Investigating the effects of maternal health knowledge on child health in long an province , luận văn thạc sĩ

UNIVERSITY OF ECONOMICS
HO CHI MINH CITY
VIETNAM

INSTITUTE OF SOCIAL STUDIES
THEHUGUE
THE NETHERLANDS

VIETNAM- THE NETHERLANDS
PROJECT FOR M.A. ON DEVELOPMENT ECONOMICS

INVESTIGATING THE EFFECTS
OF MATERNAL HEALTH KNOWLEDGE ON CHILD HEALTH
IN LONG AN PROVINCE

A thesis submitted in partial fulfillment of the requirements for the degree of
MASTER OF ARTS IN DEVELOPMENT ECONOMICS

BY
NGUYEN LE HOANG THUY TO QUYEN

BQ a tAO D~JC
VA DAO TAO ;;
TRUONG DH KINH TE TP.HCMl

TIIU VI~N

Academic Supervisor:
DR. NGUYEN VAN PHUC

G( ~t\1HO CHI MINH CITY, JUNE 2007

ACKNOWLEDGEMENT

I would like to thank my supervisor, Dr. Nguyen Van Phuc for his valuable
guidance, comments, advice and encouragement during my completion of this thesis.

Special thanks go to Dr. Nguyen Trong Hoai and Dr. Nguyen Hoang Bao for their
comments from the start of my thesis.

I am grateful for Dr. Arjun Singh Beddi and M.A Truong Dang Thuy for their
valuable comments and advice from the initial ideas of the theme for this thesis.

I also send my gratefulness to my friends Thu, Vy, Quy for their supportive
friendship during my study at the Vietnam - Netherlands Program for M.A in
Development Economics, especially their kind help during the survey as the enumerators.

Many thanks are respectfully sent to my parents and my husband for providing me
with the opportunity to pursue my goals and for their love and affection, which has
motivated me to complete the thesis. Equal gratitude goes out to my relatives in Long An
Province.

And last but not least, I would express my deepest thank to 102 households at Can
Guoc and Can Duoc Districts, Long An Province for their kind support extended to the
enumerators during the survey.

The thesis is impossibly completed without the continuous support and help of the
above people.

i

CERTIFICATION

I certify that the substance of this thesis has not already been submitted for
any degree and is not being current submitted for any other degree.

I certify that to the best of my knowledge any help received in preparing
this thesis, and all sources used, have been acknowledged in this thesis.

NGUYEN LE HOANG THUY TO QUYEN
Date: 30 June, 2007

ii


ABSTRACT

Children care and protection are greatly paid attention because children are the
future of a country. Their health is specially important because it links to development of
adult human capital and then the national economy. Child health determinants have been
studied by many researchers. Higher parental education has been identified as a
significant contributor to the improvement of child health outcomes in many studies.
However, the distinct functions of formal education and general health knowledge have
not been clarified. This paper aims to investigate the effects of maternal health
knowledge on child health based on the survey of 102 households at Can Giuoc and Can
Duoc Districts, Long An Province.
Household production theory is employed as a core theory to build up the child
health model. Other theories including material well-being, public health intervention and
cultural behavioral theories are used to give further explanation on the child health

determinants. Anthropometric indicators of weight-for-age and height-for-age are used as
proxies for child health. The models are regressed separately for the weight-for-age and
height-for-age Z-scores of under five children.
The research results show that: i) maternal schooling years is somehow proyed to
positively impact on child anthropometric outcomes but its effect is crowded out by
maternal health knowledge ii) maternal access to health information through pubic media
is an important contributor to the improvement of child health iii) genetic inheritance is
important but it is inferior to environmental factors such as housing sanitation, health
knowledge. The findings verify the feasibility of improving Vietnamese stature even
under the constraints of limited access to maternal formal education. Three policy
implications for general education are suggested. Firstly, child care attendants are
targeted objects of health knowledge education. Secondly, periodical training courses are
proposed to ensure their acquisition of updated knowledge. Thirdly, prenatal care
knowledge should be emphasized. In addition, the thesis has suggested efficient channels
for health propaganda such as public media, child caretakers club, etc.
iii


TABLE OF CONTENTS
CHAPTER 1: INTRODUCTION................................................................................................................ 1
1.1. PROBLEM STATEMENT ........•..................•..................................••.•.............•.................•••................... 1
1.2. RESEARCH OBJECTIVES ..................•.••...................•..............................••................................••.......... 2
1.2.1. General objectives....................................................................................................................... 2
1.2.2. Specific objectives ....................................................................................................................... 2
1.3. RESEARCH QUESTIONS ..................................................•..•.................................•.................••..•......... 3
1.4. RESEARCH HYPOTHESES •.•..............•..••..•..........•..................••••.............•••....•..................................... 3
1.5. METHODOLOGY .............•...............••.•...............•.....•••...........•.•.............••...•••............................•......•• 3
1.6. RESEARCH SCOPE .........•....... ; ..........•....................•••••..............................••••.....................•••.•...........• 3
1.7. THESIS STRUCTURE •............••......................................•...................................••.•••............................. 4
CHAPTER 2: LITERATURE REVIEW ................................................................................................... 5

