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Examining the Wealth Trends in Kombewa, Kenya
A Thesis Submitted in Partial Fulfillment of the Requirements of the Renée Crown University Honors Program at
Syracuse University
Alizée McLorg
Candidate for Bachelor of Science Degree and Renée Crown University Honors
Spring 2020
Honors Thesis in Public Health
Thesis Project Advisor: Dr. David Larsen, Associate Professor of Public Health
Thesis Project Reader: Dr. Bhavneet Walia, Assistant Professor of Public Health
Honors Director: Dr. Danielle Smith, Director of Renée Crown Honors Program
Date: 4/19/2019
Abstract
The primary purpose of this study is to understand wealth trends in a rural Kenyan community. Understanding wealth trends is important for understanding health outcomes, overall well-being and for informing economic and health policy. Using the Kombewa Health and Demographic Surveillance System, 20,370 households were assessed between 2011-2018. Data on household materials, assets, education and mortality were used. Three indices were developed to quantify wealth: principal component analysis, multiple correspondence analysis and the multidimensional poverty index. Wealth quintiles and levels of deprivation relating to socioeconomic status were then created and analyzed over time. The first two indices demonstrate an increase in wealth during the assessment period with the percentage of households in the wealthiest quintile increasing from 19% to 23%. The multidimensional poverty index, however, shows no change in socioeconomic status over time. Among other factors, lack of sanitation and improved water seems to be the main justification. Our results indicate that households are accumulating assets, but their increased accumulation is not translating to changes in living conditions known to improve health. Hence, while houses are getting wealthier, they are not necessarily getting healthier.
Keywords: Health and Demographic Surveillance System (HDSS), Kenya, low and middle income countries (LMIC), multidimensional poverty index (MPI), multiple correspondence analysis (MCA), principal component analysis (PCA), socioeconomic status (SES), wealth index
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Executive Summary
Measuring wealth is essential for understanding the success of a community and to
predict health outcomes. Socioeconomic status (SES), defined by the American Psychological
Association (APA, 2007) is the social standing of an individual or group. Examinations of SES
often reveals inequities of access to resources and correlated health outcomes. Although in high
income countries, income is a common measurement of SES, many low and middle income
countries (LMIC) do not have data on household income. Therefore, several methods for
measuring SES in LMIC were developed, including asset-based wealth indices.
Using the Kombewa Health and Demographic Surveillance System, three wealth indices
were created to examine wealth and SES trends. The Kombewa HDSS is situated in rural
Western Kenya and has been collecting demographic data since 2011. Our analysis included
households that had at least two available housing characteristic data points. A total of 20,370
households between 2011-2018 were included. Two wealth indices and one SES index were
created using the HDSS: principal component analysis (PCA), multiple correspondence analysis
(MCA) and multidimensional poverty index (MPI). PCA and MCA only used housing
characteristic data and measured wealth while the MPI also incorporated education and mortality
to measure multidimensional wealth or SES.
After examining the change in quintiles over time, PCA and MCA indices demonstrated a
slight increase in wealth. During the first time period, 22% of households were in the poorest
quintile. In the last time period, only 16% of households were in the poorest quintile. PCA and
MCA ranked most of the households in the same quintile with a correlation coefficient of 0.971.
However, MPI results demonstrated that the SES of households did not change over time. About
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70% of households were considered non-deprived for all time periods. Deprivations in education
and mortality remained stagnant while access to sanitation and water decreased over time.
Our results suggest that although asset accumulation and improved housing material has
increased over time, sanitation and water decreased. The decrease in sanitation may be attributed
to lack of coordination among organizations responsible for the water in Kombewa. Sanitation
and water access are associated with health outcomes so while houses are getting wealthier, they
many not necessarily be getting healthier. These changes must come from more comprehensive
policy approaches because improved well-being and health of the community is co-dependent on
the government and household decision-making.
