Original Article

Developmental risk factors in Vietnamese preschool-age children:Cross-sectional survey

Nguyen Huu Chau Duc

Department of International Health and Medicine, Graduate School of Tokyo Medical and Dental University, Tokyo, Japan andDepartment of Pediatrics, Hue University of Medicine and Pharmacy, Vietnam

Abstract Background: Early childhood development (ECD) strongly influences children’s basic learning, school success, economicparticipation, social citizenry and health. Although some risk factors related to childhood development are documented,further exploration is necessary considering various sociodemographic, nutritional, and psychosocial factors. This studyinvestigated factors affecting ECD in Vietnamese preschoolers.Methods: We used data from the representative, cross-sectional round of the Vietnam Multiple Indicator Clusters Survey2011. Early Childhood Development Index questionnaires were administered to mothers of all children aged 36–59 monthsin the household (n = 1459). Descriptive statistics and multivariate logistic regression were used in the analysis.Results: In Vietnam, 17.2% of children did not reach their full developmental potential within the first 5 years. Children whohad been breast-fed (AOR, 2.78; 95%CI: 1.28–6.02), attended preschool (AOR, 1.75; 95%CI: 1.28–2.39), were of majorethnicity (AOR, 2.41; 95%CI: 1.55–3.74), had a mother with secondary or higher education (AOR, 1.69; 95%CI: 1.19–2.38)and had relatives who engaged with them in four or more activities that promote learning (AOR, 1.55; 95%CI: 1.13–2.14) weremore likely to have a normal developmental trajectory. Furthermore, children who experienced physical punishment andstunting were 0.69-fold (95%CI: 0.51–0.95) and 0.71-fold (95%CI: 0.51–0.98) less likely to be on track for ECD, respectively.Conclusions: The risk factors associated with delayed ECDwere low level of maternal education; family ethnicity; lack ofpreschool attendance; relatives who did not engage with them in learning; physical punishment; not being breast-fed; andstunting.

Key words early childhood development, literacy–numeracy, physical capacity, social–emotion, Vietnam.

Early childhood development (ECD) is considered to be one of themost important phases in a person’s life and a determinant ofhealth, wellbeing, learning and behavior across the life span.ECD has a strong impact on one’s basic learning, school success,economic participation, social citizenship and health later in life.As a result, healthy ECD – in physical, social–emotional, andlanguage–cognitive aspects – is fundamental not only to successand happiness during a person’s childhood, but also throughoutone’s life course.

It is estimated that >200 million children in developing coun-tries do not reach their full potential in the first 5 years. Childrenliving in these developing countries are exposed to multiple riskfactors including poverty, malnutrition, poor health, and non-stimulating home environments, which negatively affect theirphysical, social–emotional, and language–cognitive development.1

Some sociodemographic and nutritional factors related to ECDsuch as household wealth, maternal education, place of residence,gender, stunting, as well as psychosocial factors such as early child-hood education programs have been studied.2–11 Several studies

found a link between socioeconomic status and children’s cogni-tion3 and school attainment.4 A study from Madagascar showedthat preschool-age children from the wealthiest families or whosemothers had secondary education performed better across a widerange of cognitive and language tests.5 Wealth quintile was relatedto IQ at 8 years in Philippines,6 and cognitive scores at 9 years inIndonesia.7 Poverty was found to have multiple adverse effectson children. It is associated with poormaternal education, increasedmaternal stress and depression8–10 and inadequate stimulation athome.11 All these factors are detrimental to child development. Pre-vious studies have also shown that children living in conditions ofpoverty suffer from delayed growth and increased risk of growthfaltering.12,13 Other factors, however, such as ethnicity and physi-cal punishment also need to be studied.