2.1. INTRODUCTION .•..................•......................................•.•................•..........................................•........ 5
2.2. DEFINITION .•.•••.•..........•.•.••.....................•................•.•..........................................•............................ 5
2.2.1. Children ...................................................................................................................................... 5
2.2.2. Child health.................................................................................................................................. 6
2.3. CHILDHEALTHMEASUREMENT •.................................................................••.................••................... 7 ,
2.3.1. Mortality rates ............................................................................................................................. 7
2.3.2. Morbidity rates............................................................................................................................. 8
2.3.3. Anthropometry. ........................................................................................................................... 9
2.4. THEORETICAL FRAMEWORK AND EMPIRICAL STUDIES .................•........................•.........................• 14
2.4.1. Household production theory.................................................................................................... 14
2.4.2 The material well-being theory (or nutrition based theory) ....................................................... 17
2.4.3. The public health intervention theory (or technology-based theory) . ....................................... 19
2.4.4. The cultural behavioral theory.................................................................................................. 20
2.5. THEANALYTICALFRAMEWORK ...••.......................•••.......•.................•.....••..•...................................• 22
2.5.1. Empirical model........................................................................................................................ 22
2.5.2 Variables introduction ............................................................................................................... 23
2.6. SUMMARY .........•..............••..••.................................................................•....•.........••.•..................... 25

CHAPTER3: AN OVERVIEW OF CHILD HEALTH IN VIETNAM ................................................ 26

3 .1.
3 .2.
3.3.
3.4.

INTRODUCTION .•.............................•.••.....•....................•.................•..................................••.••........•
BACKGROUND ON CHILD HEALTH POLICIES AND OUTCOMES ..........................••..•.....•.•....................
NUTRITIONAL STATUS OF CHILDREN IN VIETNAM ...•.•.....••.................................................•...•.....•...
SUMMARY .................................•..•.•...............................•....••......••........•.....•...................................

26
26
29
35

CHAPTER 4: EMPIRICAL ANALYSIS OF CHILD HEALTH IN LONG AN PROVINCE ............ 37
4.1. INTRODUCTION ...................•..••....••..•...•....•••.................................................•••..••....•..•..................•. 37
4.2. OVERVIEW OF RESEARCH PLACE •.....•........•.........•...........................•...•...•....•....•.....••....•..••.............. 37
4.3. DATA DESCRIPTION ...•..•................••••....•..•.............................................•........................................ 39
4.3.1. Sampling method and sample size ............................................................................................. 39
4.3.2.Description ofvariables ............................................................................................................. 43
4.3.3.Descrptive statistics ofvariables ................................................................................................ 50
4.4. STRENGTH AND WEAKNESS OF COLLECTED DATA ........................................................................•... 57
4.5. MODEL SPECIFICATION•..................•.••....••.....•..........•..•••.................•...••...•••...••...........•................... 58
4.6. ESTIMATION STRATEGY .......................................................................•.......................•....••............. 60
4.7. ESTIMATION RESULTS ...................................................................................................•.....•............ 61
4.7.1. Multiple regression results ........................................................................................................ 61
4. 7.2.Interpretation of the results ........................................................................................................ 63
4.8. SUMMARY ••••.•.•.•.••.....••••.•..••.••............•.....••••...••.............•••...........................•...•.....•••..........•.......... 66
CHAPTER 5: CONCLUSIONS AND RECOMMENDATIONS ........................................................... 68
5.1. CONCLUSIONS •.••................•..........................•...•.......•••....•......................................••...................... 68
5.2. RECOMMENDATIONS .........................•...•••......••.......................................•..................•......•............. 69

iv


REFERENCES: .......................................................................................................................................... 71
APPENDICES: ........................................................................................................................................... 77
APPENDIX 1: ............................................................................................................................................ 77
APPENDIX 2: ............................................................................................................................................ 82 '

APPENDIX 3: ............................................................................................................................................ 83
APPENDIX 4: ............................................................................................................................................ 85
APPENDIX 5: ............................................................................................................................................ 90

LIST OF BOXES
BOX 2.1: Vietnamese adults: 25 years, gaining 2 em high .......................................................................... 9
BOX 4.1: Child care club at Hoa Thuan 2 Village, Truong Binh, Can Giuoc District .............................. 47
BOX 4.2: A case from Phuoc Hoa Village, Truong Binh, Can Giuoc District ............................................ 66

