Background: The fifth Millennium Development Goal (MDG5) aims at improving maternal health. Globally, the maternal mortality ratio (MMR) declined from 400 to 260 per 100000 live births between 1990 and 2008. During the same period, MMR in sub-Saharan Africa decreased from 870 to 640. The decreased in MMR has been attributed to increase in the proportion of deliveries attended by skilled health personnel. Global improvements maternal health and health service provision indicators mask inequalities both between and within countries. In Namibia, there are significant inequities in births attended by skilled providers that favour those that are economically better off. The objective of this study was to identify the drivers of wealth-related inequalities in child delivery by skilled health providers.Methods: Namibia Demographic and Health Survey data of 2006-07 are analysed for the causes of inequities in skilled birth attendance using a decomposable health concentration index and the framework of the Commission on Social Determinants of Health.Results: About 80.3% of the deliveries were attended by skilled health providers. Skilled birth attendance in the richest quintile is about 70% more than that of the poorest quintile. The rate of skilled attendance among educated women is almost twice that of women with no education. Furthermore, women in urban areas access the services of trained birth attendant 30% more than those in rural areas. Use of skilled birth attendants is over 90% in Erongo, Hardap, Karas and Khomas Regions, while the lowest (about 60-70%) is seen in Kavango, Kunene and Ohangwena. The concentration curve and concentration index show statistically significant wealth-related inequalities in delivery by skilled providers that are to the advantage of women from economically better off households (C = 0.0979; P < 0.001).Delivery by skilled health provider by various maternal and household characteristics was 21 percentage points higher in urban than rural areas; 39 percentage points higher among those in richest wealth quintile than the poorest; 47 percentage points higher among mothers with higher level of education than those with no education; 5 percentage points higher among female headed households than those headed by men; 20 percentage points higher among people with health insurance cover than those without; and 31 percentage points higher in Karas region than Kavango region.Conclusion: Inequalities in wealth and education of the mother are seen to be the main drivers of inequities in the percentage of births attended by skilled health personnel. This clearly implies that addressing inequalities in access to child delivery services should not be confined to the health system and that a concerted multi-sectoral action is needed in line with the principles of the Primary health Care. © 2011 Zere et al; licensee BioMed Central Ltd.
In measuring equity in a health outcome or access to health interventions, the following are required: – indicator of the health intervention of interest (delivery by skilled health providers) – a variable (stratifier) capturing socio-economic status against which the distribution is to be assessed (wealth); and – a measure of socio-economic inequality to quantify the degree of inequity in the indicator variable of interest. A concentration index (C) is used to measure wealth-related inequalities in the observed use of delivery services by skilled health providers. The concentration index of a health care variable y (utilization of delivery services by trained health providers) can be defined using the concentration curve that links the cumulative proportion of individuals ranked by wealth to the corresponding cumulative proportion of y (use of delivery services by trained health providers). The concentration curve plots shares of the health care variable (y) against quantiles of the measure of socio-economic status (asset-based wealth index) [17]. The concentration index is defined as twice the area between the concentration curve and the line of equality and assumes values between -1 and +1. A negative value of the concentration index denotes inequity in skilled care at birth that is to the advantage of the lower wealth quintiles implying that women of lower socio-economic status are delivered by skilled health providers more than their counterparts who are wealthier. In this case the concentration curve lies above the line of equality. On the other hand, a positive concentration index implies inequality in the use of delivery services by skilled providers that favours women who are wealthier (the concentration curve lies below the line of equality). When the value of the concentration index is zero, there are no wealth related inequalities in the use of delivery services by skilled providers. The concentration curve overlaps with the 45-degree line. From individual level data, the concentration index can be computed using the following formula [18]: Where hi is the health variable of interest (delivery by skilled health providers); μ is the mean of hi; Ri is the fractional rank of individual i in the distribution of socio-economic position; and (; i = 1 for the poorest and i = n for the richest). Wagstaff et al. [19] demonstrated that the concentration index of a health variable is additively decomposable to the concentration indices of the determinants of that health variable. In other words, the concentration index of the health variable of interest can be expressed as the sum of the contributions of the various determinants of that variable, together with unexplained residual component. In decomposing the concentration index of delivery by skilled providers, the following steps are pursued: 1. Regressing the health variable against its determinants: Where: yi = 1 if the delivery was conducted by a skilled health provider; xk: a set of exogenous determinants of delivery by trained health provider; βk: coefficient of determinant xk; and εi: random error term. The dependent variable (delivery by skilled health personnel) is a binary variable with values of 1 (delivered by skilled provider) and 0 (otherwise). The linear