Table 3 The adjusted and unadjusted hazard ratios from fitting the Cox-proportional hazard model for only those covariates that satisfy the proportionality hazard assumption

Father’s education

 Illiterate

1

1

 Primary

0.89 \(\left[ 0.74, 1.08\right]\)

0.92 \(\left[ 0.76,1.12\right]\)

0.43

 Secondary and higher

0.67 \(\left[ 0.48, 0.92\right]\)

0.72 \(\left[ 0.51 , 1.01\right]\)

0.06

Sex of the child

 Male

1

 Female

0.83 \(\left[ 0.69, 0.99\right]\)

0.83 \(\left[ 0.69,0.99\right]\)

0.04

Age at first birth

 <20

1

1

 20–29

0.84 \(\left[ 0.68, 1.02\right]\)

0.86 \(\left[ 0.69,1.06\right]\)

0.16

 30+

1.52 \(\left[ 0.49,4.73\right]\)

1.59 \(\left[ 0.51,5.02\right]\)

0.42

Sex of household head

 Male

1

1

 Female

1.30 \(\left[ 1.07 , 1.59\right]\)

1.33 \(\left[ 1.09, 1.63\right]\)

0.01

Number of births in the past 1 year

 No birth

1

1

 1 birth

1.18 \(\left[ 0.98,1.43\right]\)

1.22 \(\left[ 1.01,1.48\right]\)

0.04

 2 births

2.34 \(\left[ 0.97,5.67\right]\)

2.57 \(\left[ 1.06,6.25\right]\)

0.04

Mother’s age (years)

 <20

1

1

 20–29

0.66 \(\left[ 0.45 ,0.98\right]\)

0.71 \(\left[ 0.48,1.05\right]\)

0.08

 30–39

0.74 \(\left[ 0.50,1.10\right]\)

0.79 \(\left[ 0.53,1.19\right]\)

0.27

 40+

0.90 \(\left[ 0.57,1.43\right]\)

0.99 \(\left[ 0.62,1.59\right]\)

0.98

Source of drinking water

 Piped water

1

1

 Borehole

1.24 \(\left[ 0.96, 1.62\right]\)

1.12 \(\left[ 0.86,1.48\right]\)

0.39

 Well water

1.17 \(\left[ 0.86 , 1.58\right]\)

1.06 \(\left[ 0.78,1.45\right]\)

0.69

Surface/pond/lake/rain/etc

1.44 \(\left[ 1.04, 1.98\right]\)

1.28 \(\left[ 0.91,1.79\right]\)

0.15

 Others

1.32 \(\left[ 0.82, 2.13\right]\)

1.21 \(\left[ 0.75,1.94\right]\)

0.44

Religion

 Catholic

1

1

 Muslim

1.01 \(\left[ 0.77,1.33\right]\)

1.02 \(\left[ 0.77,1.34\right]\)

0.91

 Other Christians

0.91 \(\left[ 0.75,1.11\right]\)

0.94 \(\left[ 0.77,1.14\right]\)

0.51

 Others

0.717 \(\left[ 0.27,1.93\right]\)

0.67 \(\left[ 0.25,1.81\right]\)

0.43