LIST OF FIGURES
FIGURE 3.1: Underweight by age and gender .......................................................................................... 30 ,
FIGURE 3.2: Stunting by age and gender ................................................................................................. 31
FIGURE 3.3: Wasting by age and gender ..•••.••.••.•••.•.•.•..•..•....................................................................... 32
FIGURE 3.4: Poor child nutrition by ethnicity and residence ................................................................... 33
FIGURE 3.5: Malnutrition rate of under five children by region and residence ....................................... 34
FIGURE 3.6: Poor child nutrition by level of maternal education and residence ..................................... 35
FIGURE 4.1: The distribution ofstunting .................................................................................................. 85
FIGURE 4.2: The distribution of underweight ........................................................................................... 85
FIGURE 4.3: Correlation between stunting and underweight .................................................................... 86
FIGURE 4.4: The distribution of explanatory variable "child weight at birth" ......................................... 86
FIGURE 4.5: The distribution of explanatory variable 'Jather's education" ............................................ 87
FIGURE 4.6: The distribution of explanatory variable "logarithm offather's education" ....................... 87
FIGURE 4.7: The distribution ofexplanatory variable 'Jather's height" .................................................. 88
FIGURE 4.8: The distribution of explanatory variable "mother's education" .......................................... 88
FIGURE 4.9: The distribution of explanatory variable "logarithm of maternal education" ..................... 89
FIGURE 4.10: JB Test of normal distribution of residuals in HFA regression model............••..•............... 94
FIGURE 4.11: JB Test of normal distribution of residuals in WFA regression model ............................... 99

v

LIST OF TABLES
TABLE 2.1: PIHO classification ofpoor nutrition level in the population ................................................. 13
TABLE 3.1: Some basic targets of the national strategy on the health care for 2001-2010 ....................... 27
TABLE 3.2: Total expenditure on health for 1996-2005 ............................................................................ 27
TABLE 3.3: Actual ratio ofbasic child health indicators ........................................................................... 28
TABLE 3.4: Malnutrition rates of under five children in terns ofWFA
in some Southeast Asia nations in 2004 ................................................................................. 29

TABLE 4.1: Administrative units, areas and population in Long An Province .......................................... 38
TABLE 4.2: Major social indicators at Can Giuoc and Can Duoc Districts .............................................. 39
TABLE 4.3: Investigated objects ................................................................................................................. 42
TABLE 4.4: Coding system for flags ........................................................................................................... 44
TABLE 4.5: Education level ofparents ...................................................................................................... 45
TABLE 4.6: Maternal health knowledge ..................................................................................................... 46
TABLE 4.7: Maternal exposure to health knowledge providing media ...................................................... 48
TABLE 4.8: Sanitation condition ................................................................................................................ 49
TABLE 4.9: Child weight at birth ............................................................................................................... 50
TABLE 4.10: Descriptive statistics ofexplanatory variables ..................................................................... 83
TABLE 4.11: Correlations between maternal education and health knowledge ........................................ 83
TABLE 4.12: Prevalence ofstunting by gender, district and age group .................................................... 52
TABLE 4.13: Prevalence of underweight by gender, district and age group ............................................. 54
TABLE 4.14: Stunting, underweight by maternal education ....................................................................... 55
TABLE 4.15: Stunting, underweight by maternal health knowledge .......................................................... 56
TABLE 4.16: Correlations among dependent and independent variables .................................................. 84
TABLE 4.17: Child health model regression, dependent variable: Height-for-age Z-score ...................... 62
TABLE 4.18: Child health model regression, dependent variable: Weight-for-age Z-score ...................... 62
TABLE 4.19: Ramsey Reset Test, HFA regression model........................................................................... 90
TABLE 4.20: White's General Heterocedasticity Test, HFA regression model ......................................... 91
TABLE 4.21: Ramsey Reset Test, WFA regression model .......................................................................... 95

TABLE 4.22: White's General Heterocedasticity Test, WFA regression model ......................................... 96

vi


ACRONYMS

BLUE

Best Linear Unbiased Estimates

CHC

Commune Health Center

CPCC

The Committee for Protection and Care of Children

CRC

Convention on the Rights of the Child

EPI

Expanded Program of Immunization

GSO

General Statistics Office

FAO

Food and Agriculture Organization

HFA

Height-for-Age

HAZ

Height-for-Age Z-score

JB

Jacque-Bera

LBW

Low Birth Weight

LHS

Left Hand Side

MOH

Ministry of Health

NCHS

National Center for Health Statistics

NN

Neonatal

PNN

Post neonatal

OLS

Ordinary Least Square

RHS

Right Hand Side

SD

Standard Deviation

usc

Under five children

UN

United Nations

UNICEF

United Nations Children's Fund

u.s.

United States

VLSS

Vietnam Living Standards Survey

VNHS

Vietnam National Health Survey

VNNS

Vietnam National Nutrition Survey

WB

World Bank
vii


WFA

Weight-for-Age

WAZ

Weight-for-Age Z-score

WHO

World Health Organization

viii


CHAPTER!
INTRODUCTION

The chapter starts with the introduction of research topic and places. Their
selection is rationalized in section 1.1. It then presents research objectives, questions,
hypotheses and methodology in sections 1.2, 1.3, 1.4 and 1.5 respectively. In addition,
research scope is discussed in section 1.6. Finally, the chapter concludes with thesis
structure in section 1. 7
1.1. Problem statement