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Table of Contents
Contents
Abstract..............................................................................................................................2
Executive Summary...........................................................................................................3
Table of Contents...............................................................................................................5
Acknowledgements............................................................................................................6
Chapter 1: Introduction....................................................................................................7
Introduction....................................................................................................................7
Literature Review..........................................................................................................8Creation of Wealth Indices:..........................................................................................9Principal Component Analysis (PCA):......................................................................11Multiple Correspondence Analysis (MCA):..............................................................11Multidimensional Poverty Index:...............................................................................12
Chapter 2: Methods.........................................................................................................14
Methods.........................................................................................................................14Study design...............................................................................................................14Setting.........................................................................................................................14Participants.................................................................................................................15Variables.....................................................................................................................15Data sources...............................................................................................................15Statistical methods......................................................................................................16Bias.............................................................................................................................18
Chapter 3: Results and Discussion.................................................................................19
Results...........................................................................................................................19PCA and MCA...........................................................................................................19MPI.............................................................................................................................20
Discussion......................................................................................................................20Key results..................................................................................................................20Interpretation..............................................................................................................21Conclusion..................................................................................................................22
Reference List...................................................................................................................23
Appendices........................................................................................................................26
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Acknowledgements
This thesis would not be possible without the support of several people. First, thank you
to Naomi Shanguhyia for supporting my project, for being excited with me and for connecting
me with her friend Gladys, who made Kenya feel a bit more like home. Thank you to the entire
HDSS team, Winnie Al-Abdneger, Ken Omolo and Peter Sifuna, for welcoming me to Kombewa
and always taking time to explain. Their support and friendship made this thesis possible. Thank
you to Dr. Andrea Shaw, for supervising and supporting my experience in Kenya and for her
continued mentorship. Thank you to my reader, Dr. Bhavneet Walia, who helped contextualize
this project and helped me better understand and develop an interest in health economics. Thank
you to my parents, who supported my ambitious ideas, for listening to me and for always being
there; I am beyond lucky to have them. Finally, thank you to my advisor, Dr. David Larsen, who
helped me reflect on how to make this thesis meaningful at every step. His guidance helped me
build genuine relationships, further develop my interest in global health and develop tangible
research skills. His mentoring has been substantial to my academic and professional growth and I
feel very fortunate to have had his support. Thank you all for your time and effort in helping me
complete this project.
A special thanks to the Renée Crown Honors Program for financially supporting this project
through the Crown-Wise Fund.
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Chapter 1: Introduction Introduction
An estimated 736 million people lived in extreme poverty in 2015, with over half of them
living in sub-Saharan Africa (United Nations, 2019; World Bank, 2019). Poverty decreases
access to health care, decreases opportunity for educational attainment and increases food
insecurity (Akinboade & Adeyefa, 2018; Ferguson, Bovaird Mph, & Mueller, 2007; Peña &
Bacallao, 2002; Peters et al., 2008). Additionally, living in poor housing conditions associated
with poverty is an exposure to poor health (Tusting et al., 2020). Poverty therefore acts in two
ways by decreasing access to positive health factors and by exposing and increasing risk of poor
health such as infant and child mortality (Phelan, Link, & Tehranifar, 2010; Taylor-Robinson et
al., 2019). When examining global wealth trends, it was found that global wealth increased by
66% from 1995- 2014 (Lange, Wodon, & Carey, 2018). However, global wealth held by low
and middle income countries (LMIC) only grew 5% during the same time period (Lange et al.,
2018). Furthermore, many LMICs have experienced large population growth, thus when
examining wealth trends per capita, many LMICs actually declined. Specifically, Kenya’s total
wealth per capita decreased by 5% between 1995-2014 (Lange et al., 2018). Because poverty
disproportionately affects LMICs, measuring the wealth trends of communities in LMICs is
essential for understanding and improving health outcomes (World Bank, 2000). We used a
longitudinal dataset that provided information on housing materials, assets, education and
mortality to examine the wealth and SES trends in a rural Kenyan community during a seven
year period (2011-2018).
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Literature Review
In an effort to understand the importance of measuring household wealth, and how to do
so in LMIC, substantial literature was reviewed. The following articles examine the importance
of measuring wealth and propose various methodologies for doing so in LMIC settings.
It has been clearly demonstrated that there is a positive relationship between
socioeconomic status (SES) and health outcomes (Bruder, 2002; Feinstein, 1993; Haacker &
Birungi, 2018; Yoshikawa, Aber, & Beardslee, 2012). This phenomenon is clearly evidenced in
Kenya, which is considered a LMIC. A study conducted in Kenya analyzed the impact of
poverty on childhood disability risk factors (T Mugoya & Mutua, 2015). Secondary data analysis
conducted using Kenyan Demographic Health Survey (DHS) data, specifically analyzed data on
women with children under five years old and the associated children’s data. Logistic regression
analyses were conducted to examine the association between SES and childhood disability
factors and the results demonstrated that urban women from low SES were approximately ten
times more likely to have never received antenatal care. This study demonstrates how poverty
can decrease access to health care and increase risk factors for child disability. The correlation
between SES and health outcomes is prevalent in many LMIC and further emphasizes the
importance of managing the SES of communities in order to influence health outcomes
positively.
Living in poverty serves as an exposing factor for poor health outcomes. Tusting et al.
