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1
MICROECONOMETRIC ANALYSIS ON DETERMINANTS OF ANTENATAL CARE IN BANGLADESH: A FINITE MIXTURE
MODELLING APPROACH
Manhal Mohammad Ali†
†Department of Economics, East West University, Plot A/2, main road, Jahurul Islam City, Aftabnagar, Dhaka – 1212, Bangladesh. Email: [email protected]
Abstract
Estimation of health care demand or utilisation depends on the empirical
specification used in the analysis. This paper estimates antenatal care (ANC)
utilization in the case of Bangladesh and studies its determinants using a finite
mixture model (FMM) of count data models. Bangladesh, a developing country but
with poor and limited resources have made improvements in reducing maternal
mortality yet it still has a long way to go towards achieving Millennium
Development Goals 5 (MCG5). Existing literature points that greater utilization of
ANC reduces improves health outcomes and therefore reduces maternal and infant
mortality. Unlike standard specifications of count data models FMM as the ability to
distinguish between different classes of users of ANC. (for example low frequent
users and high frequent users). This estimation method was applied to the
Bangladesh Demographic and Health Survey dataset 2007 and it was found that a
two component FMM based on negative binomial density - 1 provides better fit to
ANC utilization than other standard specifications and variants of FMM. The study
found that population of users are divided into two types or latent classes, one that
makes low use of ANC and another makes regular or frequent uses. Among the
determinants, women’s education, type of residence, wealth status were found to be
significant determinants of ANC demand amongst the classes, with age, husband’s
education and autonomy were found to be significant determinants amongst low
intensity users and regional divisions were found be important predictors amongst
high intensity users. Pertinent proposals for health policies and reforms in the
health care sector of Bangladesh are also presented and discussed.
JEL classification: I10; C50
Keywords health care utilization, count data, finite mixture model, heterogeneity
2
1. INTRODUCTION
The lack of prenatal or antenatal care (ANC) (care given to mothers before or during
birth) can significantly improve the health of both mothers and children (Holian,
1989; Gertler et al. 1993). Lack of such care is commonly associated with premature
delivery, maternal and infant mortality and postnatal complications (Habibov, 2011:
Magadi et al. 2000). This is one area that merits attention in the case of Bangladesh
as the state of maternal health care in terms of its utilisation is very poor. It is
reported that 50% and 21% of pregnant women in Bangladesh make 1 and 4 ANC
visits respectively, against 4 visits recommended by World Health Organization
(NIPORT 2009). The median number of visits was 3.1 in 2007. About 63% of the
pregnant women were not informed about the signs of the pregnancy complications.
Although the utilization of ANC visits in terms of median visits in Bangladesh has
increased over time with a subsequent fall in maternal mortality, utilization still
remains low (Hossain, 2010). As Koblinsky et al. (2008) mentions, although the use
of skilled birth attendants has increased over the last 15 years, it remains less that
20% as of 2007, and utilization remains particularly low for poor, uneducated rural
women. Bangladesh is on its way to achieve Millennium Development Goals 5 (MDG
5) of reducing maternal mortality by three quarters between 1990 and 2015
however the annual rate of decline needs to triple. Given this backdrop, the purpose
of this paper is to study the socioeconomic, demographic and other determinants of
utilization of ANC services in Bangladesh using count models or count data
regressions, and produce some recommendations or policy implications based on
the outcome of the study. Count data models or regressions is appropriate when the
variable of interest is a non – negative integer valued count for example 0, 1, 2 etc.
Examples include number visits to doctor in a given period, number of cigarettes
smoked, number of drugs dispensed etc.
