The incidence of payments varies little over nuclear or extended households.
Similar to the incidence of payments, nuclear households pay more for their higher educated children.
The higher concentration of catastrophic payments among the poorest households is also confirmed by the negative values of concentration indices for the incidence of catastrophic payment (C_E).
Some of the documented determinants of CHE are poverty, household size, high medical costs, incidence of illness, payment mechanisms, low benefit packages and presence of 'smokers or drinkers' in the household [ 4, 30- 33].
Two of the studies in malfunctioning systems showed increasing risk of GII with increasing water consumption in the tap water group but not in the treated tap water group, by classifying the volume of water intake as a three-level categorical variable and conducting a trend test for the incidence of GII (Payment et al. 1991 , 1997.
The incidence of catastrophic payments is defined as payments in excess of a threshold budget share.
The incidence of catastrophic payments was defined as payments in excess of a threshold budget share and the intensity of catastrophic expenditure was measured by the payment in excess of the threshold, averaged over all households exceeding that threshold [ 16].
We find that due to the widespread informal payments there are no significant differences between households in the incidence of informal payments for households' members, but there are more differences in the amount paid informally.
The variable for the timing of the survey (2002/2005) shows that the incidence of informal payments has decreased for outpatient care for both types of households.
However, a general lack of accountability and good governance combined with the lack of resources has contributed to a high incidence of informal payments in the public health sector [ 11].
The effect of the methods chosen by the household to raise money for health care on the incidence of informal payments does not vary between different types of households.