(2020) suggests that adequate housing is essential to human well-being and positive health. A
cross-sectional analysis of 33 African countries was done to examine the association between
housing conditions and disease among children. The results demonstrated that improved housing
reduced the odds of malaria infection, stunting, diarrhea and anemia by up to 18%. This study
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reveals the close relationship between housing conditions and health and the importance of
implementing improved housing material, water and sanitation to improve health outcomes.
Additionally, more research on the wealth of communities and how it influences public
health is needed to inform better policy changes. Baum (2005) suggests that more concentration
on the dynamics and distribution of wealth is necessary to formulate policies and adequately
address social inequalities. Baum (2005) argues that public health research has been lacking
when examining the impacts of wealth, especially wealth distribution within countries. If more
public health research was devoted to understanding the distribution of wealth within
communities, impactful policies could be implemented in an effort to improve wealth and health
trends.
Creation of Wealth Indices:
In high income countries, SES is often measured by household income, education or
occupation (APA, 2007). In the United States for example, the Census Bureau evaluates total
family income and sets thresholds for poverty based on family size and consumption (Census
Bureau United States, 2019). This metric is standard throughout the United States and gives a
general understanding of the wealth of the population. This standard metric, however, is not
representative in LMIC. Accurate household income is not available because many individuals
work in an informal sector without income taxation, their income varies or they are self-
employed (Rutstein & Johnson, 2004). One common alternative to measurement of income is
measurement of household consumption.
The Global Consumption Database, managed by The World Bank, collects data about
household consumption in sectors of food, housing, energy and is a comprehensive proxy for
household SES (World Bank, 2019). The Theory of the Consumption Function, stated by
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(Friedman, 1957), is that household consumption expenditure is a highly dependable and stable
function of current income, therefore serving as an accurate proxy for income and SES.
Consumption data, when available, is a smooth and less-variable measure of wealth (Deaton &
Zaidi, 2002). However, consumption data is also difficult to measure in LMICs because of the
large number of informal transactions and lack of detailed expenditure accounts(Deaton & Zaidi,
2002). Therefore, a widely acceptable and common method of measuring wealth is an asset-
based index. Asset-based indices are created from household materials and durable assets which
are collected through household surveys (Rutstein & Johnson, 2004). The basis of creating a
wealth index from household characteristics assumes that if a household has more and better
characteristics (including assets), they are wealthier. After collection of the household
characteristics, analyses are performed, and households are divided into wealth quintiles.
Significant research has been conducted to determine the validity and accuracy of using such
proxies as a determinate for wealth and have demonstrated positive results (Howe, Hargreaves,
& Huttly, 2008). Additionally, measuring SES can be done by using an asset-based index in
conjunction with other demographic data such as education and mortality.
The Kombewa Health and Demographic Surveillance System (HDSS) nearly replicates
the household asset index used by the Demographic and Health Survey and therefore collects
data on housing materials, durable assets and other demographics. Because this is the available
data, asset based wealth indices were created to determine the wealth trends of the Kombewa
community and a multidimensional measurement of wealth was used to asses SES. Through the
literature, three common methods of wealth and SES indices were identified: principal
component analysis (PCA), multiple correspondence (MCA) and multidimensional poverty
index (MPI).
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Principal Component Analysis (PCA):
PCA is a very common method used for creating a wealth index and has been used by the
DHS program, UNICEF, The World Bank and more (Rutstein & Johnson, 2004). PCA uses
household material and asset data to rank households into quintiles. Many studies have used
PCA to measure wealth in LMIC and the process has been described in detail by the DHS
Program (Hargreaves et al., 2007; Harttgen & Vollmer, 2013; Nundy et al., 2011; Wittenberg &
Leibbrandt, 2017).
The philosophy of the DHS Wealth Index is that wealth is an unobserved variable where
a household’s relative wealth position is associated with several indicator variables. The
indicator variables are thought to be correlated to a household’s economic status, meaning that a
household that has more indicator variables (assets) is wealthier. The creation of a wealth index
was initiated because income and consumption data are often unavailable or inaccurate in LMIC.
An important distinction about the PCA wealth index is that it is an economic measurement and
not a socioeconomic measurement because it only analyzes assets and doesn’t measure
education, occupation or other measurements of SES. PCA is one of the most common methods
used for creating a wealth index because of its relative simplicity and its direct relationship to
DHS.
Multiple Correspondence Analysis (MCA):
MCA is a statistical method similar to PCA but does not assume the variables are linear
and can use categorical variables (Ezzrari & Verme, 2012). Several studies have determined the
validity of MCA as a measurement of poverty and it is starting to be utilized more (Asselin &
Anh, 2008; Booysen, van der Berg, Burger, Maltitz, & Rand, 2008; Hruschka, Hadley, &
Hackman, 2017).