probability model (LPM) in Equation 2 above has been used in order to satisfy the linearity assumption of the decomposition analysis, although the estimates are inefficient and the probability of delivery by skilled health providers may not fall within the conventional values of 0 ≤ p ≤ 1 and has heteroskedastic errors [20]. However, the estimated probabilities from the LPM model have been constrained within the conventional values and a comparison with a probit model has not shown significant variations between the coefficients of the LPM and the marginal (or average) effects of the probit regression derived using the dprobit Stata command [17]. Furthermore, to adjust for heteroskedasticity, the predicted values from the regression model have been saved and used as weights to run weighted least squares (WLS) using the "aweight" option in Stata [21] 2. Calculating concentration indices for the health variable and for its determinants (and generalized concentration index of the error term): For any linearly additive regression model of the health variable of interest (yi) such as Equation 2 above, the concentration index for y, can be written as: Where: Cy: concentration index of skilled care at birth (i.e. concentration index of yi); : mean value of determinant xk; μ: mean of the outcome variable yi – that is the mean of deliveries by skilled health providers ck: concentration index of determinant xk GCε: residual component that captures wealth-related inequality in skilled care at birth that is not accounted for by systematic variation in determinants across wealth groups. The term in parenthesis in Equation 3 above expresses the impact of each determinant on the probability of delivery by skilled health providers. In other words, it denotes the elasticity (ηk) of the outcome variable (delivery by skilled health providers) with respect to the determinant xk evaluated at the mean value of yi (delivery by skilled health providers). The concentration index of delivery by skilled health providers is thus a weighted sum of the inequality in each of its determinants, with the weights equal to the elasticities of the determinants: Report of the WHO Commission on the Social Determinants of Health revitalized the need for sustained and concerted efforts to achieve health equity through action on the social determinants of health. The Commission's social determinants framework takes a holistic view of inequities in health and health care within and between countries. Inequities in health/healthcare are caused by the unequal distribution of power, income, goods and services nationally and internationally (Figure (Figure1)1) [22]. Commission on Social Determinants of health conceptual framework. The social determinants of health are the circumstances in which people are born, grow up, live, work and age, and the systems put in place to deal with illness. These circumstances are in turn influenced by a wider set of forces: economics, social policies and politics [22]. The social determinants framework suggests that interventions to address health inequities have to be geared towards: 1. The circumstances of daily living, which include: differential exposure to health risks in early life, the social and physical environments and work associated with social stratification; and health care responses. 2. Structural drivers including the nature and degree of social stratification; biases, norms and values within society; global and national economic and social policy; and processes of governance at all levels. As observed in Figure Figure1,1, the health system is an important social determinant of health influenced by and influencing the other social determinants. However, the health system is not the only social determinant of health. The effect of the each of the factors in Figure Figure11 in the genesis and perpetuation of health/health care inequities may vary from one country to another. It is therefore important to try to identify the effect of the various social determinants of health on health outcomes and access to health care in order to design evidence-based interventions and policy instruments. Data from the Namibia Demographic and Health Survey 2006-07 was used for this study. The data is available on the MEASURE DHS website for registered users. In the linear probability model of the determinants of delivery by skilled health providers and the decomposition analysis the following variables have been used: 1. Dependent variable: delivery by skilled health providers, which takes a value of 1 if the delivery has been attended by skilled health providers and a value of zero otherwise. 2. Independent variables: • Region; • Place of residence – urban/rural; • Wealth as computed from the asset indices; • Education of mother in years of schooling completed • Head of household – a dummy where female household assumes a value of one; and • Insurance coverage – a dummy with a value of one if the woman has insurance coverage. In NDHS 2006-07, a representative two-stage probability sample of 10,000 households was selected. The first stage consisted of selection of 500 primary sampling units (PSUs) from a sampling frame of 3,750 PSUs with probability proportional to size; the size being the number of households in the 2001 Population Census. The second stage involved the systematic selection of 20 households in each PSU [14]. The demographic and health surveys do not contain data on household income or consumption expenditure. Instead wealth index is used as a proxy. The wealth index is based on household ownership of consumer goods (such as radio, television); dwelling characteristics; type of drinking water source; toilet facilities and other characteristics related to the household's socio-economic status. The asset indices are constructed using the method of principal component analysis (PCA) [14]. Studies have shown a close relationship between asset ownership and consumption expenditure in developing countries [23] and that household asset is a good indicator of the long-run economic status of households [24] Data was analyzed using STATA 10 statistical software and MS Excel.
N/A