There exits many studies that have looked and studied into the determinants of
ANC in developing countries. Simkhada et al. (2007) provides a systematic review
on the existing literature. The attempt of this paper is to add to the existing
literature by modelling the counts of ANC visits made by ever married women in
Bangladesh using finite mixture model (FMM) analysis or approach. By using this
3
approach this paper attempts to study and evaluate different range of determinants
of ANC use measured in counts of visits made to rage of providers that provide ANC
services to the maternal population, accommodating the possibility that the
population may be divided into distinct groups or classes that have differential
utilization of ANC or maternal health care and therefore different socioeconomic
aspects. FMM and latent class analysis, a closely related area has received increasing
attention in statistics literature primarily because of the number of cases where
such distributions are encountered (for applications see Lindsay, 1995).
Econometric applications of FMM for health care demand or utilization includes Deb
and Trivedi (1997), Deb and Holmes (2000), Deb and Trivedi (2002), Sarma and
Simpson (2006) and recently Singh and Ladusingh (2010).
A common feature of non–negative integer count variables like number of ANC
visits or doctor visits etc is that they contain large proportion of zero observations,
for example those who make no use of health care or make no visits to health care
provider, as well as a long right hand tail of individuals who make heavy use of
health care. Typically count data models or regressions are applied when the
distribution of the dependent variable, in this case ANC visits as a measure or
indicator of its utilization, is skewed. The feature of data or variable exhibiting high
frequency of zero observations is called over–dispersion what are also known as
‘excess–zeros’. Empirical evidence suggests that over–dispersion is a common
feature of health or medical care utilization data (Deb and Trivedi, 1997). Count
variables require estimation by count regression models since ordinary least
squares would produce biased results (Long and Freese, 2006). Aforementioned, the
dependent variable, ANC visits, is the number of visits made to receive ANC or, the
number of times, or counts, when utilization of antenatal health care has occurred.
When there is over–dispersion, the variance of the variable is greater than the mean
and a simple Poisson regression, the classical model for count variables will not be
valid model because of its equi–dispersion property (see Jones, 2011). It is expected
that data will exhibit over–dispersion since the variance of antenatal utilization is
greater than its mean (mean = 2.178, variance = 7.20). Common count data models
that handle over–dispersion include negative binomial regression model, hurdle or
4
two part model and zero inflated models1. The hurdle or two–part specification
makes the distinction between participants and non–participants. The motivation
for this specification comes from the principal–agent theories. It assumes that
participation decision and the positive observations of the count data are generated
by two separate probability functions. In the first stage a standard binary logit or
probit model is used to model participation decision – the hurdle. In the second
stage a standard count data is applied the most common being negative binomial,
allowing for the fact that the count data is truncated at zero.
Among the commonly used models for count data, Deb and Trivedi (1997)
propose the FMM approach as an alternative in the empirical modelling of health
care utilization. In addition to discrete count data, FMM can also be applied to model
continuous data for instance health care expenditures, as done by Deb and Holmes
(2000). The population of users of ANC may be divided into two or more distinct
latent classes of groups that have different levels of utilization. One may be frequent
user and the other an infrequent user group. In addition to over–dispersion, FMM
allows this population heterogeneity which splits the population into different latent
classes having or making different uses of health care. For instance one group can be
relatively healthy implying less use and another group relatively ill implying heavy
use of care. In the context of ANC care use, each individual in an underlying sub–
population differs in terms of socioeconomic and demographic characteristics
resulting in heterogeneity and differential use of ANC, as also discussed by Deb and
Holmes (2000) and d’Uva (2006). The common count models aforementioned does
not allow for such heterogeneity between sub–groups of users. Not only FMM
accommodates heterogeneity, but the model can also serve as an approximation to
any true, but unknown probability density (Deb and Holmes, 2000). There exists a
fair amount of studies that have looked into determinants of utilization or demand
of maternal and/or ANC services in Bangladesh, for instance: Iftekher (2010) and
Kamal (2009). To the best of my knowledge, there exists no previous study to model
ANC utilization using FMM in a developing country including Bangladesh if not also
developed countries, and therefore not taking into account the underlying
unobserved heterogeneity as discussed above. In the case of ANC utilization in
1 See Jones (2011) basic description of these models. A more formal treatment, including its formulation, properties and estimation is provided by Winkelmann (2004) and Cameron and Trivedi (1997)
5
Bangladesh, Iftekher (2010) uses negative binomial and truncated negative
binomial. Fan and Habibov (2009) and Habibov (2011) use zero inflated and
negative binomial models for the case of Tajikistan and Azerbaijan respectively.