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A study conducted in Western Kenya used DHS to create wealth indices over time
(Amek et al., 2015). The wealth indices were created by three methods: PCA, polychoric PCA
and MCA. The results concluded that MCA was the best method because the standardized
weights for variables were higher and had the highest variation. MCA was highly and
statistically significant with PCA and placed 93% of the households in the same quintile. This
study is substantial because it created three different wealth indices to understand the strengths
and weaknesses of each measurement and informed our decision to use PCA and MCA as
methods for creating wealth indices. Although it is not used as often, MCA can be an excellent
method of measuring economic status.
Multidimensional Poverty Index:
Unlike PCA and MCA, MPI is a method used to measure SES, as opposed to wealth. The
MPI identifies people’s deprivations based on three equally weighted categories: education,
health and living standards (Alkire,S. & Santos, 2010). The MPI was developed by the Oxford
Poverty and Human Development Initiative to be a comprehensive measurement of SES that
identifies people who are deprived and non-deprived (Alkire,S. & Santos, 2010). The MPI
became a popular method of measuring poverty because economic experts Anand and Sen
declared that “the need for a multidimensional view of poverty and deprivation guides the search
for an adequate indicator of poverty” (Anand & Sen, 1997). This pushed researchers to develop a
more comprehensive way of measuring poverty that included indicators beyond household
assets.
A study conducted in seven areas in sub-Saharan Africa used MPI to measure SES and
relate SES to mortality. For creation of the wealth index, (Coates et al., 2019) modified the MPI
by removing the health indicator and only including education and household assets. They then
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split households into deprivation groups and the results showed a positive association between
SES and mortality (Coates et al., 2019). This study demonstrates the utility of using MPI as a
measure of SES and examines poverty from multiple lenses other than wealth. Although
different from PCA and MCA, MPI can provide novel insights to the overall well-being of
populations.
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Figure 1: Location of Kombewa HDSS area
Chapter 2: MethodsMethodsStudy design
The analysis in this paper is based on household material and asset data collected by the
Kombewa HDSS. We analyzed change in wealth over time.
Setting
The HDSS operates out of the United States Army Medical Research Unit- Kenya, a
research site that collaborates with the Walter Reed Army Institute of Research (WRAIR) and
Kenya Medical Research Institute (KEMRI) (Sifuna et al., 2014). The Kombewa HDSS is
located in rural Western Kenya, in Kisumu County. It covers about 369 km2and stretches along
Lake Victoria, about 40 km west of Kisumu city (Sifuna et al., 2014). The area has a total of 37
sub-locations and 357 villages and the HDSS research site is located at the heart of the HDSS
area.
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Participants
The HDSS monitored over 200,00 individuals from 46,045 households between 2011-
2018. After deleting the households that did not have more than one observation over time,
20,370 households remained, and all analyses were done on these households. We created three
time variables: T1, T2 and T3. Every household in our analysis has data for T1 and T2. During
T3, only 4413 households had available data.
Variables
As our primary outcome, we assessed how wealth changed over time. Specifically, we
looked at the change in proportion of households in quintiles and deprivations over time. As a
secondary outcome we examined SES and how specific assets changed.
Data sources
The Kombewa HDSS was established in 2007 to conduct clinical trials, nested studies
and disease surveillance (Sifuna et al., 2014). From 2008-2010, household structures were
mapped with GPI coordinates and basic demographic data from households was collected in
preparation for survey collection the following year. In 2011, baseline census surveys were
conducted and have been conducted every six months since, including, births, in and out
migration, pregnancy, morbidity and mortality. Demographic information such as education,
marital status and occupation and household characteristic data are collected every two years.
The PCA and MCA wealth indices are based on household characteristics and the MPI is based
on household characteristics as well as educational and mortality data for the Kombewa
population.
The household indicators used in the creation of wealth indices were housing materials
(source of water, type of sanitation, floor material, roof material, wall material, source of
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cooking fuel and electricity) and durable assets (car, motorcycle, bicycle, tin lamp, refrigerator,
television, radio, solar panel, hi fi stereo, electric iron, fan, cellphone, sofa set, table, flash light,
kerosene lamp, kerosene stove and motorboat). Data on livestock was also collected but
collection only started in 2014, therefore livestock was not included in our analyses. Table 1
explains all the indicators used for PCA and MCA. Table 2 details the definitions of improved
and unimproved sources for housing materials. The MPI consists of three main indicators:
health, education and standard of living. We used a modified version of the MPI and only used
child mortality (<18) as opposed to child mortality and nutrition. The Kombewa HDSS does not
collect data on nutrition and therefore was not available. The remaining indicators: education and
standard of living, followed MPI guidelines. Educational deprivations were calculated based on
years of schooling and child attendance in primary education, and standard of living was
calculated using housing characteristic and asset data. Table 3 explains all the MPI indicators
and their respective weights.
