Decomposition of Concentration Index Using Generalised Linear Model: Analysis of socio-economic determinants of health inequality in the Northern Territory of Australia

This paper aims to extend the existing linear decomposition techniques for the concentration index to generalised linear models. The second order Taylor expansion is used to derive a linear approximation of the partial concentration indices. This approach adheres closely to the standard decomposition method in the linear settings. The method is illustrated using age-sex standardised mortality rate data from Australia to examine the socioeconomic determinants of Indigenous health inequality. The empirical results demonstrate the usefulness of this method. The new approach provides a more efficient and flexible way to quantify the contributions of the underlying determinants of health inequality in a nonlinear and multivariate context.