Moreover, despite the compelling evidence for poor child de-velopment in low- and middle-income countries, there is a paucityof research on this topic in Vietnam. Furthermore, the existing stud-ies are hindered by some methodological limitations. For example,a cross-sectional study from Vietnam found associations betweenchronic malnutrition, as evidenced by stunting, and poor cognitivefunction among 3055 children aged 9years,14 but that study samplewas limited to three districts of northern Vietnam. Another studycovered only one district of northern Vietnam.15

Based on these considerations and using nationally representa-tive population-based data from Vietnam, we therefore examined

Correspondence: Nguyen Huu Chau Duc, MD, Department of Interna-tional Health and Medicine, Graduate School of Tokyo Medical andDental University, Tokyo, Japan. Email: nguyenhuuchauduc@gmail.comReceived 24 September 2014; revised 9 January 2015; accepted 15

June 2015.

© 2015 Japan Pediatric Society

Pediatrics International (2016) 58, 14–21 doi: 10.1111/ped.12748

whether, in addition to known risk factors, other unknown riskfactors such as ethnicity and physical punishment are associatedwith ECD (literacy–numeracy, physical capacity, social–emotion,and learning) among children aged 36–59months. The presentfindings may help to fine-tune suitable national strategies, ensuringcontinued improvement in child development programming inVietnam, and in South-east Asia in general.

Methods

Data sources and sampling

We used data from the representative, cross-sectional round of theVietnam Multiple Cluster Survey (MICS 2011) conducted during2010–2011. MICS 2011 was conducted by the General StatisticsOffice in Vietnam and used a method designed by the UnitedNations Children’s Fund (UNICEF).The surveys included threesets of questionnaires: a household questionnaire; a questionnaireadministered only to women of reproductive age (15–49 years)living in the household; and a questionnaire regarding childrenunder 5 years living in the household, administered to the womenor caregivers. The questionnaires were drafted in English and thentranslated into Vietnamese, the national language of Vietnam. Thetranslations were reviewed by experts and volunteers, and a pilotstudy was conducted as a validation exercise.

Among the women aged 15–49years whowere deemed eligibleto complete the women’s questionnaires on maternal and childhealth behaviors and outcomes, 11663 of 12115 completed thequestionnaire, yielding a response rate of 96.3%.

The questionnaire for children was administered to all mothersor caregivers who cared for a child under 5 years living with them.Only information on children aged 36–59 months was used for theanalysis, with a final sample size of 1459. Detailed descriptions ofthe study design and the methods used for data collection are acces-sible online in household survey reports.16

Measurement

The 2011 MICS used a 10-item module to measure Early Child-hood Development Index (ECDI). A validation study of the recom-mended items was conducted in order to ensure reliability andfeasibility of the scale. Moreover, the reliability of those items(both test–retest and inter-rater reliability) was also checked beforeimplementation of the module.17 Each of the 10 items was used todetermine whether children were developmentally on track in oneof the four domains: literacy–numeracy, physical capacity,social–emotion, and learning. To measure literacy–numeracy, thesurvey asked whether the child could achieve at least two of thesetasks: name at least 10 letters of the alphabet; read at least foursimple, common words; know the name and recognize the symbolsof all numbers from 1 to 10. To measure physical capacity, thecaregivers were asked whether the child was able to pick up a smallobject such as a stick or a rock from the ground with two fingers;and whether the caregivers did not indicate that the child was some-times too sick to play. Social–emotion was measured according towhether at least two positive responses to the following questionswere recorded: if the child gets along well with other children; ifthe child does not kick, bite, or hit other children; or if the child

does not get distracted easily. In addition, learning domain wasmeasured according to whether the child could follow simple direc-tions on how to do something correctly; or, when given somethingto do, was able to do it independently. The ECDI is calculated asthe percentage of children who are developmentally on track in atleast three of these four domains. Detailed descriptions of themethods are accessible online in household survey reports.16