Statistical methods
All statistical analyses were conducted using R version 3.5.2, a programming software
used for statistical computing and graphics(R Core Team, 2018) . We used two methods to create
the wealth indices: PCA, MCA and used an MPI to quantify SES.
PCA is an explanatory data analysis tool that reduces the number of variables in a data set
into smaller dimensions and is a common statistical method used to create wealth indices. PCA
first transforms the initial set of n correlated variables into uncorrelated components (Vyas &
Kumaranayake, 2006). Each component is a linear weighted combination of the initial variables.
The weights from the first principal component are used as a dependent variable and a wealth
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score is calculated for each household to indicate wealth status (Vyas & Kumaranayake, 2006).
The PCA index score for household i is the linear combination:
Equation 1: y i=α 1 ( x1−x1 )
s1+
α 2 ( x2−x2 )s2
+⋯+α k ( xk−xk )
sk
where, xk and skare the mean and standard deviation of asset xk. α kis the weight assigned to each
asset, which remains the same for every household (Córdova, 2008).
MCA is also an explanatory data analysis tool that builds a matrix of uncorrelated linear
combinations to enhance the divergence in the original variables (Ezzrari & Verme, 2012). It can
also be used for qualitative variables, categorical variables and imposes less constraints on the
data (Engels et al., 2014). MCA gives more weight to indicators with smaller frequency and has
been shown to be more sensitive to deprivations than PCA (Ezzrari & Verme, 2012). The MCA
index score for household i is:
Equation 2: Zi=Ri1W 1+Ri2
W 2+…+R ijW j
where, Ri j is the response of household i to an asset j and W j is the MCA weight assigned to each
asset, which remains the same for every household (Ezzrari & Verme, 2012).
MPI is a measurement of SES instead of wealth and uses deprivation cutoffs to indicate
poverty. An n x d matrix, where n is the number of households and d is the number of
deprivations, is used. There are three main dimensions of poverty that are all equally weighted:
health, education and standard of living (Alkire,S. & Santos, 2010). Within the three categories,
there are typically ten indicators and a person is identified as multidimensionally poor if the sum
of all deprivations is 33% or greater (Alkire,S. & Santos, 2010). Because nutrition data was
missing from the HDSS, our analysis had a total of nine indicators. Each household is classified
as multidimensionally poor or non- poor based on their weighted total. This is represented by the
equation:
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Equation 3: C i=∑j=1
d=9
w j
where C i is the weighted score for household i, j is the first indicator and d is the 9th indicator. w j
represents the weight that is applied to each indicator j. Then, each household i is given a
poverty score, pk.
Equation 4: pk=1 if C i≥ 33 %pk=0 if C i<33 %
Bias
In these analyses, a large portion of data is missing. All 46,045 households collect
demographic data every year and collect household characteristic data every two years.
However, the inconsistency of household characteristic data collection resulted in missing data
and only 20,370 households were available to use for analyses. Additionally, because no
households had data for every year between 2011-2018, time frames (T1, T2 and T3) were
created. Altering the number of households and the time variable are potential biases in this
analysis.
Additionally, one potential bias for the MPI is the lack of nutrition data. The original MPI
guidelines include child mortality and nutrition as indicators for the health deprivation. Because
nutrition data was unavailable for the Kombewa HDSS, our health deprivation just included
child mortality. The child mortality indicator was weighted at 33.4% and a household is
considered multidimensionally poor at 33 %. Therefore, any household with a deprivation in the
health dimension will automatically be classified as multidimensionally poor, which can be a
potential bias.
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Chapter 3: Results and DiscussionResultsPCA and MCA
Table 4 shows the proportion of households owning particular asset items between the
three time periods: T1, T2, T3 as well as their PCA and MCA weights. During T1 and T2,
20,370 households were included and in T3, 4,413 households were included. The results show
that wealth increased over time.
PCA assigned the highest weight to owning a television followed by having improved
floor material and having electricity. It assigned the lowest weight to owning a motorboat, tin
lamp and table. MCA assigned the highest weight to owning a refrigerator followed by owning a
car and fan and the lowest weight to having an unimproved roof, owning no cellphone and no
radio. Generally, assets with higher weights represent higher wealth. The weights assigned by
PCA were greater than the weights assigned by MCA for every asset. Despite these differences,
the household wealth scores for PCA and MCA were highly and statistically significant (r =
0.956, p < .01). Additionally, PCA and MCA quintiles were highly and statistically significant
(r=0.971, p<.01) with a kappa statistic of .863.
