Maternal Cognitive Function and Neurobehavioral Development of Underprivileged Children
Conditions: Child Development
Sponsor: University of Dhaka

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COVER PAGE 
 
 
Official Title of the Study : Maternal Cognitive Function and Neurobehavioral    
                          Development of Underprivileged Children 
 
NCT Number 
 
: NCT03321591 
 
Date of the Document 
: 19/09/2016 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Maternal Cognitive Function and Neurobehavioral Development of Underprivileged 
Children 
 
 
Introduction 
Child development consists of several interdependent domains of sensory-motor, 
cognitive-language, and social-emotional function (Grantham-McGregor et al., 2007; Walker 
et al., 2007). Children’s development is affected by psychosocial and biological factors 
through changes in brain structure and function, and behavioral changes (Wachs, 2000).  
Experiences in the first few years of life are of particular importance because vital 
development occurs in all the domains during this period, and the interaction between early 
environments and genetics influences this development and human behavior (Committee on 
Integrating the Science of Early Childhood Development, 2000). The brain growth occurs 
rapidly through neurogenesis, axonal and dendritic proliferation, synaptogenesis, cell death, 
synaptic pruning, myelination, and gliogenesis (Grantham-McGregor et al., 2007). Brain 
development can be modified by the quality of the environment (Grantham-McGregor et al., 
2007). Independent animal research suggests that early under nutrition, iron-deficiency, 
environmental toxins, stress, and poor stimulation and social interaction can affect brain 
structure and function (Black et al., 1998; Liu et al., 2000; Meaney, 2001; Morgan et al., 
2001; Rodier, 2004; Webb et al., 2001; Wilson et al., 2000 ).   In both humans and animals, 
variations in the quality of maternal care, a part of home environment, can yield changes in 
stress reactivity, anxiety (Gunnar, in press), and memory function in the offspring 
(Grantham-McGregor et al., 2007). In later childhood the affected children will subsequently 
have lower levels of cognition and education. It is mentionable that remarkable recovery is 
often possible with early intervention through more nurturing environment with adequate 
stimulation, despite the vulnerability of the brain to early insults (Black et al., 1998; Bredy, 
2003).  
 
It is estimated that over 200 million children under 5 years of age in developing 
countries (low-income and middle-income countries) are not attaining their developmental 
potential, primarily because of poverty and associated health, nutritional deficiencies, and 
unstimulating home environment, and most of them live in south Asia and sub-Saharan 
Africa (Grantham-McGregor et al., 2007; Walker et al., 2007). Stunting, inadequate cognitive 
stimulation, iodine deficiency, and iron deficiency anemia are identified as key risk factors, 
where the need for intervention is urgent, that prevent millions of young children from 
fulfilling their developmental potential (Walker et al., 2007; Walker et al., 2011). In low-
income and middle-income countries, 34% of children younger than 5 years have linear 
growth retardation or stunting (Walker et al., 2011) resulted from poor nutrition often 
accelerated by infectious diseases (Walker et al., 2007). It is reported that patterns of growth 
retardation are identical across countries (Shrimpton et al., 2001). Although the vacillation in 
growth starts in utero or in the first 12-18 months, continue to around 40 months (Martorell et 
al., 1995), but most children having stunting remain stunted through to adulthood (Grantham-
McGregor et al., 2007). On the other hand, poverty and stunting are identified for indicators 

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of poor development because they represent different types of biological and psychosocial 
risks. Poverty is related to inadequate food, and poor sanitation and hygiene that increase 
infections and stunting in children. Poverty is also connected to poor maternal education, 
increased maternal stress and depression (Bradley & Corwyn, 2002; Hamadini & Grantham-
McGregor, 2004; Baker-Henningham et al., 2003), and deficient stimulation in the home 
(Schady & Paxson, 2005). All these factors deleteriously affect child development which, in 
turn, produces poor school achievement, which is further worsened by poor family support 
(Grantham-McGregor et al., 2007). Risk factors associated with poverty frequently happen 
together, and degree of development becomes lower with the number of risks factors (Rutter, 
1989). Deficits in child development are often occurred in infancy (Feinstein, 2003; Espy et 
al., 2001) and increase further with age (Richter et al., 1998; Walker & Grantham-McGregor, 
1990; Lozoff & Teal, 2004). Several longitudinal studies have found substantial association 
between socioeconomic status and parental wealth at birth, and cognitive attainment (Sigman 
et al., 1991; Stein et al., 2005). Poverty and sociocultural background increase children’s 
exposure to psychosocial risks that influence development through behavioral changes 
(Walker et al., 2007). 
 