Arthur (2012) uses an ordered logistic regression model to study antenatal
utilization in Ghana using Ghana Demographic and Health Survey therefore not
taking into account the problem of over–dispersion. The aim of this paper is to study
the socioeconomic and demographic and other determinants of ANC by
differentiating users in this case married women, by fitting a FMM accounting for
heterogeneity in uses. The findings of the study are to help in formulating
government health care policies and reforms, providing specific suggestions to
increase use of antenatal care thereby reducing maternal and infant mortality.
The remainder of the paper is organized as follows. Section 2 provides
information on data set. Section 3 and 4 provides methodology, estimation methods,
model selection statistics and empirical results. Section 5 finally concludes with
some suggestions for policy making and reforms.
2. DATA
The date set used for this study comes from BDHS 2007. The 2007 BDHS employs a
nationally representative sample that covers the entire population in private
dwelling units in Bangladesh. The survey used the sampling frame from the census
enumeration areas (EAs) with population and household information from the 2001
population census. EAs were used a Primary Sampling Units (PSU) for the survey.
The survey is based on two–stage stratified sample of households. In the first stage
of sampling 361 PSUs were selected, done independently for each stratum (with 22
strata’s obtained by dividing into economic regions) with probability proportional
to PSU size in terms of households. A household listing was carried out in all
selected PSUs. The resulting lists of households were used as the sampling frame for
the selection of households in the second stage using equal probability sampling
technique. In this was around 10,000 households were selected. The survey was
designed to obtain completed interviews of respondents who were ever–married
aged women from 10–49. BDHS is a part of long standing worldwide demographic
6
and health surveys program which is developed to assist developing countries to
collect data on demographic, socioeconomic factors, reproductive, maternal and
child health, nutrition and epidemiology factors like malaria and HIV/AIDS. BDHS
are organized by MEASURE DHS. More information on data, DHS and BDHS can be
accessed at http//:www.measuredhs.com.
The dependent variable of interest, ANC visits is non–negative integer count
variable i.e. y = 0,1,2,3 etc which serves as a measure of frequency of utilization. In
addition to asking women whether they saw anyone to receive ANC, BDHS records
information about the frequency of ANC utilization, which are recorded as counts or
number of visits made. The respondents or women were asked if they saw anyone
for ANC during pregnancy period. The respondent had the opportunity to answer
‘no one’ or ‘someone’. The definition of someone in this question includes a wide
range of ANC providers in Bangladesh such as: MBBS doctors, nurses or midwives,
auxiliary midwives, family welfare visitors and assistants, skilled birth attendants,
health assistants, unqualified doctors and relatives. For the women who did receive
care, BDHS then asks the follow-up question: “How many times did you receive ANC
for this pregnancy?” The responses to this question vary from 1 to 20 visits.
Definitions of determinants or explanatory variables are provided in table 1. This
study uses socioeconomic and demographic determinants that includes age, division
or region, religion (whether Muslim or non-Muslim), wealth index that is given in 5
quintiles: poorest, poorer, middle, richer, richest, education, husband’s education, an
accessibility factor namely whether the respondent lives in rural or urban
household, a measure of women’s status in the household measured autonomy on
own health care and whether the women was or were pregnant with a male child.
Two most recent systematic reviews on the literature found that the above
socioeconomic and demographic factors, pregnancy characteristics, accessibility are
strong determinants of ANC utilization in developing countries (Simkhada et al.
2007; Say and Raine, 2007)
Table 1. Definitions of variables used in regression analysis (n = 10996)
Variables Definition
Dependent variable Antenatal visits Number of antenatal visits during pregnancy
7
Independent variables Age A continuous variable that indicates current age of women in years.