We included several theoretically pertinent sociodemographicfactors as independent variables. Household wealth status wasdetermined based on a wealth score calculated by principal compo-nent analysis of an asset and household wealth index. Each house-hold was then weighted by the number of household members, andthe household population was divided into five groups of equalsize, from the poorest quintile to the richest quintile, based on thewealth scores of the households in which the household memberswere living. In the present study, we considered two groups ofwealth status: poorest (first quintile) versus second–fifth quintile.There are two reasons for this grouping: (i) the first quintile(poorest) identifies households that both have the lowest absolutelevel of wealth and, by virtue of their location in the ranking ofhouseholds on wealth, are also relatively the poorest (comparingthe first quintile [poorest] to other quintiles allows us to clearlysee the effect of both poverty and ECD); and (ii) the poorest hasvery limited income, especially in rural Vietnam: 20% of house-holds belonging to the first quintile possess only 5.7% of totalincome compared with the other quintiles.18

Maternal education was defined in terms of the formal educationsystem of Vietnam: no education (0years), primary (1–5 years),secondary (6–9 years), and higher (≥10years). Vietnam is an ethni-cally diverse country, with 54 different ethnic groups. People whobelong to an ethnic minority tend to be marginalized and discrimi-nated against. This background affects their social status prospectsand opportunities and is often associated with poor mental and phys-ical health.19 Therefore, a distinction was made between womenaccording to ethnicity: belonging to the majority (Kinh group), orto a minority (non-Kinh group). Place of residence was categorizedas rural or urban. Parity was categorized as one, two, three, or more.

Psychosocial factors including early learning, support forlearning, and exposure to violence were used. Data on disciplinarypractices were collected in MICS using a modified version of theshort form of the Parent to Child Conflict Tactics Scale orCTSPC.20 The questionnaire was addressed to the mother of onerandomly selected child 36–59 months of age in each household.The physical or corporal punishment practices covered in the ques-tionnaire included shaking, slapping or hitting the child on variousbody parts (with or without an implement). A binary variable wascreated to assess attitudes towards physical punishment based onwhether the mothers responded to the necessity of using physicalpunishment to raise the child with yes versus no. Information ona number of activities that support early learning included theinvolvement of the child’s relatives in the following activities:reading books or looking at picture books, telling stories, singingsongs, taking the child outside the home, playing with the childand spending time with the child to help naming, counting, or draw-ing things. Preschool attendance in an organized learning or childeducation program was created as a binary variable (yes vs no).

Developmental risk factors in ECD 15

© 2015 Japan Pediatric Society

We also included the child malnutrition variables of stuntingand wasting in the analysis. Stunting is defined using height forage, while wasting is determined using weight for height. Childrenwhose height for age or weight for height are >2SD below themedian of the reference population are classified as moderately orseverely stunted or wasted.16

Statistical analysis

Descriptive statistics were used to identify socioeconomic anddemographic factors in ECD. Fully adjusted models were createdto analyze ECDI as well as its domain. All covariates were enteredsimultaneously in multiple regression models. Multicolinearity inthe logistic regression analysis was investigated in this study byexamining the variance of inflation factors, which was <2.0.Adjusted OR (AOR) was estimated to assess the strength of theassociations, and 95%CI was used for significance testing. StataMP version 11 (Stata, College Station, TX, USA) was used forall analyses.

Ethics

The present study was based on secondary data analysis of existing,publicly available survey data from which all personally identifi-able information had been removed. Before participating in thesurvey, all the participants were asked to provide informed consentafter being read a document emphasizing the voluntary nature ofthis project, outlining the potential risks, and explaining that theinformation gathered would be used to assess health-care needsand to plan health services. Each participant was allowed towithdraw from the study at any time. The confidentiality of theentire data set was maintained at all stages of data collection.

Results

Descriptive statistics

Table 1 shows that most of children aged 36–59 months wereliving in rural areas (73.5%) and belonged to the major ethnicity(87.4%). Seventy seven percent of children were living in2nd–5th quintile households and 73.3% of children had a mother withsecondary or higher education. The female :male ratio was 1:1.01.