Both PCA and MCA demonstrate a slight increase of wealth over time. Notable
improvements include wall material, electricity and ownership of a cellphone. In T1, both indices
classified 22% of households in the first quintile and then decreased to 16% in T3. Similarly,
approximately 19% of households in T1 were classified in the fifth quintile and increased to
approximately 23% in T3. Table 5 and Table 6 detail the change in quintile over time for PCA
and MCA respectively. Figure 2 and Figure 3 represent the change in quintile in a stacked bar
plot. The poorest and wealthiest quintiles changed most drastically, and the third quintile
changed the least over time.
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Further examination of the housing materials showed that roof, floor and wall material
and access to electricity increased substantially over time. However, cooking fuel remained
stagnant and sanitation and water decreased significantly. Figure 4 represents the change in
housing material over time.
MPI
Although PCA and MCA scores demonstrated a total increase of wealth, MPI results
indicated that multidimensional wealth, or SES, is staying constant over time. In all time periods,
MPI indicated that approximately 63% of households were non-deprived and 37% were
deprived. Table 7 shows the proportion of households and their deprivations for specific
indicators between the three time periods. During T1 and T2, 20,336 households were included
and during T3, 4,409 were included. Electricity, housing and assets increased while education,
mortality, and cooking fuel did not change over time. However, access to improved sanitation
and water decreased. During T1, 36.5% of households were deprived in water access and
increased to 48.5 % of households during T3. Similarly, 97.7% of households were deprived in
sanitation during T1 and increased to 99.3% during T3. Table 8 details the change in deprivation
over time and Figure 5 represents the change in a stacked bar plot.
DiscussionKey results
Our study, using longitudinal household survey data, suggests that wealth slightly
increased over time in Kombewa, Kenya. However, SES, demonstrated by the MPI, remained
constant over time. The MPI differs from PCA and MCA in its measurement of SES and its
assignment of weights. Individual assets are categorized into one indicator and housing materials
are also categorized into one indicator. However, sanitation and water are their own indicators
meaning they hold more weight in relation to other indicators when compared with PCA and
20
MCA. Because of the larger weighting and the significant decrease in water accessibility, the
MPI is a representation of the decrease in sanitation over time. The results suggest that
ownership of most assets and improved housing material increased, but necessary structural
changes to water source and sanitation decreased. Hence, while households are getting wealthier,
they are not necessarily getting healthier.
Interpretation
The increase in assets such as electricity, refrigerator and cellphone is consistent with
other rural sub-Saharan African communities and suggests that wealth is increasing (Kabudula et
al., 2017). The increase of assets can build capacity for obtaining future assets and increasing
wealth (Chowa, Masa, & Sherraden, 2012). Additionally, the GDP of Kenya increased by
approximately 60% during the time period, indicating that the increase in wealth in Kombewa is
consistent with the trends of the country(The World Bank, 2019). Furthermore, the improvement
of housing material is linked with increased wealth. Finished housing material is associated with
positive health outcomes and improved SES so these improvements indicate that Kombewa is
heading in a positive direction (Morakinyo, Balogun, & Fagbamigbe, 2018; Tusting et al., 2020).
The Kombewa housing trends are consistent with other rural African communities (Tusting et
al., 2019).
Although wealth and SES in the form of housing material has improved, the decrease in
improved water source and toilet type indicates that structural change in sanitation needs to be
made. Although the new Kenyan constitution, created in 2010, assigned responsibility of water
and sanitation to county governments, local authorities have limited resources to implement
change and create sustainable water solutions. An analysis of the implementation of water in
Kisumu County showed that urban parts of Kisumu were given financial resources for water pipe
21
implementation, yet rural areas received no financial assistance (Karan Charles, Nyonje, Leonard
Ogweno, & Peter Anyang Nyongo, 2019). This could be a possible explanation for the decrease
in improved water source in Kombewa and demonstrates that Kisumu county needs to improve
resource allocation to its rural communities. In 2009, it was shown that only 58% of rural water
sources were functional(AMCOW Country Status Overview, 2011). This was also demonstrated
in the WHO report on sanitation where rural households increased their usage of unimproved
sanitation sources (WHO & UNICEF, 2017). These findings indicate that Kombewa is consistent
with other rural African communities but should indicate to governments and households that
improvements to water and sanitation are needed to increase SES and improve health outcomes.