Education A continuous variable that indicates women's education in years.
Muslim A binomial discrete variable. If Muslim = 1, otherwise = 0.
Husband's education A continuous variable that indicates husband's education in years
Rural A binomial discrete variable. If women resides in rural area = 1, otherwise = 0.
Poorest households A binomial discrete variable. If women are from poorest household = 1, otherwise = 0.
Poorer households A binomial discrete variable. If women are from poorer households = 1, otherwise = 0.
Middle income households A binomial discrete variable if women are from middle income households = 1, otherwise = 0.
Richer households A binomial discrete variable. If women are from richer households = 1, otherwise = 0.
Richest Household A binomial discrete variable. If women are from richest households = 1, otherwise = 0.
Barisal A binomial discrete variable. If women resides in Barisal = 1, otherwise = 0.
Chittagong A binomial discrete variable. If women resides in Chittagong = 1, otherwise = 0.
Dhaka A binomial discrete variable. If women resides in Dhaka = 1, otherwise = 0.
Khulna A binomial discrete variable. If women resides in Khulna = 1, otherwise = 0.
Rajshahi A binomial discrete variable. If women resides in Rajshahi = 1, otherwise = 0.
Sylhet A binomial discrete variable. If women resides in Sylhet = 1, otherwise = 0.
Autonomy: Have final say on own health care.
A binomial discrete variable. If women has autonomy on won health care = 1, otherwise = 0.
8
Male A binomial discrete variable. If pregnant with male child = 1, otherwise = 0.
Other important determinants of health care use or demand are insurance related
variables however BDHS 2007 does not contain insurance on such variables hence
they are not part of this study.
3. METHODS
Recent work in health economics has advocated a more a robust and flexible
approach amongst the classes of count data models: the finite mixture approach to
health care utilization. The FMM based on standard count models (Poisson or
negative binomial) allow for modelling of unobserved heterogeneity in a non-
parametric way across individuals, splitting the population into different groups. In
this approach the unobservable heterogeneity is treated as a discrete random
variable where each category of the variable represents an unobservable ‘type’ of
individual (Deb and Trivedi, 1997). For instance in a two-point or component finite
mixture model there would be two types, such as ‘healthy’ and ‘ill’ individuals as
interpreted in Deb and Trivedi (1997) who applies FMM to model health care
utilisation by Medicare beneficiaries in US. These two types are two latent
populations that reflect unobservable differences in frailty across the populations.
In an FMM, the population is assumed to be made up of C distinct populations in
proportions , , , where , , , The C-point
finite mixture model or the density and is given by
where the mixing probabilities are estimated along with all other parameters,
denoted as . Also,
9
The component distribution in a C-point finite mixture negative binomial model
(FMMNB) are specified as
,
,
, , ,
,
,
, ,
where, , , are the latent classes, , exp( ) and , ,
Inserting the value of , in (2) implies
,
,
,
,
,
Equation (2) is also gives the negative binomial density. Of the densities available in
the statistical literature for econometric models of count data, the family of negative
binomial densities is the most flexible. This study looks at two cases where one case
and in another case . The latter corresponds to negative binomial
density – 1 (NB1) and the former corresponds to negative binomial density – 2
(NB2) (Winkelmann, 2004; Cameron and Trivedi, 1997). In addition the study also
uses the Poisson density to estimate and evaluate several FMM’s. Moreover NB1 and
NB2 estimations are also considered for the purpose of model comparison or
selection. Also in this paper we consider FMMs with only two points of support i.e. C
= 2. The results of Deb and Trivedi (1997) suggest that the two-point or two-
component FMM is sufficiently flexible to explain health care counts quite well with
one group as frequent or high users of care and the second group as infrequent or
low users. Estimations of FMM and its variants are carried out using maximum
likelihood using Newton-Rhapson algorithm procedure. For the basis of
comparisons or model selection two information criteria namely Akaike information
criteria (AIC) and Bayesian information criterion (BIC) are used along with log
likelihood. The AIC is given by:
AIC = - 2logL + 2K,
and the BIC by:
BIC = - 2logL + K log (N)
10
where log L denotes the maximized log-likelihood value, K is the number of
parameters in the model and N is the sample size. Models with smaller AIC and BIC,
are preferred. All FMM estimation and count regressions are carried out by
adjusting for sample survey design. BDHS uses a complex multi stage survey design
based on stratification and clustering. Statistical or econometric analysis of surveys
with such a complex design will render the regression results biased unless
estimations are adjusted for the sample survey design namely stratum, clusters, and
sample weights (Levy and Lemeshow, 2008).
