social gradients in child health: why do they occur and what can paediatricians do about them?

© 2000 Blackwell Science Ltd

RESEARCH REVIEW Ambulatory Child Health (2000) 6: 191–202

Social gradients in child health: why do they occurand what can paediatricians do about them?

Nick SpencerSchool of Postgraduate Medical Education and Department of Social Policy and Social Work, University ofWarwick, Coventry, UK

ABSTRACT

Objective To consider the impact of gradients in social risk factors on birthweight, child mental health and behavioural problems within a framework to guide paediatricians contributions to the prevention of adverse outcomes.

Methods Review of fifty studies on the impact of varying levels of social risk. Results Many adverse child health outcomes show a finely graded pattern of

risk from the least to the most disadvantaged children. Reduced meanbirthweight and impaired child mental health are two important exampleswith implications for the life course. The cumulative and additive effects of risk and protective factors are the most likely explanation for socialgradients.

Conclusions/ Interventions aimed at modifying single risk factors are likely to have implications for limited influence on social gradients. Health and social policies addressing practice underlying material and social inequalities are likely to have the greatest

potential for modifying risk. Paediatricians have a role in advocacy and inensuring equality of access to their services.

Keywords advocacy, birthweight, child health, child mental health, social grandours

IntroductionSocial factors have a profound impact on child health.1

An intriguing feature of many child health outcomes isthe fine-grading of risk across social groups. Whilstthere has been attention to the highest risk groupswith many interventions directed at them, little con-sideration has been given to the implications of thesocial gradients in child health for research and inter-vention. This paper briefly reviews the evidence forfinely graded risk in child health with particular focuson birthweight and child mental health and behav-ioural problems, before discussing the possible expla-nations for these social gradients and the implicationsfor research and interventions to prevent adverse out-

comes and reduce child health inequalities. The con-cluding section proposes a framework which paedia-tricians might use to guide their contribution to theprevention of outcomes in which social risk plays asignificant part.

Social gradients in child healthPoor children are at increased risk of mortality andmorbidity in developed and developing countries.1 Therelationship applies to both the ‘new’ mortality andmorbidity (for example, sudden infant death, acci-

192 N Spencer RESEARCH REVIEW

dents and behavioural problems) as well as for the‘old’ causes of death and ill health (for example, infec-tion and malnutrition). There are very few examplesof adverse health problems for which rich children are at greater risk than poor children. Before the polio vaccine was available, polio appeared to have a reverse social gradient. This was related to earlierexposure to the natural virus among poorer childrenat a time when they were protected by maternal antibodies.2 The gradient reversed with the advent of mass polio vaccination. Eczema has also beenreported to have a reverse social gradient.3

Mortality

Perinatal mortality, neonatalmortality and postneonatalmortality are all finely gradedby social group.4 Specificcauses of perinatal mortalityshow a social gradient.5

Deaths in the perinatalperiod5 and in infancy4 dueto congenital anomalies are graded by social group.Sudden unexpected death in infancy (SUDI) hasbecome increasingly associated with extreme material deprivation;67 however, 28 out of 29 studies,undertaken over the last 40 years, in which gradedmeasures of socio-economic status (SES) wereincluded, have shown a ‘dose–response’ relationshipwith SES.8 Table 1 shows the gradient for SUDI byincome level reported in the UK study, the Confiden-tial Enquiry into Stillbirths and Deaths in Infancy.9 Thesocial gradient in mortality was thought to be lesssteep in later childhood in the UK;10 however, thisproved to be an artifact of the Registrar General’ssocial class grading, which excluded children in lone

mother households from the analysis.11 Judge andBenzeval11 demonstrate a steep gradient in all causesof mortality among children 10–14 years, with thesharpest gradients in traumatic deaths.

Morbidity

Many causes of acute and chronic morbidity in child-hood demonstrate the same gradient: pneumonia andchest infection;12 acute infections;13 bronchiolitis;14

cerebral palsy;15,16 life-limiting long standing illness.4

Birthweight and child mentalhealth are among the mostimportant child public healthissues in developed coun-tries, with major effectsacross the whole life-course. Both show strikingsocial gradients. Table 2shows data from two UKstudies of mean birth-weight against an ecologicalmeasure of material depri-

vation.17,18 The study of 210 000 births in the WestMidlands region17 between 1991 and 1993 demon-strated a 220-gm difference in mean birthweightbetween the least and most disadvantaged areas, andthe Sheffield study of more than 50 000 births over 10 years showed a similar but less steep gradient of170 gm.18 Others have demonstrated similar gradi-ents,19,20 although mean birthweights across all socialgroups in the Swedish study20 were approximately200 gm higher than those in the UK West Midlandsstudy.17

In contrast to birthweight, child mental health prob-lems are difficult to measure, with presentations

© 2000 Blackwell Science Ltd, Ambulatory Child Health 6(3), 191–202

Paediatricians have a role in advocacyand in ensuring equality of access totheir services.

