Belyhun et al. BMC Public Health 2010, 10:21 http://www.biomedcentral.com/1471-2458/10/21 Page 5 of 7 Table 3 Univariate analysis of potential risk factors of soil-transmitted helminths in mother and their infants in the Butajira birth cohort, Ethiopia, 2007 Risk factor Soil-transmitted helminths in the mother Soil-transmitted helminths in the child (N = 908) (N = 905) Living in thatched house vs. corrugated sheet Toilet use vs. open field§ Main water source Inside pipe§ Outside pipe∧ Well/stream/rain River Animal spend the night inside Cooking inside the main house Soap use Daily At least once a wk Less frequent than once a week Household waste disposal(N = 904) Buried/Burned Open field Used as fertilizers Maternal helminth infection N(%) 697 (76.8) 564 (62.1) 54 (6.0) 577 (64.0) 118(13.1) 153 (17.0) 573 (63.2) 729 (80.8) 321 (35.4) 532 (58.6) 55 (6.1) 190 (21.0) 248 (27.3) 469 (51.7) 395 (43.5) n(%) 322 (46.2) 234 (41.5) 17 (31.5) 262 (45.4) 47 (39.8) 66 (43.1) 250 (43.6) 334 (45.8) 118 (36.8) 249 (46.8) 28 (50.9) 65 (34.2) 115 (46.4) 215 (45.8) - Crude OR (95%CI) 1.62 (1.18,2.24) 0.81 (0.62,1.06) 1 1.81 (1.00, 3.29) 1.44 (0.73, 2.85) 1.65 (0.86, 3.19) 1.02 (0.78,1.34) 1.68 (1.18,2.37) 1 1.51 (1.14, 2.01) 1.78 (1.00, 3.17) 1 1.66 (1.23,2.46) 1.63 (1.15,2.31) - P-value 0.003 0.080 0.188 0.880 0.003 0.008 0.003♀ 0.013 - n(%) 28 (4.0) 32 (5.7) 10 (18.5) 26 (4.5) 5 (4.3) 3 (2.0) 22 (3.9) 29 (4.0) 19 (5.9) 21 (4.0) 4 (7.4) 9 (4.8) 12 (4.8) 23 (4.9) 22 (5.6) Crude OR (95%CI) 0.51 (0.27,0.96) 1.66 (0.84,3.26) 1 0.21 (0.09, 0.46) 0.20 (0.06, 0.61) 0.09 (0.02, 0.33) 0.57 (0.31,1.04) 0.43(0.23,0.83) 1 0.65 (0.35, 1.23) 1.27 (0.41, 3.88) 1 1.02 (0.42,2.47) 1.04 (0.47,2.28) 1.32 (0.72,2.42) P-value 0.037 0.144 <0.001 0.068 0.012 0.299 0.576♀ 0.996 0.368 §pit latrine, flush type and improvised pit latrine, ♀p for trend $Inside pipe users are those who have a pipe inside the compound and usually used privately. ∧Outside pipe users are those whose source of water is from a pipe outside the compound mainly shared. N = total number of study participants, n = number of outcome for each exposure Table 4 Multivariate analysis of independent risk factors for any soil-transmitted helminth infection in mothers and their children in the Butajira birth cohort, Ethiopia, 2007 Outcome variable Risk factor Adjusted OR 95% CI P-value Maternal infection Soap use 0.055 Daily 1 Trend = 0.018 At least once a week 1.40 1.04, 1.88 Less frequent than once a week 1.66 0.92, 2.99 Urban residence* 0.45 0.28, 0.73 0.001 Domestic animals living together 0.73 0.53, 1.01 0.055 Age of the mother* 0.964 15-24 1 Trend = 0.789 25-34 0.97 0.72, 1.29 35-44 0.95 0.63, 1.44 Child infection Water source 0.002 Inside pipe 1 Outside pipe 0.21 0.09, 0.51 Well/stream/rainwater 0.20 0.56, 0.69 River 0.09 0.02, 0.38 Urban residence* 1.03 0.43, 2.45 0.954 Male gender* 0.67 0.36, 1.26 0.216 * Place of residence included as a priori confounder, and additionally age of the mother in the mother and gender in the child model