever: 38% Regular: 8% Current: 21% (M 25%; F 16%) Daily: 0.8% (M 1% F 0.3%) Current: 11% Daily: 1%