Table 4

Multilevel regression modelling of association between high-risk fertility behaviour and childhood anaemia

VariablesModel 0Model I
aOR (95% CI)
Model II
aOR (95% CI)
Fixed effects
Key explanatory variables
Age less than 18 at birth
 No1 (1.00 to 1.00)1 (1.00 to 1.00)
 Yes1.34*** (1.20 to 1.50)0.99 (0.84 to 1.18)
Age more than 34 at birth
 No1 (1.00 to 1.00)1 (1.00 to 1.00)
 Yes0.80*** (0.76 to 0.85)0.89*** (0.83 to 0.95)
Short birth interval
 No1 (1.00 to 1.00)1 (1.00 to 1.00)
 Yes1.09* (1.02 to 1.17)1.08* (1.01 to 1.16)
High parity
 No1 (1.00 to 1.00)1 (1.00 to 1.00)
 Yes1.21*** (1.15 to 1.27)1.06 (0.98 to 1.14)
Random effects
PSU variance (95% CI)0.067 (0.051 to 0.088)0.067 (0.051 to 0.087)0.076 (0.058 to 0.100)
ICC0.01998810.01988410.0226424
Wald χ2Reference100.69 (<0.001)3844.34 (<0.001)
Model fitness
 Log-likelihood−40668.23−40581.826−37392.375
 AIC81340.4681175.6574854.75
 n64 51264 51264 512
 Clusters (n)137513751375
  • Exponentiated coefficients; 95% CIs in brackets. *P<0.05; **p<0.01; ***p<0.001. 1=Reference category .

  • Model 0: empty model with no explanatory variables.

  • Model I: contained only the key explanatory variables.

  • Model II: contained the key explanatory variables and covariates.

  • AIC, Akaike’s information criterion; aOR, adjusted OR; ICC, intraclass correlation; PSU, primary sampling unit.