Conclusion
The overall increase in wealth is a positive indication of the well-being of the households
in Kombewa. After creating three wealth indices: PCA, MCA and MPI, we concluded that
ownership of assets and improved housing materials increased. The PCA and MCA indices show
that the proportion of households in wealthier quintiles were greater in T3 than T1, indicating
that wealth increased slightly over time. The MPI, however, shows that SES did not change over
time. This can be explained by the decrease of access to improved sources of sanitation and
water. More structural changes need to be implemented to fully increase the SES, well-being and
health of the Kombewa community.
22
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Appendices
Table 1: PCA and MCA indicators and descriptions
Indicator DescriptionSource of drinking water Improved / Non-improvedType of toilet facility Improved / Non-improvedFloor material Improved/ Non-improvedRoof material Improved/ Non-improvedWall material Improved/ Non-improvedType of cooking fuel Improved/ Non-improvedElectricity Yes /NoMotorcycle Yes /NoBicycle Yes /NoTin lamp Yes /NoRefrigerator Yes /NoTelevision Yes /NoRadio Yes /NoSolar Panel Yes /NoHi Fi Stereo Yes /NoElectric Iron Yes /NoFan Yes /NoCell phone Yes /NoSofa Yes /NoTable Yes /NoFlashlight Yes /NoKerosene lamp Yes /NoKerosene stove Yes /NoMotorboat Yes /No
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Table 2: Definitions of improved and unimproved housing characteristics
Indicator Improved Non- improvedSource of drinking water Buying taps
Piped into compoundPiped to neighborsPiped at water kioskPublic tapBorehole River / streamProtected spring water
Buying tanksPublic well Unprotected wellUnprotected spring waterRainwaterTanker truckBuying water from river/ streamPond/ lake
Type of toilet facility Flush toilet (own and shared)VIP latrine (own and shared)Flush trench
Pit latrine (own and shared)No facility / bush
Floor material Wood planksPolished wood / vinyl / tilesCement
Mud / dung/ sand
Roof material Metal sheet/ tinIron sheet Tiles
Grass / thatchPlastic sheetCardboard sheetWood / timber
Wall material Wood / timberIron sheetCement mudTin/ metal sheet
MudObservation bricksCardboards sheetsCarton / plastics
Type of cooking fuel GasElectricity
Kerosene/ ParaffinCharcoalFirewoodAnimal wasteCrop residue / saw dust
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Dimensions of Poverty
Indicator Household is deprived if: Relative Weight
Education Years of schooling No household member aged 10 years or older has completed six year of schooling
16.7%
School attendance Any school aged- child is not attending school up to the age at which he/she would complete class 8.
16.7%
Health Child mortality Any child (less than 18) has died in the family
33.4 %
Standard of Living
Cooking fuel The household uses unimproved source 5.6%Sanitation The household uses unimproved source 5.6%Drinking water The household uses unimproved source 5.6%Electricity The household has no electricity 5.6%Housing Housing materials for at least one roof,
walls or floor are unimproved5.6%
Assets The household does not own more than one of these assets: radio, TV, telephone, bicycle, motorbike or refrigerator AND does not own a car
5.6%
Table 3: MPI indicators, descriptions and respective weights
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Table 4: Proportion of Assets and Respective PCA and MCA Weights Over Time
Assets Categories Percentage Of Assets Owned Weights
T1(n = 20370)
T2 (n = 20370)
T3 (n = 4413) PCA Index MCA Index
Source of drinking water
Improved drinking water
63.5 56.4 51.6 0.120.00005058
Unimproved drinking water
36.5 43.6 48.4 -0.0000732
Toilet facility Improved toilet 3.4 0.6 0.7 0.25 0.00089Unimproved toilet 96.6 99.4 99.3 -0.00001706
Floor material Improved floor 32.1 46.2 51.9 0.58 0.0003435Unimproved floor 67.9 53.8 48.1 -0.0002329