Table 2 shows that 71.9% of children aged 36–59 months wereattending early childhood education programs inVietnam. Approx-imately three-fourths (76.8%) of children had adults (relatives) whoengaged with them in more than four activities that promote learn-ing and school readiness during the 3days preceding the survey.

Only 16.3%ofmothers believed that it was necessary to use phys-ical punishment to raise/educate children, but 61.7% of children ex-perienced at least one physical punishment. Spanking with barehand (52.1%) was the most common punishment used by mothers.Approximately 19.1% of mothers reported that they had hit theirchildren with a hard object at least once on the bottom or elsewhere;and 17.4% reported hitting them on the hand, arm or leg. Childrenalso experienced severe discipline such as hitting on face, head orears (2.8%), and beating up with an implement (0.3%; Table 2).

Table 3 lists ECDI for children aged 36–59 months in Vietnam.The percentage of children who were developmentally on trackwas 82.8%. Of note, 97.7% of children were on track in the

physical domain while only 24.1% of children were on track in theliteracy–numeracy domain. The percentage of children who weredevelopmentally on track for the learning and social–emotional do-mains were 91.3% and 88.6%, respectively. Regarding the ECDIsubscales, the highest percentage of children (36.8%) knew thenames and recognized the symbols of all numbers from 1 to 10 inthe literacy–numeracy domain. In the physical and social–emotional domains, the highest percentage was observed for thecomponents picking up a small object with two fingers (91.6%)and getting along well with other children (97%). Learning domainwas measured according to whether the child could follow simpledirections on how to do something correctly (88.4%), or, whengiven something to do, was able to do it independently (77.2%).Given that some children had a positive response in two compo-nents, one component, or none in this domain, when positive re-sponse in at least one component was used, 91.3% of childrenwere developmentally on track in the learning domain.

Multivariate analysis

Table 4 lists the association of ECDwith sociodemographic and psy-chosocial factors. Children whose mothers had secondary or highereducation (high education) were 1.69-fold (95%CI: 1.19–2.38) morelikely to achieve their full potential compared with the children of

Table 1 Characteristics of children aged 36–59 months, Vietnam,2011 (n = 1459)

Characteristic n %

Economic statusPoorest 336 23.0Poorer 272 18.6Middle 274 18.7Richer 315 21.6Richest 263 18.0First quintile 336 23.02nd–5th quintiles 1123 77.0Maternal educationNo schooling 97 6.7Primary 292 20.0Secondary 606 41.5Higher 464 31.8Under secondary (low education) 389 26.7Secondary or higher (high education) 1070 73.3Place of residenceUrban 387 26.5Rural 1072 73.5EthnicityMinority (Non-Kinh) 184 12.6Majority (Kinh) 1275 87.4Age36-47 months 764 52.448-59 months 695 47.6GenderFemale 733 50.3Male 726 49.7Breast-feeding statusNever 35 2.4Formerly breast-fed 1424 97.6Nutritional statusStunting 317 21.8Wasting 54 3.7

16 NHC Duc

© 2015 Japan Pediatric Society

mothers with below secondary education. Children with high educa-tion mothers were also 1.83-fold (95%CI: 1.15–2.91) and 2.9-fold(95%CI: 1.28–6.58) more likely to be developmentally on track inthe learning and physical domains, respectively.

Children residing in urban areas were 1.6-fold (95%CI:1.21–2.12) and 2.06-fold (95%CI: 1.12–3.76) more likely tobe in the normal range in literacy–numeracy and learning,respectively, compared with rural children. Children in themajor ethnic group (Kinh) were 2.41-fold (95%CI: 1.55–3.74)more likely to be on track according to ECDI. Kinh childrenwere 2.45-fold (95%CI: 1.42–4.25) and 2.66-fold (95%CI:1.57–4.52) more likely to have better outcomes in the social–

emotion and learning domains, respectively. Furthermore, girlswere 0.42-fold (95%CI: 0.20–0.86) less likely to be develop-mentally on track in the physical domain compared with boys.