Table 1: Sudden unexpected death in infancy by family income per week

Income SUDI (n = 195) Controls (n = 780) Odds ratio 95% Confidence intervals

£0–59 24 21 5.07 2.65, 9.72£60–99 58 138 1.97 1.36, 2.86£100–199 62 214 1.23 0.86, 1.76£200–299 28 167 0.45 0.28, 0.70£300–499 13 133 0.35 0.18, 0.65£500 + 5 51 0.38 0.12, 0.96c2 for linear trend 54.55 P<0.0001

RESEARCH REVIEW Social gradients in child health 193

ranging from suicide and severe depression, throughinternalizing behaviours and withdrawal to ‘acting out’and conduct disorders. Behavioural problems are themost common mental health problems presenting inchildhood. The social gradient among UK childrenmeasured by social class (Figure 1)12 and by incomelevel (Figure 2)21 is similar to that for Canadian children by income level (Figure 3).22 Suicide ratesamong adolescent boys in the UK are finely gradedby social group, with a clear trend over the last20 years toward an increasing social gradient.23 Workfrom the USA24 confirms the importance of lookingbeyond the simple contrast of poor and nonpoor; 4-year-old children who have experienced permanentand severe poverty have a higher risk of behaviouralproblems and intellectual impairment than thoseexperiencing transient, less severe poverty who, inturn, have a higher risk than nonpoor children.

Social gradients in childhood mortality and morbidityconstitute a major public health challenge. We esti-mated that 30% of the births less than 2.5 kg in the

West Midlands17 and 10% of births less than theoptimum birth weight of 3.5 kg in Sheffield18 were sta-tistically attributable to social inequality. Based on theCanadian figures, children in the lowest income fam-ilies have twice the risk of engaging in delinquentbehaviours as those in middle income families, andthree times the risk of those in the highest incomefamilies. In other words, a high proportion of childrenwould not suffer the short- and long-term conse-quences of lower than optimum birthweight andbehavioural problems if the risk for all social groupswas equivalent to that for the most privileged.

Why do social gradients inchild health occur?There has been a shift in focus of research intosocioeconomic differentials in health from a focus onpoverty and health toward ‘the continuous gradient of


Table 2: Mean birthweight by enumeration district deciles ranked by Townsend Deprivation Index – West Midlands Health Region1991–1993 and Sheffield 1991–1993

Enumeration district decile ranked by Mean birthweight – all live births (95% CIs) Mean birthweight – singletons onlyTownsend Deprivation Index West Midlands 1991–1993 (95% CIs) Sheffield 1991–1993

(n = number of births) (n = number of births)

1 (least deprived) 3410 (3402, 3419) 3397 (3352,3442)(n = 17510) (n = 1736)

2 3375 (3366,3384) 3420 (3374,3466)(n = 16003) (n = 1730)

3 3386 (3376,3395) 3372 (3324, 3466)(n = 14687) (n = 1730)

4 3375 (3366,3384) 3376 (3329, 3423)(n = 16459) (n = 1700)

5 3348 (3339,3357) 3310 (3260,3360)(n = 17454) (n =1625)

6 3341 (3333,3349) 3328 (3279,3375)(n = 19088) (n = 1747)

7 3310 (3302,3318) 3279 (3231, 3327)(n = 21580) (n = 1783)

8 3275 (3267,3282) 3236 (3189,3283)(n = 23177) (n = 1938)

9 3251 (3244,3258) 3226 (3180, 3272)(n = 27197) (n = 1911)

10 (most deprived) 3187 (3180,3193) 3224 (3178, 3272)(n = 36876) (n = 1822)



PoorestUp to £6500

Males

Females

Income groups

RichestOver £24,381

20

15

10

5

0

gPercentage of children aged 4–15 with emotional/behavioural difficulties

Perc

enta

ge o

f chi

ldre

n ag

ed 4

–15

with

emot

iona

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avio

ural

diff

icul

ties

Perc

enta

ge o

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ldre

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ed 4

–15

with

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iona

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Figure 1: Behavioural problems at age 10 years by social class, Great Britain 198012.