Under-nutrition is problematic in the world because it causes over a half of all
child deaths (WB, 2006). To survived children, it impacts on their physical development
and leads to underweight (a low weight-for-age), wasting (a low weight- for-height) and
stunting (a low height-for-age). The consequence is their frequent disease, low labor
productivity when becoming adults and therefore negatively impacts on long-term
economic development (Schultz, 2003). In fact, poor nutrition of children 'is an
implication of "perpetuate poverty" (WB, 2006).
Like other low-income countries, under-nutrition in children under five is a key

issue in Vietnam (WHO, 2007). After over a decade of impressive economic growth with
yearly average rate of

around 7% (GSO, 2006)

(I)

and government's efforts m

developing the primary health care system and national public health programs m
Vietnam (UNICEF, 2006), one fourth of the children are still under-nourished in 2005
(UNICEF, 2006). This figure is quite high according to WHO classification of
malnutrition level (WHO, 1995). Moreover, it is still far away from what the other
countries in the region have achieved. For instance, under-nourished rates in China,
Malaysia and Mongolia are 8%, 11% and 13% respectively (UNICEF, 2006)
Child is under-nourished not only because of having too little food to eat (WB,
2006). Inappropriate child care practices and shortage of health knowledge are also
critical chains of undernourished causes (Maire and Delpeuch, 2005). In addition, it's
implicated by the cultural behavioral theory that children nutritional benefit may not be
(I)

Growth rate of GDP of some ASIAN countries, />
1


maximized if their mothers are not empowered with health knowledge. Evidence is
recently accumulated that an increase in female's education accounts for 43% decline in
child under-nutrition while food security only contributes to 26.1% of child undernutrition reduction (Watson, 2006).
Education is one of the channels to provide mothers with health knowledge
through which child health is improved (Glewwe, 1998). However, other channeJs are

also important to raise maternal health knowledge. It is obvious that health knowledge
can be achieved through maternal accessing to health related information sources such as
watching television, listening to the radio, reading newspapers and magazines, etc. It's
worth for policy implications to examine the effect of the latter on child health
improvement.
This paper aims at examining the effects of maternal health knowledge
perceived from various channels as mentioned above on child health at Can Giuoc
and Can Duoc Districts, Long An Province

It's hoped that the findings of this research are useful for the local government and
key health decision makers at local and international agencies in planning and setting
priorities for education strategies to improve child health at Can Giuoc and Can Duoc
Districts, Long An Province in particular and child health in Vietnam in general.
1.2. Research objectives
1.2.1. General objective

The general objective of the paper is to examine the effects of maternal health
knowledge on child health at Can Giuoc and Can Duoc Districts, Long An Province.
1.2.2. Specific objectives

In aiming for the above general objective, the following specific objectives will be
targeted in the research;

+ Measure the effects of maternal schooling years on child health

+ Measure the effects of maternal access to health information on child health
+ Recommend appropriate maternal health knowledge education strategies to improve
child health in Long An Province.
2

1.3. Research questions

Based on the research objectives, the paper will seek for the replies of the
following questions;
(1) Do maternal schooling years affect on the child weight- for- age (WFA) and heightfor- age (HFA)?
(2) Does maternal access to child health information affect on the child weight- for- age
(WFA) and height- for- age (HFA)?
1.4. Research hypotheses

Based on the theories and the empirical studies, it is expected the following results
of the econometric model;
(1) Increase in maternal schooling years leads to increase in the child weight- for- age
(WFA) and height- for- age (HFA)
(2) Maternal access to child health information leads to increase in the child weight- forage (WFA) and height- for- age (HFA)
1.5. Methodology

The research applies both qualitative and quantitative methods to evaluate the
impact of maternal health knowledge on child health. Qualitative analysis provides
certain evidence on the correct selection of input factors, especially maternal attributes
for child health production function. Moreover, regression model is used to defit;te the
contribution level of each factor mentioned above to the improvement of child health so
that appropriate policy can be recommended.
Cross section data which was surveyed by the author in March, 2007 are used for
the research. There are 124 observations of under-five children included in the survey.
1.6. Research scope

Under-five children are the investigated objects of this paper. Their
anthropometric data in terms of weight-for-age and height-for-age are used as proxies for
the health and nutrition measurement. Under-nutrition is studied because Vietnamese

children are more prone to under-nutrition than over-nutrition. Two districts in Long An
Province, namely Can Giuoc and Can Duoc are selected as research places, given the
3


strong desire of local authorities in improving child health. Can Giuoc and Can Du~c

aim

to achieve the goals of 14% and 16% of a low weight-for-age at under-five children in
2003 (GSO, 2006). In addition, the research scope is feasible to the author under the time
and budget constraints.
1.7. Thesis structure

Given the research purpose, the paper is organized into 5 chapters. In addition to
introduction chapter, the rest of the paper consists of 4 chapters with the outline as
follows;
Chapter 2: Literature Review. This chapter starts with the definition of child

health and its measurement. Theoretical frameworks regarding the determinants of child
health and empirical studies are also reviewed in this chapter. Finally, analytical
framework with the inclusion of health production function, analysis model and its
justification is presented.
Chapter 3: An Overview of Child Health in Vietnam. This chapter presents the

background of child health status in Vietnam. In addition, it provides a further discussion
on the child health determinants based on the data ofVNHS 2001-2002.
Chapter 4: Empirical Analysis of Child Health in Long An Province. This chapter

firstly presents background of research place, sampling method and sample size with the

rational selection of research place. Variables description with descriptive statistics as
well as the strength and weakness of collected data are discussed to evaluate their
representativity and reliability. Finally, the econometric model, estimation strategy,
regression results and their interpretation are presented.
Chapter 5: Conclusions and Recommendations. The chapter summarizes the

findings and concludes with some policy recommendations and research limitations.