With regard to psychosocial factors, children attending in anearly childhood education program were 1.75-fold (95%CI:1.28–2.39), 2.89-fold (95%CI: 2.02–4.15), and 2.39–fold(95%CI: 1.58-3.62) more likely to reach their potential in over-all development, as well as in the literacy–numeracy, and learn-ing domains, respectively. Furthermore, children who hadrelatives who engaged with them in more than four activitiesthat promote learning and school readiness were 1.55-fold(95%CI: 1.13–2.14), 1.89-fold (95%CI: 1.31–2.75), and 2.01-fold

Table 3 ECDI for children aged 36–59 months in Vietnam, 2011 (n = 1459)

Early childhood development index (ECDI) n %

On track† 1208 82.8Off track 250 17.2

Developmentally on track in ECDI domainsLiteracy–numeracy‡ 351 24.1Physical§ 1426 97.7Social–emotional¶ 1292 88.6Learning†† 1331 91.3

ECDI domain componentsLiteracy–numeracy domainName at least 10 letters of the alphabet 350 24.0Read at least four simple, common words 310 21.2Know the name and recognize the symbols of all numbers from 1 to 10 537 36.8

Physical domainPick up a small object with two fingers 1336 91.6Did not indicate that the child was sometimes too sick to play 1123 77.0

Social–emotional domainGet along well with other children 1415 97.0Not kick, bite, or hit other children 1148 78.7Not get distracted easily 978 67.0

Learning domainFollow simple directions on how to do something correctly 1290 88.4Able to do something independently 1126 77.2

†At least three ECDI domains fulfilled; ‡at least two literacy–numeracy components achieved; §both of two physical components achieved;¶at least two social–emotion components achieved; ††at least one learning component achieved. ECDI, early childhood development index.

Table 2 Psychosocial factors for children aged 36–59 months in Vietnam, 2011 (n = 1459)

Indicators n %

Attendance at an early childhood education program 1049 71.9Adult engaged with them in stimulating activities in the past 3 daysRead books to or looked at picture books with the child 670 46.0Told stories to the child 979 67.1Sang songs to the child or with the child, including lullabies 1202 82.4Took the child outside the home, compound, yard or enclosure 1253 85.9Played with the child 1318 90.3Named, counted, or drew things to or with the child 1168 80.1Engaged in four or more activities with the child 1120 76.8Physical punishmentShaking 110 7.6Hitting on the bottom with bare hand 760 52.1Hitting child on the bottom or elsewhere on the body with hard object 278 19.1Hitting on the hand, arm, or leg 254 17.4Hitting on the face, head or ears 41 2.8Beating up with an implement (repeated hitting with maximum force) 3 0.3Experienced at least 1 physical punishment 900 61.7Believe physical punishment is necessary to raise/educate a child 238 16.3

Developmental risk factors in ECD 17

© 2015 Japan Pediatric Society

Tab

le4

Factorsassociated

with

ECDIam

ongchild

renaged

36–59monthsin

Vietnam

,2011(n

=1459)

Independent

variables

Early

child

developm

entindex

Social–emotionald

omain

Literacy–num

eracydomain

Learningdomain

Physicaldomain

AOR(95%

CI)

AOR(95%

CI)

AOR(95%

CI)

AOR(95%

CI)

AOR(95%

CI)

Sociodem

ographicfactors

Household

wealth

Poorestq

uintile

——

——

—2nd–5thquintiles

0.69

(0.46–1.04)

0.49*(0.29–0.85)

0.95

(0.63–1.42)

1.20

(0.72–2.01)

0.66

(0.25–1.74)

Maternaleducatio

nLow

education

——

——

—Higheducation

1.69**

(1.19–2.38)

1.15

(0.76–1.75)

1.37

(0.95–1.98)

1.83*(1.15–2.91)

2.90*(1.28–6.58)

Placeof

residence

Rural

——

——

—Urban

1.39

(0.96–2.02)

0.76

(0.52–1.12)

1.60**

(1.21–2.12)