Parenting factors like cognitive stimulation or learning opportunities facilitates early 
cognitive development. Several studies examined the effect of stimulation or intervention on 
children from developing countries, including children living in poverty, which strongly 
supports the importance of early cognitive intervention for facilitating better cognitive and 
non-cognitive outcomes (Grantham-McGregor et al., 1991; Gardner et al., 2003; Eickmann et 
al., 2003; Kagitcibasi et al., 2001; Magwaza, 1991). Research revealed three aspects of 
parenting associated to young children’s cognitive and social-emotional competence: 
cognitive stimulation, caregiver sensitivity and responsiveness to the child, and caregiver 
affect (National Research Council and Institute of Medicine, 2000). Regarding maternal 
sensitivity and responsivity several researches reported that these factors are associated with 
more secure infant attachment (Posada et al., 1999; Eomlinson et al., 2005) and higher 
cognitive ability (Agarwal et al., 1992) respectively. Appropriate caregiver-child interactions 
facilitate early social-emotional development and learning materials promote age-appropriate 
language and problem-solving skills (Walker et al., 2007). Furthermore, maternal depression 
is another risk factor that causes reduced levels of cognitive function and higher levels of 
behavior problems (Patel et al., 2003). These factors discussed above are the part of maternal 
cognitive function which implies that there might be a link between factors evolved from 
maternal cognitive state and child development. Rubalcava and Teruel (2004) showed that 
maternal cognitive ability works as an important factor in progressing her children’s height, 
even after controlling for child’s age and gender, parental age, mother’s and father’s years of 
schooling and mother’s height.  
 
Iodine deficiency and iron deficiency anemia threatens the development of many 
children. Recent research highlights the evidence for other risk factors encompassing 
intrauterine growth restriction, malaria, lead exposure, HIV infection, institutionalization, and 
exposure to societal violence (Walker et al., 2011). Notably, breastfeeding and higher 

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maternal education are emerged as protective factors in new research, which attenuate 
adverse consequences of risk factors that compromise children’s development. It is worth 
mentioning that substantial improvement in development is unlikely to be made without also 
increasing early learning opportunities (Black et al., 2005), though there has been recent 
attention to the effect of nutrition on development (Victora et al., 2008). Non-US intervention 
studies showed that cognitive benefits were better in case of interventions having stimulation 
and education components compared with those involving nutrition or economic assistance 
only (Nores & Barnett, 2009). In Bangladesh, research revealed that almost 60% children are 
exposed to risk of insufficient development caused by high prevalence of LBW (22%), 
stunting (41%), and poverty (43%), and lack of early stimulation due to low parental 
knowledge (UNICEF, 2005; Hamadini et al., 2010). Most of the data from developing 
countries including Bangladesh mainly focused on cognitive and motor outcome with less 
emphasis on maternal cognitive ability. This is why, in addition to the existing information, 
we need to assess maternal cognitive ability and neurobehavioral development in order to 
prepare appropriate intervention particularly for disadvantaged children living in poverty in 
Bangladesh. 
 
It is clear from the previous studies on poor populations that disadvantaged children 
require not only good health, nutrition, and wealth but also supportive and caring 
environments at home and cognitive stimulation in order to achieve their developmental 
potential as in the case of Bangladesh. According to Lancet review, most disadvantaged 
children get the maximum benefit of intervention (Engle, 2011). Cognitive function of 
parents, especially mothers, is crucial for having the optimum outcome from intervention. 
However, little is known regarding the importance of mother’s cognitive functioning 
influencing different domains of her young children’s neurobehavioral developmental 
outcome mediated by parenting, particularly who are from disadvantageous community in 
Bangladesh, residing in poverty. We know of no other study, however, that directly 
emphasizes maternal cognitive function on different domains of development of 
disadvantaged children in Bangladesh.  
 
We, therefore, plan to examine the association of disadvantaged children’s 
neurobehavioral development i.e., communication, motor skills, problem-solving, and 
personal-social skills and mother’s cognitive function.  
 
Hypothesis: Mothers with better cognitive function will have children with better 
neurobehavioral development. 
 
Objectives: The specific objectives of the study are (a) to measure the maternal cognitive 
function, (b) to assess the neurobehavioral development of children. 
 
 
Methods 
 

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Participants 
A total of 200 mother-child dyads will participate in the study. Data will be collected by the 
researcher. Age range of children will range from 12-42 months residing in the slum area 
located in the city of Dhaka.  
Inclusion criteria  
 
 
Age: 12-42 months on enrolment 
 
 
Sex: both male and female 
 
 
Nutritional status: weight-for-age z score (WAZ)>-3SD 
 
 
Consent: written consent provided by parents 
 
Exclusion criteria 
Any child with – 
 
 
Developmental anomalies, 
 
 
Known chronic illnesses like epilepsy, tuberculosis, 
 
 
Twins and multiple births, 
 
 
Parents not consenting 
Sample Size Calculation 
Sample size is calculated assuming 5% level of significance, 80% power, an improvement of 
0.30 SD  neurocognitive developmental scores of children between high and low scorer 
mother’s group, and 15% drop outs, based on the formula below: 
 
n = 










f
sd
2
2
1
2
2
 
Where, 
n = sample size per group,  
sd=Standard deviation of population=1,  
M1-M2=Difference between the groups assumed=0.30 SD,  
=80% power and 5% significance=8 
We need to enroll 150 mother-child dyad. 
 
Measurements 
The following measurements will be applied upon all enrolled children’s mother: 
Bayley Scales of Infant and Toddler Development (BSID-III): Neurobehavioral development 
of children will be assessed on the revised version of questionnaires of BSID-III. It will be 
used to assess cognitive, language and motor development of the children. The test has been 
used in many developing countries, and has been the instrument of choice for child 
development and nutrition research at this age in other countries like Indonesia and Brazil. It 
usually takes about an hour to test the children. 
 