4


CHAPTER2
LITERATURE REVIEW
2.1. Introduction
The objective of this study is to examine the effects of maternal health knowledge
on child health. Therefore, child health concepts, its measurements and determinants have
to be defined. Firstly, the chapter starts with theoretical definition of several key concepts
used in the research in section 2.2. Secondly, the measures of child health are introduced
in section 2.3. Thirdly, theoretical background and empirical studies of child health
determinants are reviewed in section 2.4. Fourthly, the analytical framework is
introduced in section 2.5. Finally, summary of the literature review in section 2.6
concludes the chapter.
2.2. Definition
2.2.1. Children
According to the Convention on the rights of the child (CRC), child is defined as
the young human beings at the age of 18 and under (UN, 2005). However, child may be
classified according to different age groups or other criteria for specific purposes. For the
purpose of this research, children are limited to infants and pre-primary schoolers
because of the following reasons;
Firstly, under-five children are the cornerstones of care for healthy growth of

children (WHO, 2006). It's during this period that children are at the riskiest of
infections, child morbidity and mortality, mental development and cognitive decrease if
they are under-nutrition(2). In fact, the most rapid development of a child's brain takes
place during the first two years of his/her life. Sufficient and good quality nutrition
during this childhood period will lead to an increase in learning capability and a
probability of success in school and in life because a well-developed brain is not only
genetically but also nutritionally predetermined (Maxwell, 2005).
2

According to the Latin American Research Network Project, the consequences of under-nutrition at preschool
period have been studied by Beaton, et al., 1993; Bhutta, et al., 1999;Bleichrodt and Born 1994; Lozoff and
Wachs, 2000; Pelletier, Frongillo and Habicht 1993; Pelletier, et al., 1995; Rose, Martorell and Rivera 1992;
Wachs 1995

5


The same pattern is repeated with child's height development. The first two years
of life marks the period of the fastest linear growth velocity given good dietary. (Eckhardt
et al., 2005)
In short, children could not have achieved the potential growth if being exposed to
under-nutrition during the first years of their life (WB, 2006).
Secondly, most of the reported statistical indicators of children health in many
countries in the world, including Vietnam are at this age group. Therefore, the selection
of children at this age group for the research will be feasible in terms of acquiring
reference data.
Finally, the growth pattern of children at this age group implicates their key
healthy milestone in the life. Therefore the study will be worth for policy makers in
planning the appropriate intervention to improve child health.

Based on the limitation of child age in this paper, the following section will
discuss child health concept.
2.2.2. Child health

According to the U.S. Committee on Evaluation of Children's Health (2004), child
health is defined as the status of disease or premature mortality absence with the
inclusion of disease prevention and health promotion. It is "the extent to which an
individual child or groups of children are able or enabled to a) develop and realize their
potential; b) satisfy their needs; and c) develop the capacities that allow them to interact
successfully with their biological, physical and social environments" (Children's Health,
the Nation's Wealth: Accessing and Improving Child Health, p.3, 2004). In short, it is the
ability to recognize aspiration, meet needs and adapt to the environment (Starfied, 2004).
The broad definition is translated by the U.S. Committee on Evaluation of Children's
Health into measurable categories such as "health condition", "functioning" and "health
potential". Health condition reflects the childhood physical status. Functioning measures
how health affects child's daily life. Health potential involves child competence, capacity

.

and developmental potential (Children's Health, the Nation's Wealth: Accessing and

6


Improving Child Health, 2004). However, this health definition is quite conceptual. The
following section will discuss how to measure it.
2.3. Child health measurement

Overall, there are three popular indicators used to measure child health e.g.
mortality, morbidity and anthropometry.

2.3.1. Mortality rates

Mortality rates are classified into the subgroups such as neonatal, post-neonatal,
infant, child and under-five child rates. Neonatal mortality (NN) is the probability of
dying within the first month of life. Post-neonatal mortality (PNN) records the probability
of dying from the age of month 1 to month 12 while infant mortality covers the
probability of dying between birth and the age of one. The likelihood of dying between
ages one and five is categorized as child mortality. Under-five mortality includes the
probability of dying between birth and the age of five
The mortality rates for neonates, infants and children under-five are defined as the
number of deaths per 1,000 births in a given period except child and post-neonatal
mortality rates, which are expressed as the number of deaths per 1,000 survivors at the
defined age (Rutstein, 2000).
The classification of mortality rates is worth for providing appropriate health
policies because each sub-group experiences different potential risks of death. For
instance, neonatal mortality is mainly caused by the medical technology and basic health
care while the others are more relied on nutrition, hygiene, healthy caring practice, etc. In
addition, it is easy to identify and record the death. Therefore, the data are available for
research purpose.
However, mortality rate does not fully describe the child health status because it
does not give information on the life quality but only the fact that the child is dead or
alive. The next section will discuss morbidity, which is included as the child health
indicator to reflect the disability or in diseased status.

