Table 2.

Estimate of the parameters from the proportional Cox Hazard Model

Predictors	Hazard ratio			Hazard ratios difference
				2000 VS 2011		2005 Vs 2011		2000 Vs 2005
	2000	2005	2011	95 % CI		95 % CI		95 % CI
				Lower	Upper	Lower	Upper	Lower	Upper
Current age of respondent	2.95*	1.01*	0.95*	1.32	2.99**	0.02	0.61**	1.77	1.97**
Age at first birth	1.15*	1.16*	1.05*	0.26	0.77**	0.07	0.28**	0.96	1.00
Age at first sex	1.63	1.01	0.89*	0.75	1.05	0.16	0.42	0.73	0.98
Region (Ref. Oromiya)
Tigray	5.10	4.96	1.17	1.88	4.26**	3.12	5.05**	0.08	0.77
Affar	2.54	2.58	0.82*	0.74	2.67	1.08	2.63**	0.80	1.74**
Amhara	2.88*	2.34*	1.03	1.25	2.96**	0.95	2.08	0.23	0.87**
Somali	1.97	2.46	0.78*	1.29	2.02**	1.03	2.75**	1.20	2.70
Benishangul-Gumz	2.70	2.20	0.93	1.32	3.41**	1.08	3.45**	0.18	0.58**
SNNP	2.79	2.37	0.92	1.92	2.68	1.05	2.81**	0.26	0.89**
Gambela	2.76	2.24	1.07	1.02	2.53**	1.67	2.83	0.41	1.12
Harari	3.22	2.49	1.13	1.46	3.51**	1.14	2.82**	0.62	0.92**
Addis Ababa	0.96	0.76	0.70	0.17	0.72**	0.04	0.52**	0.07	0.56**
Dire Dawa	2.87	2.51	0.91	0.91	1.24	1.11	1.51**	0.23	0.62**
Place of residence (Ref. Urban)
Rural	1.05	0.98	1.19*	0.68	1.12	0.14	0.69**	0.03	0.69**
Highest educational level (Ref. Higher)
No education	2.85*	2.31*	0.79*	2.03	3.08**	1.13	1.91**	0.36	0.92**
Primary	2.91	2.53*	0.82*	2.05	2.85**	0.94	1.42	0.15	0.71**
Secondary	2.93*	2.85	0.87*	2.00	2.78**	1.27	2.07**	0.17	0.86
Religion (Ref. Orthodox)
Muslim	1.76	1.06	1.10*	0.37	0.68**	0.18	0.57	0.21	0.58
Catholic	1.85	1.21	1.01*	1.06	1.39	0.40	0.62	0.15	1.19
Protestant	1.76	0.96	1.09	1.12	1.48	0.26	0.70	0.19	1.34
Traditional	1.55	1.07	0.88	1.15	1.53	0.17	0.79	0.20	0.89**
Other	1.52	1.79	1.71*	0.99	1.44	0.23	0.66	0.19	0.92**
Family size	3.93	1.35	0.99*	2.02	3.84**	0.18	0.88**	1.20	2.28
No of Under five children	1.53	0.99	1.68*	0.54	0.99**	0.58	1.21	0.31	0.88**
Children ever born	1.07*	1.04	1.06*	0.01	0.15**	0.29	0.87	0.07	0.78
Birth in the last five years	3.83*	1.32	1.03	2.00	3.96**	0.17	0.38	1.38	2.73**
Currently pregnant (Ref. No)
Yes	0.98	1.03	1.06	0.14	0.82	0.09	0.21	0.03	0.65
Type of birth (Ref. Single birth)
1st of multiple	0.56*	0.79	1.18	0.52	1.43	0.35	0.91**	0.81	0.85
2nd of multiple	1.05	1.14	2.00	0.50	1.56	0.15	0.79	0.04	0.56**
3rd of multiple	1.39	1.38*	0.56*	0.48	0.85**	0.74	1.10	0.06	0.25
Sex of the child (Ref. Female)
Male	1.08	1.19	1.09*	0.01	0.34**	0.04	0.33**	0.07	0.28**
Toilet facility (Ref. Pit latrine)
Flush toilet	3.92	0.73	1.13	0.37	1.94	0.59	1.27	2.03	3.10
No facility	1.02	0.92	1.01	0.48	1.98	0.16	2.01	0.63	0.72
Type of fuel (Ref. Charcoal/wood etc.)
Electricity	1.10	2.19	2.16*	0.77	1.23	0.24	0.84	0.81	1.22
Gas/LPG	0.43*	0.39*	1.35	0.44	0.84	0.40	0.89	0.01	0.37**
No food cooked	1.13	1.01	0.63	0.99	1.09	0.35	1.12	0.18	0.74
Floor material (Ref. Carpet)
Cement	1.05	0.73	1.12	0.20	1.43	0.30	2.06	0.65	1.24
Natural floor	1.15	0.92	0.94	0.03	1.93	0.95	2.37	0.57	1.17
Wood/ceramics	1.56*	0.63	0.77	0.83	1.02	0.62	1.09	0.49	1.10
Roof material (Ref. Thatch/Plastic/wood)
Finished roofing	1.15	0.93	1.00	0.69	1.04	0.73	1.42	0.28	0.83
No roof	1.56	0.95	0.99	0.04	1.99	0.20	1.72	0.74	1.26
Wall material (Ref. Finished walls)
No walls	1.06	0.93	0.82	0.98	1.33	0.58	1.28	0.25	0.69
Cane/bamboo/wood	0.99	1.04	0.81*	0.80	1.96	0.92	1.80	0.11	0.25

* Significant at 5 % level of significance

**Significant interaction effects