2.06*(1.12–3.76)

0.85

(0.35–2.07)

Ethnicity

Minority

——

——

—Majority

2.41***(1.55–3.74)

2.45**

(1.42–4.25)

1.05

(0.63–1.75)

2.66***(1.57–4.52)

1.59

(0.59–4.27)

Gender

Male

——

——

—Female

0.82

(0.61–1.09)

1.31

(0.94–1.83)

1.03

(0.80–1.33)

0.69

(0.47–1.03)

0.42*(0.20–0.86)

Parity

1or

2child

ren

——

——

—3or

more

0.85

(0.62–1.16)

0.81

(0.57–1.17)

0.96

(0.72–1.28)

0.95

(0.62–1.46)

0.93

(0.44–1.97)

Nutritio

nalstatus

Breast-feeding

Never

——

——

—Fo

rmerly

2.78**

(1.28–6.02)

2.22

(0.97–5.08)

1.95

(0.77–4.93)

7.66***(3.23–18.17)

4.34*(1.04–18.14)

Wastin

gNo

——

——

—Yes

0.89

(0.43–1.81)

0.73

(0.33–1.62)

0.83

(0.40–1.69)

1.09

(0.39–2.99)

1.32

(0.21–8.38)

Stuntin

gNo

——

——

—Yes

0.71*(0.51–0.98)

1.00

(0.66–1.52)

0.49***(0.34–0.72)

0.54**

(0.36–0.82)

0.27***(0.13–0.55)

Psychosocialfactors

Early

child

hood

educationprogram

Non-attendance

——

——

—Attendance

1.75***(1.28–2.39)

1.35

(0.93–1.96)

2.89***(2.02–4.15)

2.39***(1.58–3.62)

1.39

(0.67–2.89)

Adultengagedwith

them

inlearning

No

——

——

—≥4

activ

ities

1.55**

(1.13–2.14)

1.89**

(1.31–2.75)

2.01***(1.39–2.91)

0.92

(0.59–1.44)

0.98

(0.45–2.13)

Motherbelievesin

physicalpunishment

No

——

——

—Yes

1.11

(0.76–1.63)

0.75

(0.49–1.14)

0.48**

(0.32–0.73)

2.06*(1.13–3.76)

1.02

(0.41–2.49)

Physicalpunishment

No

——

——

—Yes

0.69*(0.51–0.95)

0.62**

(0.43–0.88)

1.01

(0.75–1.36)

0.77

(0.51–1.19)

0.91

(0.43–1.96)

*P<

0.05,**P

<0.01,*

**P<

0.001,

Allcovariates

adjusted

inthemodel.E

CDI,earlychild

hood

developm

entindex.

18 NHC Duc

© 2015 Japan Pediatric Society

(95%CI: 1.39–-2.91) more likely to have better development interms of ECDI, social–emotional, and literacy–numeracy, respec-tively. In contrast, children who experienced physical punishmentwere 0.69-fold (95%CI: 0.51–0.95) and 0.62-fold (95%CI:0.43–0.88) less likely to be developmentally on track in ECDIand social–emotional aspects.

Regarding nutritional status, children who had been breast-fedwere 2.78-fold (95%CI: 1.28–6.02) more likely to have ECDI inthe normal range. Breast-feeding was also associated with 7.66-fold(95%CI: 3.23–18.17) and 4.34-fold (95%CI: 1.04–18.14) improve-ment in learning and physical development, respectively. Childrenwith stunting were 0.71-fold (95%CI: 0.51–0.98) less likely tohave ECDI in the normal range. Stunted children also were 0.49-fold (95%CI: 0.34–0.72), 0.54-fold (95%CI: 0.36–0.82), and0.27-fold (95%CI: 0.13–0.55) less likely to be developmentallyon track in the literacy–numeracy, learning, and physical domains.