7


2.3.2. Morbidity rates

According to Indrayan and Satyanarayana (2000), morbidity in children could be in terms

of infectious or chronic diseases, which cause certain uncomfortable state or restriction in
performing the normal activities of life. Murray and Chen (1993) classified it as selfperceived and observed morbidity. Self-perceived morbidity is relied on the reports of the
respondents disregarding the source of their appraisals relating to the health status. On the
contrary, observed morbidity is the records of health status based on the judgments of
trained physicians.
This distinction is much relied on three types of morbidity (a) observable but not
perceivable morbidity such as hypertension (b) perceivable but not observable morbidity
such as pain and (c) observable and perceivable morbidity such as retinopathy.
Data on child morbidity can be collected by the number of children affected, the
number of episodes of sickness, duration of illness and severity of illness. The terms of
prevalence and incidence are frequently used in this case. Prevalence refers to the
existing cases (the presence of morbidity) and incidence refers to the new cases (fresh
occurrence).
Data on child morbidity are calculated on the basis of percent, per thousand or per
million persons at a point or period. However, it is quite demanding in collecting the data
because of various prevalence and incidence of diseases. Moreover, the severity of illness
can vary according to the people's perception and may lead to over-reporting or underreporting the sickness. This explains for the case that less developed countries have
reported lower morbidity rates than developed countries. As a result, it is not easy to
accurately quantify the morbidity as mortality. Therefore, morbidity is not widely u~ed

in

economic analyses. The shortcomings of mortality or morbidity have motivated a popular
tendency of using anthropometry to analyze child health these days. The following
section will be discussed it in details.

8


2.3.3. Anthropometry

Anthropometric indicators are based on physical body measurements. There are
many indicators used for the health of children and adults such as mid-upper arm
circumference; weight-for-age, weight-for-height and height-for-age; skin-folds, body
mass index, head circumference, etc. However, this section only discusses the most
common health measurement used in children that is the body growth indicators (e.g.
weight-for-age, weight-for-height and height-for-age). Such a selection is justified by the
following reasons;
Firstly, it is empirically evidenced that child poor nutrition is one of the most
popular reasons causing child mortality and morbidity in many countries in the world
(Pelletier & Frongillo, 2002). As a result, many studies limited the assessment of child
health (J) as the nutritional status measured by body growth indicators (Block and Webb,
2003)
Secondly, like other low-income countries, the prevailed threat to child physical
development in. Vietnam is poor nutrition, which then challenges the Vietnamese stature

.

disadvantage (Government Decree No.37/CP issued in June, 1996). This becomes a
topical issue in Vietnam
Box 2.1 PhD. Doctor Tran Thi Minh Hanh, Institute of Nutrition, Ho Chi Minh City
Vietnamese adults: 25 years, gaining 2 centimeters high
Anthropometric data recorded in 1975 showed that the heights of Vietnamese male and female adults
were 160 centimeters and 150 centimeters respectively. In 2000, after 25 years, their average heights
were 162.3 centimeters (male) and 152.3 centimeters (female). It means that the heights of
Vietnamese people have increased just 2 centimeters for 25 years. Comparison was made with the
Japanese and it was found that the Vietnamese men and women were shorter than their Japanese
counterparts at 10 centimeters and 6 centimeters respectively, given the Japanese characteristics of
short stature.
It's time to have the action on how to improve the Vietnamese stature
3

< > For the

rest of this paper, "child health" and "child nutrition" are interchangeably used

9


Finally, the data on child weight/height are frequently recorded by child
caregivers. Therefore, it is inexpensive and relatively easy to collect this type of child
health data during the survey.
Weight-for-height (WFH) measures body weight relative to height. Low WFH in a
child of the same gender and age in the international reference population group is
referred to as "thinness". The severe case of low WFH is referred to as "wasting"
Weight-for-height measures a child's current nutritional status. Wasting indicates a
current under-nutritional status as a consequence of diarrhea, childhood diseases or
insufficient nutrient intake. Wasted children can quickly gain weight after recovering
from diseases with sufficient nutrient intake. Therefore, this indicator can be significantly
used to evaluate the effects of a short-term child health intervention program, which is
however, not the purpose of this paper. Moreover, wasting can mislead the children
health in case of their poor growth in both weight and height. Consequently, child health
status will be over-reported if using this indicator.
Weight-for-age (WFA) measures the body mass relative to age. Low WFA in a
child of the same gender and age in the international reference population group is
referred to as "lightness". The severe deficit in WFA is referred to as "underweight".
WF A is commonly used for monitoring growth and to assess nutritional