The Bangla Adaptation of Mini-Mental State Examination (BAMSE): The Bangla adaptation 
of Mini-Mental State Examination (BAMSE) will be used to assess the cognitive function of 
mothers. BAMSE is the Bangla adaptation of Mini-Mental State Examination (MMSE). 
MMSE (Folstein et al., 1975) is a commonly used brief global instrument that measures 
cognitive abilities having orientation to time and place, memory and attention, language 

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skills, and visuo-spatial abilities. A good association (r=0.57) was found between the MMSE 
and BAMSE instruments (Kabir & Herlitz, 2000). Test-retest reliability of BAMSE was 
satisfactory (r=0.70) and BAMSE was found to be less sensitive to age and education than the 
MMSE (Kabir & Herlitz, 2000).  
             
Anthropometry: Weights, heights, Mid-upper arm circumference (MUAC), and head 
circumference of all the study children and their mothers will be measured according to 
standard techniques (Lohman et al., 1989; WHO, 1983). Afterwards these anthropometric 
measures will be converted into height-for-age (HAZ), weight-for-height (WHZ), and 
weight-for-age (WAZ). 
 
 Socioeconomic status (SES): Information will be obtained on the families’ house-hold 
possessions, standard of housing, family structure, and parental education and occupation. 
The indices described will be calculated to measure the socioeconomic status of the family: 
1) housing, on the basis of the condition of the roof and walls of the house and presence or 
absence of electricity in the house; 2) sanitation, according to ratings of type of latrine and 
availability of water inside or outside the house; 3) assets, based on the possession of certain 
household items; and 4) crowding, composed of the number of people per room. 
 
Procedures 
Data Acquisition 
Standard data collection procedures will be followed in the study. The author of this research 
proposal will conduct a house-to-house survey in the study area. At first, the general purpose 
of the study will be briefed to the parents. After having written consent from the parents, they 
will be asked for information about their children’s development (extended ASQ), and their 
cognitive function (BAMSI). Anthropometric measures will be taken both for mothers and 
their children in order to have Body Matched Index (BMI). After administration of the all 
questionnaires, mothers will be interviewed to obtain information on socio-demographic 
characteristics. Thus data collection will be completed approximately in three months. 
 
Data Analysis 
Participants’ responses will be scored according to the scoring systems of the ASQ, BAMSE, 
and other measures. Data will then be fed to a personal computer and analyzed using the 
SPSS, version 20. Transformations will be used to normalize the variables when necessary. 
Data will be analyzed in multiple regression analysis in order to see the relationship between 
maternal cognitive ability and different domain of child development. 
 
Expected Result and Impact 
It is expected that the impact of maternal cognitive function on neurobehavioral development 
will be considerable.  
 
Although there are few national data for mother’s cognitive ability and child’s development 
in Bangladesh, but it can be said that many disadvantaged children are exposed to various 

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risks for poor development including poverty, malnutrition, poor health and un-stimulating 
home environment or lack of learning opportunities. Due to poor development, children do 
poorly in school and subsequently transfer poverty to the next generation. The second UN 
Millennium goal is to ensure that all children complete primary schooling. The result will 
help policymakers to take appropriate intervention programs to improve early child 
development, which, in turn, will achieve satisfactory educational performance. To reach the 
MDG and to stop the intergenerational transmission of poverty the findings of proposed study 
will play an important role.  
 
 
Currently, there are no accepted indicators for child development in Bangladesh. The 
expected result will help develop country’s indicators for child development. Furthermore, 
the result will provide information to help the setting programs and policies for early 
childhood development to benefit the disadvantaged children and reduce the persistent 
inequalities in child development. The proper child development will help make economical 
and social development of the country. 
 
 
 
 
Time Line 
The time plan of the study is described as under 
Works 
Year 
1 
2 
3 
Quarters Quarters 
Quarters 
1 2 3 1 2 3 1 
2 
3 
Preparatory 
works 
(Manual, 
SOP, 
questionnaire preparation) 
x  
 
 
 
 
 
 
 
Site selection 
x  
 
 
 
 
 
 
 
Training 
 
x  
 
 
 
 
 
 
Screening of 1-3.5yr old children & 
enrolment 
 
x  
 
 
 
 
 
 
Assessment  
 
x x  
 
 
 
 
 
Data entry, cleaning & preliminary analysis 
 
 
 
x  
 
 
 
 
Start writing introduction & method section 
  
 
 
 
x  
 
 
 
Synthesize results & thesis writing 
 
 
 
 
 
x  
 
 
First draft of the PhD thesis 
 
 
 
 
 
 
x 
 
 
First Seminar 
 
 
 
 
 
 
 
x 
 
Review & rewrite the thesis 
 
 
 
 
 
 
 
x 
 
Second Seminar 
 
 
 
 
 
 
 
 
x 
Submission of PhD thesis 
 
 
 
 
 
 
 
 
x 
Dissemination 
 
 
 
 
 
 
 
 
x 
 

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