4. RESULTS
Table 1 provides summary statistics of variables used in regression analysis. The
mean number of ANC visits made by respondents or women was 2.18 with a
minimum of 0 and maximum of 20 visits. The education variable measures
education of women in years or years in education which has a mean of 4.52 years.
This indicates low level of education attainment and inequality of opportunities in
Bangladesh where 35% of the women reported 0 years of education. About 90% of
the respondents were Muslims and the rest non-Muslims. The educational
attainment of husbands is also very depressing with mean of 5.15 years in education
and with 35% having no education at all. A larger proportion of the sample dwell in
rural areas, 64% of women reported having autonomy on own health care and 53%
of the pregnant women are born with male child.
Table 2. Descriptive statistics of variables
Variables
Dependent variable Mean S.D. Min Max
Antenatal visits 2.18 2.68 0 20
Independent variables Age 30.62 9.33 15 49
Education 4.52 4.40 0 17 Muslim 0.90 0.30 0 1 Rural 0.62 0.48 0 1 Husband's education 5.15 5.00 0 19
11
Poorest households 0.16 0.37 0 1 Poorer households 0.18 0.39 0 1 Middle income households 0.19 0.39 0 1 Richer households 0.20 0.40 0 1 Richest Household 0.27 0.44 0 1 Barisal 0.13 0.34 0 1 Chittagong 0.18 0.34 0 1 Dhaka 0.21 0.41 0 1 Khulna 0.16 0.36 0 1 Rajshahi 0.19 0.29 0 1 Sylhet 0.13 0.34 0 1 Autonomy: Have final say on health 0.64 0.48 0 1 Male 0.533 0.50 0 1
Figure 1 below provides a histogram of the dependent count variable: ANC visits
made by women. As the figure shows a substantial portion of observations (38%)
are reported to have made so visits with only 77% making 3 or less visits, against 4
visits recommended by World Health Organization. Using ordinary least squares
and Poisson regression with its equi-dispersion to model utilization ANC will thus
not be valid as the figure shows presence of over-dispersion.
Figure 1. Histogram of antenatal care visits.