change~

over

time. However, this indicator does not distinguish the effects of short-term and long-term
nutritional problem and fails to distinguish between short children of adequate weight and
tall, thin children.
Height-for-age (HFA) reflects a cumulative linear growth measured in the
standing position. Length refers to the measurement in recumbent position, applied for
under- two children. Low HF A in a child of the same gender and age in the reference
population group is referred to as "shortness". The extreme deficit in HFA is referred to
as "stunting". It is caused by the failure to reach genetic potential as a result of interaction
between poor diet and disease. It's also a consequence of poor nutrition before and during
pregnancy, during the first six months, and during the early years of children's lives. In
short, it is a long-term children health indicator for accumulative under-nutrition related
10


to environmental and socio-economic circumstances (WH0,1995;1996). The prevalence
of stunting in the country also reflects its poverty.
Though each of the three above indicators have merits and shortcomings, two of
them e.g. WFA and HFA are selected as proxies for child health used in this paper
because the author aims to examine the effects of maternal health knowledge on the
improvement of the child height and weight, given age and gender.
There are three ways to express anthropometric indices, which are constructed
based on comparisons with a healthy reference population;
Z-score (standard deviation score) is the difference between the measured or
observed value of an individual and the median value of the reference population at the
same age and gender or height, divided by the standard deviation of the reference
population.
Percent of median is ratio of the measured or observed value of an individual to
the median value of the reference population at the same age and gender or height.
Percentile is the rank position of an individual on a given reference distribution,

stated in terms of what percentage of the group the individual equals or exceeds.
Among the three indices, Z-score system is widely used because it is the most
appropriate descriptor of nutritional status for both individual and population-based
applications. Summary statistics such as mean, standard deviation for the population can
be constructed from Z-scores while this cannot be meaningfully done with percentiles.
Percent of median also has certain disadvantage. For instance, it does not show where the
position of the individual in the distribution is. As a result many health and nutrition
centers are gradually switching to the use of Z-score health indicators (WHO, 2000).
The paper selected Z-scores and used the U.S. National Center for Health
Statistics (NCHS)/WHO reference data, which is the most commonly used and
recommended by the WHO.
There have been many debates on the inappropriate application of NCHS
population standard for children in developing countries in recent years with certain
evidences on the ethnic differences between groups or genetic differences between
11


individuals. However, these differences, according to the report of a WHO working
group (1986a) are not large enough to confound the general use of NCHS population
standard because it's scientifically proved that infants and children up to the age qf five
from different geographical regions of the world experience very similar growth patterns
when their health and nutrition needs are met (WHO, 2006). In addition, the development
of statistica1ly valid national reference values is costly. Moreover, these standards are
widely recognized and applied by health agencies in Vietnam because no local standard
is available.
In conclusion, the above justifications render the use of weight-for-age and heightfor-age Z-scores in this paper. They are calculated as follows;
Height-for-age Z-score

z - score == H.-H
l

r

SDr
Where:

Hi is the height of child i
Hr is the median height of healthy children at the same age and
gender from international reference population
SDr is standard deviation of child height at the same age and gender
from the international reference population

Weight-for-age Z-score

z

-score=

W-Wr
l

SDr
Where:

wi is the weight of child i
Wr is the median weight of healthy children at the same age and
gender from international reference population
SDr is standard deviation of child weight at the same age and gender
from the international reference population

12


The most universal cut-off point used for all indicators to define abnormal
anthropometry is -2 Z-score. For example, stunted children are those under five years old
whose height for age, given the gender is less than minus two standards deviations from
the median for the international reference population at ages 0-60 months. The WHO has
proposed the reference classification of poor nutrition level in the population by Z-scores
in table 2.1 below. However, it also recommends that the child nutritional level should be
locally categorized taking into account its specific nutritional nature of each nation and
region.
Table 2.1 WHO classification of poor nutrition level in the population

%of under-five children, below -2 Z-scores

Poor nutrition levels

WFAandHFA

WFH

Low

<10

<5

Medium

10-19

5-9

High

20-29

10-14

Very high
~30

~

15

Source: WHO, 1995
The terms of malnutrition, under-nutrition and over-nutrition are clearly defined
by WHO (2006). Under-nutrition is the loss of body weight as a result of cumulative
insufficient food intake as opposed to dietary energy requirements. It also reflects the
poor absorption of consumed nutrients. On the contrary, over-nutrition is the overweight
and/or obesity as a result of excess food intake as opposed to dietary energy
requirements. Malnutrition refers to the status of deficiencies or excesses of energy
and/or nutrients intake. Based on this definition, it is found that the term "malnutrition"
does not only refer to under-nutrition as it is frequently used these days but also correctly
uses for over-nutrition.
This paper limits to the evaluation of under-nutrition status of the children.
Therefore, only under-nutrition degrees of Vietnamese children are discussed. They are
categorized into the followings;