Discussion

This is the first study to examine the factors associated with ECD inVietnam using a large, nationally representative survey. Given thelarge nationally representative survey and adequate sample size,this paper provides an unbiased analysis, and has uncovered twomajor findings. First, 17.2% of Vietnamese children did not reachtheir full developmental potential within the first 5 years. Second,having a well-educated mother, having been breast-fed, attendingan early childhood education program or having relativesengaged in their learning are positive factors associated with gooddevelopmental progress in children aged 36–59 months. In con-trast, stunting was found to be a negative factor for child develop-ment. These factors were similar to those reported in otherregions.14,21–39 In addition, the present study identified that ethnic-ity and physical punishment play a role in child development.

Despite assistance from the government of Vietnam, the minor-ity ethnic groups (non-Kinh) still lag behind in terms of living stan-dards. Households of these groups in Vietnam are not only poorerbut also more vulnerable to various shocks than those in the majorethnic group. Children of ethnic minorities have less access toeducation, higher dropout rates, and higher rates ofstunting,19,40 which may partly explain the lower prevalenceof on-track development. We also found that children belong-ing to the minority ethnic groups had mothers with lowereducation and had higher rates of stunting. Although somesmall-scale studies were conducted in Vietnam to identify therisk factors of childhood development, they ignored ethnicity.In future studies, ethnicity should be included as an importantrisk factor of child development in Vietnam.

The underpinning association between childhood exposure tophysical punishment and increased risk of social–emotional andECDI problems may be explained by the fact that physical punish-ment is associated with a range of mental health problems inchildren. These problems are: depression, unhappiness, anxiety,feelings of hopelessness because of increasing cortisol or of thechemical disruption of the brain’s mechanism for regulatingstress.41–46 Therefore, they may experience maladaptive wear andtear on their physiological response systems, which are then

activated in response to mental health problems. As a result, childrenare less capable of habituating to new events, or regulating their ownemotional reactions in adaptive ways. In addition, physical punish-ment during childhood may reflect customs and habits that give pri-ority to parental rights in Vietnamese culture. It is normally acceptedthat parents and other members of the family should discipline theirchildren if they make mistakes or refuse adults’ orders.47 Further-more, provision against violence and abuse in the Law on theProtection, Care and Education of Children 1991 (amended 2004),the Law on Marriage and Family (art.26) and the Law on DomesticViolence Prevention and Control 2007 were not interpreted asprohibiting all physical punishment in childrearing.48–50 Thesefactors might explain the widely accepted practice of physicalpunishment in child rearing. This evidence indicates that physicalpunishment is an important factor for clinicians as well as policymakers, in that it has a negative impact on early child developmentin Vietnam, and requires effective strategy implementation to pre-vent and eliminate domestic violence and abuse.

Early learning facilitating cognitive development includes pre-school education attendance and adult engagement in stimulatingactivities that promote early learning and school readiness. Lackof early learning opportunities and appropriate caregiver–childinteractions decreased the developmental potential of children.Early learning had a beneficial effect of cognitive stimulation inchild task orientation, social behaviors, self-confidence…21–24

Also, children who attended an early childhood education programand who had adult household members who engaged with them inmore than four activities that promote learning and school readi-ness were more likely to reach their potential in overall develop-ment, as well as in the social–emotional, literacy–numeracy, andlearning domains. This strongly supports the importance of earlycognitive stimulation during ECD.

The present study also found that although 82.8% of childrenreached their full developmental potential, the rate of childrenwho were in the normal range for literacy–numeracy was low(24.1%). Literacy and numeracy are core life skills and the acquisi-tion of these abilities has a profound impact on individuals, fami-lies, communities and the nation.51 Strong evidence indicates thatearly learning stimulation from the family such as book readingor story telling, has a significant positive impact on child education,especially literacy and numeracy.25,26 Although home-based edu-cation plays the most important role in supporting the holistic de-velopment of children in the early years, the knowledge and skillsof parents and caregivers of early childhood care and educationare very limited.52Additionally, learning material for children athome also remains limited: only 19.6% of children aged <5yearslived in households where at least three children’s books werepresent, and 49.3% had two or more toys to play with.16 We alsofound that stimulating activities such as book reading or storytelling were limited at the household level. Furthermore, onmultivariate analysis, children who attended an early childhood ed-ucation program and had an adult household member who engagedwith them in more than four activities that promote learning andschool readiness were twofold more likely to achieve the coreeducational skills compared with their counterparts. These findingsfrom a national representative sample are in line with previous