0.1
.2.3
.4
Fra
ction
0 5 10 15 20Antenatal care visits
12
Table 3 provides the model selection statistics. As the table shows, based on
entire sample of study, the log likelihood and both AIC and BIC measures support
FMM with NB1 density with 2 components or classes (FMMNB1 – 2). Based also on
evidence and statistics, Deb and Trivedi (1997) found that FMMNB1 – 2 model as
the best, allowing interpretation of health care utilization to be made in two distinct
components or classes: healthy and ill. Based on statistics and indicators given in
table 3, FMMNB1 – 2 was compared with hurdle two-part NB1 (HNB) model. The
latter model performs better than FMMNB1 – 2 in terms of likelihood, AIC and BIC
measures, however the statistics or indicators don’t significantly or substantially
differ. Moreover, when BIC indicator for FMMNB1 – 2 was adjusted for the sample
size, the indicator is supportive of estimation using FMMNB1 – 2 rather than HNB
specification. In addition because all users of care are represented by one equation
in the two-part HNB model, it does not account for heterogeneity in utilization
between subgroups of users. If users are drawn from distinct groups then HNB will
not be able to adequately present demand or utilization of health care for instance
ANC. Thus in what follows the empirical results on determinants of ANC utilization
is obtained using FMMNB1 – 2. In align with Deb and Trivedi (1997), this allows
interpretation of having the population or users of ANC divided into two
components or classes i.e. one group that make have use of ANC (frequent users)
and another that make low uses (infrequent users)
Table 3. Model selection
Model Log
likelihood AIC BIC
FMM - 2 Negative binomial - 1 (FMMNB1) -8430.78 16935.57 17175.91
FMM - 2 Negative binomial - 2 (FMMNB2) -8471.77 17017.54 17257.88
FMM - 2 Poisson -8526.63 17123.26 17350.61
NB1 -8616.764 17269.53 17386.45
NB2 -8616.76 17269.53 17386.45 FMM - 2 indicates FMM with 2 components
Table 4 presents the parameter estimates and average marginal effects (AME) of the
determinants of ANC using FMMNB1 – 2 for the two components or groups of users
of ANC. Table 4 shows that important number of socioeconomic and demographic
13
covariates or explanatory variable are statistically significant determinants of ANC
utilization or demand, especially for component or group 1. It is apparent that
effects of some of the covariates are different for the two components or sub-groups
of users. The standard count data models cannot uncover such patterns because it
assumes all users come from the same population. The interpretation of at the
bottom of table is that it represents the proportion of observations in classes or
components 1 and 2 which is statistically significant at 1 percent level. From the
table there are about 79% in group 1 and 21% in group 2. These components or
classes are latent so it is helpful to give some interpretation. Table 5 provides the
sample average estimates of the fitted mean and other summary statistics for the
two latent classes or components. Table 5 and the summary statistics make explicit
the implication of the FMM. The first latent class or component categorized as low or
infrequent users comprising of 79% has a relatively low number of ANC visits with a
value of 1.74 visits. The second component categorized as high or frequent users
comprising of 21% has a relatively high number of ANC visits of around 3.5 visits.
The probability weighted average of the two classes is
which is close to the overall sample average of 2.18. The variation of
the second component is relatively greater than the first indicating that there is
some overlap between the two distributions. There also exists substantial variation
or differences from percentile values across the components. Figure 2 provides
histograms of the distributions of the fitted means for the two components, where
one can see that the second component experiences more ANC visits. The parameter
estimates are the over-dispersion parameters where the estimates are
significantly different from zero, reinforcing the stylized fact that medical care
utilization counts are over-dispersed relative to the Poisson model.
From table 4 effects of some of the covariates as measured by AME varies across
the two components or latent classes corresponding to low users and high users
with a statistically significant impact. For low users of ANC, current age although in
magnitude small, is statistically significant determinant of ANC use or demand
where as age increases by one year, antenatal visits decreases by -0.028. Women’s
education given in years of education is statistically significant for both high and low
users suggesting that education makes individuals more knowledgeable about
14
preventive and maternal care leading to higher probability of ANC visits. Amongst
low group an increase in education by one year leads to increase in ANC visits by
0.114 compared to 0.094 for high group users. The effect of religious beliefs is
statistically significant for high group users where being from a Muslim household
leads to lower probability of making ANC visits. The effect of women dwelling in
rural households has a statistically strong significant effect amongst the low users
but a weakly significant effect for high intensity users. This raises accessibility issues
implying that one reason for low utilization of ANC is lack of proper or nearby health
facilities or health care providers in rural areas2. Husband’s or partner’s education
also plays a statistically significant role in utilization ANC amongst the low group of
users but not amongst the higher group. Overall from education variables, lower
education leads to inequalities in opportunities and inequalities regarding
utilization of ANC in Bangladesh. From the wealth quintiles, women’s affordability
perspectives are important predictors of ANC use. Women from richer or richest
households tend to use more ANC than those from lower wealth quintiles. All the
wealth quintiles are statistically significant predictors of ANC visits amongst low
group or low intensity users. Women’s from richest household is a statistically
significant determinant of ANC utilization for both low intensity and high intensity
users, whereas a woman from poorer households is weakly significant determinant
amongst high intensity users. The other wealth category namely middle income
household was dropped along with regional variable Sylhet from the regression
analysis due to perfect multicollinearity. There is presence of regional disparities
regarding the use of ANC however it is statistically insignificant amongst low users
but relationships between regions or divisions and ANC is somewhat significant
amongst high group users: the probability of using ANC is higher and statistically
significant amongst households living in Barisal, Khulna and Rajshahi. Women’s
autonomy is associated with higher probability of use of ANC and is statistically
significant amongst low group but not for high users. Women pregnant with male
child however have no statistical significant effects amongst the latent classes.
