Table 3

Childhood factors and risk of UC

	Unadjusted (Asia only)			Adjusted# (Asia only)			Adjusted# (Asia and Australia)
	OR	95% CI	p Value	OR	95% CI	p Value	OR	95% CI	p Value
Breast feeding§
0–6 months	1	–	–	1	–	–	1.000	–	–
7–12 months	1.344	0.906 to 1.994	0.141	1.138	0.758 to 1.709	0.533	1.050	0.708 to 1.557	0.809
>12 months	0.226	0.117 to 0.435	0†	0.159	0.081 to 0.313	0†	0.142	0.073 to 0.277	0†
Tonsillectomy	0.487	0.110 to 2.157	0.343	0.506	0.113 to 2.255	0.371	0.831	0.340 to 2.031	0.831
Appendectomy	0.446	0.133 to 1.498	0.191	0.437	0.129 to 1.474	0.182	0.384	0.135 to 1.092	0.073
Eczema	0.889	0.533 to 1.480	0.650	1.036	0.614 to 1.751	0.893	1.295	0.783 to 2.141	0.315
Antibiotic use§
≤15 years	0.441	0.245 to 0.791	0.006	0.484	0.267 to 0.874	0.016	0.503	0.279 to 0.907	0.022
>15 years	0.784	0.498 to 1.234	0.293	0.771	0.488 to 1.220	0.267	0.743	0.470 to 1.173	0.203
Pet animals
Dog	0.846	0.623 to 1.150	0.286	0.818	0.601 to 1.115	0.204	0.796	0.591 to 1.071	0.132
Cat	0.736	0.497 to 1.089	0.125	0.693	0.466 to 1.031	0.070	0.717	0.494 to 1.041	0.080
Rodents	0.978	0.491 to 1.949	0.950	1.162	0.575 to 2.350	0.675	1.187	0.611 to 2.305	0.613
Birds	0.582	0.323 to 1.049	0.072	0.624	0.344 to 1.129	0.119	0.685	0.404 to 1.160	0.160
Aquarium fish	0.417	0.266 to 0.652	0†	0.463	0.292 to 0.734	0.001	0.479	0.308 to 0.745	0.001
Vaccinations§
BCG	0.638	0.382 to 1.063	0.085	0.807	0.465 to 1.402	0.448	1.302	0.796 to 2.131	0.293
Pertussis	0.541	0.346 to 0.847	0.007	0.614	0.378 to 0.998	0.049	0.602	0.373 to 0.970	0.037
Measles	0.647	0.411 to 1.018	0.060	0.774	0.472 to 1.271	0.312	0.837	0.527 to 1.328	0.449
Rubella	0.568	0.372 to 0.866	0.009	0.735	0.463 to 1.167	0.192	0.747	0.475 to 1.177	0.208
Diphtheria	0.588	0.370 to 0.937	0.025	0.727	0.440 to 1.201	0.213	0.722	0.442 to 1.181	0.195
Tetanus	0.572	0.364 to 0.900	0.016	0.661	0.405 to 1.078	0.097	0.670	0.436 to 1.144	0.158
Polio	0.596	0.375 to 0.946	0.028	0.681	0.413 to 1.124	0.133	1.012	0.413 to 1.089	0.106
Childhood infections§
Measles	0.963	0.585 to 1.584	0.880	0.941	0.567 to 1.559	0.812	1.012	0.626 to 1.636	0.962
Pertussis	0.965	0.203 to 4.586	0.965	0.941	0.196 to 4.511	0.939	0.916	0.191 to 4.382	0.912
Rubella	0.314	0.040 to 2.451	0.269	0.353	0.045 to 2.773	0.322	0.318	0.041 to 2.475	0.274
Chickenpox	0.743	0.529 to 1.044	0.087	0.802	0.564 to 1.141	0.219	0.839	0.595 to 1.182	0.316
Mumps	0.845	0.537 to 1.329	0.466	0.822	0.520 to 1.300	0.402	0.806	0.515 to 1.264	0.348
Scarlet fever	6.247	1.036 to 37.680	0.046	5.924	0.979 to 35.845	0.053	3.951	0.789 to 19.778	0.095
Sanitary conditions
Inhouse water tap	0.597	0.441 to 0.807	0.001	0.667	0.477 to 0.932	0.018	0.681	0.488 to 0.949	0.023
Hot water tap	0.578	0.426 to 0.784	0†	0.647	0.460 to 0.910	0.012	0.580	0.415 to 0.810	0.001
Flush toilet	0.618	0.461 to 0.830	0.001	0.707	0.508 to 0.983	0.039	0.727	0.525 to 1.008	0.056

Statistically significant results are shown in bold (p<0.05).
*Adjusted for sex, age and country income based on GNI.
†Significant at p<0.0006 level after Bonferroni adjustment.
§>20% ‘unsure’ responses for one of more subject categories.
GNI, gross national income.