Developmental risk factors in ECD 19

© 2015 Japan Pediatric Society

studies,27,28 and indicate that early learning-stimulating activitiesare important in ECD assessment. This also confirms that develop-ment of good literacy and numeracy skills during the early years iscritical to ECD, and essential in Vietnamese society.

Regarding nutritional status, previous studies showed that mal-nutrition, especially stunting, had a negative influence on cognitivedevelopment,29–33 and that breast-feeding was associated withimproved developmental outcomes.34–37 We found that stuntedchildren not only experience more difficulty in reaching full phys-ical development but also have less chances to reach full potentialin overall development, in literacy–numeracy and in learning.Formerly breast-fed children were more likely to be on track inoverall development, learning and physical domains comparedwith non-breast-fed children. These findings again underline theimportance of nutrition in cognitive development.

As expected, children with educated mothers had better scoresin overall development, learning and physical domains. Thesefindings are in line with previous studies and indicate that maternaleducation background affects child cognitive development bymeans of environmental organization, parental expectations andpractices, provision of materials for cognitive stimulation, andvariety in daily stimulation for the child.5,38,39

Strengths and limitations

The main strength of the present study is that the data came fromthe large and nationally representative survey performed in 2011. Arelevant subset was extracted consisting of women aged 15–49 yearswho had a live birth in the 2years preceding the survey, providing alarge sample size. The survey interviewers were trained to respondto questions about the selected topics, and the fieldwork wasmonitored through visits by representatives from the Ministry ofHealth and UNICEF.

Some limitations should be considered when interpreting thepresent findings. First, the current analysis was cross-sectional innature and involved the reporting of past behaviors; therefore, apossible recall bias existed. The recall period, however, was limitedto 2years to minimize recall bias. Second, the study was based onself-reported outcome, which might have resulted in a responsebias. MICS, however, stated that the respondents were informedof the importance of providing accurate responses and were alsoassured of the confidentiality of their responses. Third, the presentstudy can be criticized for the use of an indirect measure of house-hold wealth, but, given that reliable income and expenditure dataare difficult to obtain in developing countries, such as Vietnam,an asset-based index is generally considered a good proxy forhousehold wealth status. Finally, because the selection of variableswas constrained by the pre-existing MICS data, we were unable toinclude additional, potentially important variables. Althoughlimitations in the available data can be identified, we believe thatthe present study provides important information on areas whereinvestment and intervention are needed, to enable the children ofVietnam to achieve their full developmental potential.

Conclusions

Developmental risk factors that affect Vietnamese preschool-agedchildren were low maternal education level; lack of attendance at

an early childhood education program; not being breast-fed;relatives who did not engage with them in learning; and stunting.Ethnicity and physical punishment should also be included ascontributing factors in childhood development in the context ofVietnam. The present findings may be relevant to other settingsand also of interest to clinicians when assessing children withdifferent problems related to full developmental potential.

Acknowledgments

The author would like to thank all the teams that conducted theVietnam Multiple Indicator Cluster Survey. The author extendshis deep appreciation to his direct supervisor, Professor KeikoNakamura, Head, Department of International Health and Medi-cine, Division of Public Health, Graduate School of TokyoMedicaland Dental University, Tokyo, Japan, for her guidance andthoughtful insights. The author is also indebted to Dr MasashiKizuki, Dr Kaoruko Seino, Dr Pham Nguyen Quy, Mr HoangHuy Dung and Ms Tran Ngoc The Tu for their advice and support.The author declares no conflicts of interest.

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