2 The latest BDHS dataset, BDHS 2007 does not have supply side covariates like presence and/or distance to health facilities therefore it was not possible to include them in this study.
15
Table 4. Parameter estimates and marginal effects (FMMNB1 – 2)
Component - 1 Component - 2
Low users: average (1.74) High users: average (3.47)
79% 21%
std. error AME std. error AME
Constant 0.462* (0.246)
0.585* (0.343)
Age -0.020*** (0.005) -0.028 0.010 (0.009) 0.030 Education 0.081*** (0.008) 0.114 0.032** (0.015) 0.094 Muslim -0.057 (0.100) -0.081 -0.311** (0.139) -1.025 Rural -0.329*** (0.067) -0.484 -0.235† (0.149) -0.704 Husband's education 0.032*** (0.008) 0.044 0.005 (0.010) 0.015 Poorest households -0.371** (0.127) -0.464 -0.132 (0.125) -0.367 Poorer households -0.230* (0.119) -0.300 -0.234† (0.152) -0.632 Richer households 0.270** (0.117) 0.411 0.085 (0.288) 0.251 Richest Household 0.484*** (0.099) 0.775 0.313* (0.180) 0.988 Barisal -0.234 (0.215) -0.301 0.602** (0.262) 2.201 Chittagong -0.145 (0.203) -0.194 0.481 (0.339) 1.624 Dhaka -0.110 (0.202) -0.149 0.372 (0.308) 1.205 Khulna 0.058 (0.212) 0.083 0.588* (0.331) 2.146 Rajshahi 0.022 (0.202) 0.030 0.801*** (0.244) 3.103 Autonomy: Have final say on health 0.150** (0.064) 0.206 -0.121 (0.118) -0.354 Male
0.020
(0.054)
0.028
0.091
(0.115)
0.264
1.763*** (0.195)
2.29E-06** (9.88E-06)
0.789*** (0.042)
0.211*** (0.042)
Log likelihood -8430.783
N (observations) 4894 *** 1% level significance; ** 5% level significance; *10% level significance
†15% level significance Robust sample adjusted standard errors in parentheses
16
In summary, from results presented in table 4 and 5, FMM has the interpretation
that data are generated by two classes of individuals, first which accounts for 79% of
the population who are relatively low users of ANC visits and the second that
accounts for about 21% of the population who are high users of ANC visits and thus
unobservable characteristics influencing ANC utilization must be take into account.
From table 5, socioeconomic and demographic factors like age, women’s education,
income and rural residency, autonomy and husband’s education are significant
determinants of demand or ANC amongst the low users of ANC. Women’s education,
rural residency and some wealth quintiles are also significant determinants of ANC
utilization amongst high intensity users. Regional factors are important significant
determinants for high intensity users but not for low intensity group. The results
are in line with Grossman’s (1972) theory of human capital where education makes
a person more efficient in the use of services in this case maternal health care
services, leading to more health conscious behaviour thereby leading to improved
maternal health. According to Grossman’s model, higher income also leads to more
utilization of health care and vice-versa and the effect is stronger and robustly
significant amongst low intensity users rather than high intensity users.