Roof material Improved roof 83.4 93.6 96.7 0.27 0.0000456Unimproved roof 16.6 6.4 3.3 -0.0003809
Wall material Improved wall 18.3 29.0 34.0 0.32 0.0002717Unimproved wall 81.7 71.0 66.0 -0.00008893
- - -
Cooking fuel Improved cooking fuel
0.8 0.8 0.7 0.31 0.001674
Unimproved cooking fuel
99.2 99.2 99.3 -0.00001361
- - -Electricity Owns electricity 6.4 13.1 17.6 0.61 0.0008788
No electricity 93.6 86.9 82.4 -0.0001034- - -
Car Owns car 1.1 1.0 1.4 0.40 0.001864No car 98.9 99.0 98.6 -0.0000209
- - -Motorcycle Owns motorcycle 2.1 2.7 3.0 0.26 0.0007862
No motorcycle 97.9 97.3 97.0 -0.0000199- - -
Bicycle Owns bicycle 28.9 13.6 10.8 0.25 0.0002383No bicycle 71.1 86.4 89.2 -0.00006047
- - -Tin lamp Owns tin lamp 3.5 78.9 82.8 < 0.1 -0.00003722
No tin lamp 96.5 21.1 17.2 0.00003075- - -
Refrigerator Owns refrigerator 1.2 1.2 1.8 0.49 0.002116No refrigerator 98.8 98.8 98.2 -0.0000273
- - -
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Television Owns television 11.0 12.4 14.6 0.67 0.0008949No television 89.0 87.6 85.4 -0.0001217
- - -Radio Owns radio 70.2 72.9 74.5 0.42 0.0001275
No radio 29.8 27.1 25.5 -0.0003255- - -
Solar panel Owns solar panel 3.6 20.6 28.6 0.26 0.0003184No solar panel 96.4 79.4 71.4 -0.00005049
- - -Hi fi stereo Owns hi fi stereo 2.8 4.8 6.3 0.36 0.0008657
No hi fi stereo 97.2 95.2 93.7 -0.0000365- - -
Electric iron Owns electric iron 2.5 3.4 3.8 0.56 0.001568No electric iron 97.5 96.6 96.2 -0.00004889
- - -Fan Owns fan 0.8 0.7 1.8 0.35 0.001829
No fan 99.2 99.3 98.2 -0.00001594- - -
Cellphone Owns cellphone 69.1 82.7 81.6 0.39 0.0001063No cellphone 30.9 17.3 18.4 -0.000345
- - -Sofa Owns sofa 60.3 65.6 78.0 0.42 0.0001516
No sofa 39.7 34.4 22.0 -0.0002741- - -
Table Owns table 96.6 95.4 96.5 0.11 0.00001123No table 3.4 4.6 3.5 -0.0002716
- - -Flashlight Owns flashlight 43.2 28.9 27.8 0.39 0.000256
No flashlight 56.8 71.1 72.2 -0.0001394- - -
Kerosene lamp Owns kerosene lamp 52.6 32.4 20.9 0.37 0.00022001No kerosene lamp 47.4 67.6 79.1 -0.000149
- - -Kerosene stove Owns kerosene stove 28.3 15.3 17.4 0.45 0.0004208
No kerosene stove 71.7 84.7 82.6 -0.0001144- - -
Motorboat Owns motorboat 0.0 0.1 0.3 <0.1 0.00149No motorboat 100.0 99.9 99.7 -0.00000121
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Table 5: PCA Quintile Change
Quintile T1
(n = 20370) T2
(n = 20370) T3
(n = 4413)1 22.1% 18.8% 16.1%2 19.9% 20.6% 17.8%3 19.8% 20.3% 19.9%4 19.1% 20.1% 23.3%5 19.1% 20.2% 22.8%
Table 6: MCA Quintile Change
Quintile T1
(n = 20370) T2
(n = 20370) T3
(n = 4413)1 21.7% 19.2% 16.2%2 21.0% 19.6% 17.0%3 19.6% 20.4% 20.2%4 18.9% 20.4% 22.7%5 18.8% 20.3% 23.9%
Table 7: Percentage of asset deprivations for MPI
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Indicator Categories Percentage of households in deprivation categoryT1
(n = 20336)T2
(n = 20336)T3
(n = 4409)Years of schooling Deprived 20.6 20.6 19.7
Non-deprived 79.4 79.4 80.3
School attendance Deprived 6.3 6.3 8.1Non-deprived 93.7 93.7 91.9
Child mortality Deprived 4.7 4.7 4.5Non-deprived 95.3 95.3 95.5
Cooking fuel Deprived 96.8 97.7 98.0Non-deprived 3.2 2.3 2.0
Sanitation Deprived 97.7 99.6 99.3Non-deprived 2.3 0.4 0.7
Drinking water Deprived 36.5 43.6 48.5Non-deprived 63.5 56.4 51.5
Electricity Deprived 93.6 86.9 82.4Non-deprived 6.4 13.1 17.6
Housing Deprived 84.3 73.3 68.3Non-deprived 15.7 26.7 31.7
Assets Deprived 37.5 31.2 30.4Non-deprived 62.5 68.8 69.6
Table 8: MPI Deprivation over time
Figure 2: Stacked bar plot of PCA quintile change over time
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DeprivationT1
(n=20336)T2
(n=20336)T3
(n=4409)Deprived 63.4% 63.7% 63.0%Non-deprived 36.6% 36.3% 37.0%
Figure 3: Stacked bar plot of MCA quintile change over time
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Figure 4: Housing material change over time
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Figure 5: Stacked bar plot of MPI deprivation change over time
35
36