13


Degree 1 or moderate under-nutrition (-3 S.D < Z-score < -2S.D)
Degree 2 or severe under-nutrition (-4 S.D < Z-score < -3 S.D)
Degree 3 or very severe under-nutrition (Z-score <-4S.D)
In conclusion, the discussion in section 2.3 provides the general view about the
child health indicators. In addition, it justifies for the use of height-for-age Z-score
(HAZ) and weight-for-age Z-score (WAZ) as proxies for child health. Section 2.4 below
will discuss its determinants.
2.4. Theoretical framework and empirical studies related to determinants of child
health
This section introduces four theories relating to the determinants of child health.
First, household production theory is applied as the core theory to examine the linkages
between maternal health knowledge and child health. This theory and the related
empirical studies are presented in section 2.4.1. The other three theories including
material well-being, public health intervention and cultural behavioral theories are used
to further explain the determinants of child health in sections 2.4.2, 2.4.3 and 2.4.4
respectively.
2.4.1. Household production theory
Household production theory is the center of human capital approach based on
which health related models were constructed.
According to Becker (1965), household is not only seen as a consumer of goods
and services but also a producer of commodities. It's assumed that households maximize
utility derived from the basic commodities it produces under money, time and technology
constraints.
Grossman (1972a, b) developed a model of demand for health based on household
production framework in which health is defined as a durable capital stock. It is assumed
that individuals derive utility from the output yielded by health capital and from the
consumption of other commodities.

These ideas of the health production theory are adapted to construct to the utility
function form of households as follows;
14


(2.1)
Household is assumed to choose the combination of other goods (C) and child
health (H) as inputs for the utility function and it is maximized subject to the constraints
of health production function and budget.
The utility function is assumed to be quasi-concave. Equation (2.1) shows that
household's welfare depends on consumption of other goods (C) and child health (Hi).
The relative preferences among the commodities are affected by observed characteristics
such as household characteristics (Xh) and maternal characteristics (Xm). Child health
production function is assumed as follows;
Hi =f(Xh Xc, Xh, Xm)

(2.2)

Child health output depends on inputs including child characteristics, community

...

characteristics, household health and nutritional inputs.
Household's choice in order to maximize its utility function is limited by the
budget constraint (Ih)· In this frame-work, the function related to child health production,
our interest for this research is represented by the following reduced-form equation.

H =f(Xi. Xc, Xh, lh, Xm)

(2.3)

Equation (2.3) shows that child characteristics (Xi) is one of the determinants of
child health. They include all of child attributes such as gender, age, etc and the genetic
factors endowed with child health.
Regarding age, Glewwe (1998) empirically evidences that child health varies with
age. The pattern is that child health decreases in the first two years of age, then levels off
and even increases. The studies of Handa (1999), Christiaensen and Alderman (2001)
confirm and expand the pattern. Child health declines until the age of three and then
increases afterwards. The recent findings of Block and Webb (2003), Chen and Li (2006)
are also consistent with the previous studies. The pattern can be easily understood
because smaller children have more probability of being affected by fever, cough,
respiratory diseases and diarrhea. When the age is increased, the immunity will be
developed and the result is better health outcome (Shehzad, 2005).

15


The regression results ofPonce et al. (1998) reveal that Vietnamese children in the
age group of 19-24 months are more prone to health disadvantages. Based on the review
of the child health patterns relative to age found by previous studies, especially the study
of Vietnamese child health, the author realizes that age is an important determinant of
child health outcome.
In relation to gender, the report of WHO (2003) noted that the rates of boy
mortality in the countries like China, India, Pakistan, etc are lower than girl. This may
result in the logic assumption of gender discrimination in the determinants of child
health. The research on Chinese health of Chen and Li (2006) finds the gender effect
against girl. It is rational due to the tradition of son preference in China. This results in
favorable treatment of parents to boy. However, the finding of Kock and Nguyen Bui
Linh (2002) when regressing the model with VLSS 98 data indicates that boy is more
prone to malnourished than girl in Vietnam. This is consistent with the review on child

malnutrition in Ethiopia of Christiaensen and Alderman (200 1), in Indonesia of J3lock
and Webb (2003) and in Pakistan of Shehzad (2005). The finding challenges the
assumption of gender discrimination. The models of Glewwe (1998) based on child
health data from Morocco, Handa (1999) based on data of child health in Jamaica and
Kovsted et al. (2002) based on data of child health in Bissau, the capital of Guinea-Bissau
(West Africa) prove that gender is an insignificant variable in explaining child health and
nutrition. This is further confirmed in the studies on child health of Haughton and
Haughton (1999), Ponce et al. (1998), Desai (2000) using the VLSS 93 data set. The
findings of previous studies on Vietnamese children health can be justified as the effect
of applying family planning policy with the encouragement of having only two children
per couple. As a result, parents tend to treat children equally despite their gender.
Therefore the assumption of gender bias may not be crucial in Vietnam.
It is true that genetic attributes play a key role in determining a child height, an

important indicator of child health. However, it is difficult to observe and the ability of
unobserved child health endowment in the model can lead to biased estimates. It is
proposed by Glewwe (1998) to include parental height and weight as proxies of the
16