Table 5. Distribution of fitted means from finite mixture component densities
Statistic Component
1 Component
2
Mean 1.74 3.47
S.D 1.66 1.71
Minimum 0.23 0.92
Maximum 11.18 14.29
Percentile 10 0.45 1.80
25 0.63 2.28
50 1.11 3.02
75 2.23 4.16
99 7.86 9.24
17
Figure 2 Fitted values distribution, FMMNB1 – 2
5. CONCLUSION
The present study attempts to explore ANC utilization in Bangladesh by FMM in
particular by FMMNB1 – 2 model and finds that population of users are divided into
two distinct latent classes, one being the high group user and another the low user
group which accounts for majority of the population. There is strong support for the
hypothesis of population being divided into two distinct sub-users of ANC, one with
low mean and low variance and another with higher mean and higher variance.
Therefore from the results of the analysis, it is clear that the different latent classes
possess different socioeconomic and demographic characteristics and thus
unobserved characteristics influencing ANC must be taken into account. This should
assist in the preparation of perspective policies for more efficient utilization of
0.2
.4.6
.8
Density
0 5 10predicted mean: component1
0.1
.2.3
.4
Density
0 5 10 15predicted mean: component2
18
resources. Standard count models that assumes all users come from the same
population cannot unravel such heterogeneity.
From the results of the analysis, women’s age, education, rural or types of
residency, wealth or income, husband’s education are significant determinants of
ANC utilization or demand amongst low group users in Bangladesh from the sample
data provided by BDHS. Women’s education and rural residency are also significant
determinants of ANC amongst high group users thus underlying their robustness.
Amongst the wealth quintiles, households from poorer and richest group are
significant determinants of ANC use amongst high group users, albeit weakly
significant for poorer households. Also, women living in certain areas or divisions of
the country are significant predictors of ANC use amongst high intensity users. The
empirical evidence presented in this study has important implications for health
policy in Bangladesh.
Overall the results suggest that to increase utilization, accessibility, and equality
of ANC use and to achieve MDG 5 of reducing maternal mortality, policy makers
need to adopt measures by allowing for more MBBS doctors, doctors on residency
programs or on internships, satellite, community or mobile clinics to operate in
rural areas. Policy makers or government can also allow other programs such NGO
organization, non government and not-for-profit organizations, and state based
funded programs to operate in rural areas to disseminate more knowledge about
maternal and infant health, early warnings or signs of pregnancy complications.
Such health education and health promotion programs should and can address the
issues of ANC in a comprehensive way that encompasses improved information,
education and empowerment of women on the benefits of its usage, since a key
obstacle in ANC utilization is lack of education. Another pertinent and pragmatic
solution is to improve the quality and number of academic educational activities for
instance primary and secondary schools, especially in rural areas as well for non-
academic educational activities like health and family education activities, active
welfare or social community groups etc. Evidence also suggests that poverty and
income are significant determinants of ANC use especially amongst low intensity
users. Hence this warrants a greater budgetary allocation and public expenditure to
improve maternal and infant health, implementation of targeted social assistance
program that delivers benefits to the poorest families, and increasing overall
19
economic activities of the nation to generate higher GDP for instance establishment
of businesses, jobs, trade etc. However such income growth and pro poor policies
needs to be implemented effectively in tandem with policies aimed at resolving
rural/urban regional inequalities in accessing ANC.
Finally, there are certain limitations to this study and scope for extensions. Firstly
the study does not take into account quality and components of ANC, data on its
costs and effectiveness. The study also does not take into account other covariates
like pregnancy and maternal related characteristics, although it has taken into
account whether women was pregnant with male child and women’s autonomy.
Nevertheless the findings of the study taking into account the dichotomy between
low and high intensity users of care will provide impetus and create a baseline in
regards to study and assess the determinants of ANC utilization in Bangladesh and
other developing countries.
Acknowledgements I would like to thank Dr. M Sekander Hayat Khan and three
other anonymous referees for their helpful comments on BDHS dataset. All
remaining errors are mine.
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