Figure 2: Children with emotional/behavioural difficulties by income group.21

0

5

10

15

20

VIVIIIMIIINIII

Hyperactivity

Social class

0

5

10

15

20

VIVIIIMIIINIII

Conduct disorder

Social class

0

5

10

15

20

VIVIIIMIIINIII

Social class

Anxiety

improving health from the bottom to the top of thesocioeconomic hierarchy’.25 Gradients in adult healthhave been extensively studied;26,27 however, theexplanations for gradients in child health havereceived less attention except in so far as they predictadult health outcomes.28 Explanations for the gradientin birth weight and behavioural problems are exploredin detail here. The same principles applied to the evi-dence related to birth weight and behavioural prob-lems can be applied to understanding the gradient inother child health outcomes.

Birth weight

The birth weight of an infant reflects quality of the foetalenvironment and the length of gestation, which areinfluenced by intergenerational, genetic, constitutional,dietary and lifestyle factors. It is a pivotal point in thelife-course continuum reflecting maternal health andpredicting future health in childhood and adulthood.

Table 3, adapted from a systematic review of thedeterminants of low birth weight,29 illustrates the indi-



0<$20,000

$20,000–$29,999$30,000–$39,999 $50,000–$59,999

$60,000–$69,999$80,000+

$40,000–$49,999

2

4

6

8

10

12

14

16

18

Average household income

Note: Two-parent families with children aged 4 to 11 years.

Source: Prepared by the Canadian Council on Social Development using Statistics Canada's National Longitudinal Survey of Children and Youth, 1994–95 microdata.

ercent

Per c

ent

Figure 3: Children engaging in frequent delinquent behaviours compared with average household income.22

Table 3: Risk factors for preterm and IUGR in developed countries (modified from Kramer29 pp. 719 & 722)

Preterm IUGR

Associated factor

Well established: Previous preterm birth Infant genderPrevious spontaneous abortion EthnicitySocioeconomic conditions Maternal birth weightPre-pregnancy weight ParityPrevious LBW history Maternal heightVery young maternal age Socioeconomic conditionsMaternal education Episodic illnessCigarette smoking Cigarette smokingMaternal educationGestational weight gainCaloric intake

Uncertain: Stress and anxiety Maternal haemodynamicsMaternal work Narcotic addictionEpisodic illness Environmental toxinsGenital tract infection Quality of antenatal careEnvironmental toxinsQuality of antenatal care


vidual factors known to be associated with pretermbirth and intrauterine growth retardation (IUGR), thetwo major components of low birth weight.

Explanations based on the effects of poverty anddeprivation alone are insufficient to account for theobserved risk gradient. Fine grading of risk is evidentacross the whole socio-economic spectrum.

Neither do any of the risk factors shown in Table 3explain alone the social gradient. Many of the riskfactors, however, show a social gradient similar tobirth weight. Smoking in pregnancy follows a similarsocial gradient in Europe30 and the USA.31 Maternalheight,32 partly reflecting the mother’s own childhoodnutritional experience, young maternal age and highparity,33 genital infection,29 maternal ill health,34 obstet-ric complications29 and chronic stress35 all follow asimilar gradient.

The effects of these risk factors are likely to be addi-tive and cumulative over time.36 Biological vulnerabil-ity in later life37 and adult health behaviours seem tohave socio-economic roots early in life.38 The mother’sexperience of risk or protective factors as an infantand child will be carried forward into her pregnancyreflected in her weight, height and general healthstatus. Intergenerational disadvantage or advantagewill be reflected in her own birth weight and earlyillness experience. A woman whose own parents wererelatively disadvantaged is more likely to have beenlow birth weight herself, to have experienced morechildhood ill health, to have had a less nutritious dietwith adverse effect on her growth leading to relativestunting and anaemia, to have started smoking in ado-lescence and be less likely to quit in early pregnancyand to become pregnant at an earlier age.

The additive and cumulative effects of risk and pro-tective factors which are socially patterned over thelife course of women becoming pregnant provides thebasis of a plausible explanation for the social gradientin birth weight.

Child mental health and behaviour problems

A range of factors has been linked to mental healthproblems and behavioural difficulties in childhood.

Social factors such as poverty, housing conditions,unemployment and marginalization are linked toadverse child mental health outcomes. Other factorscorrelated with child mental health problems aresocially patterned. These include poor parentingskills,34 marital conflict,40 parent marital status,12

parental psychopathology,41 exposure to negative lifeevents,42 low IQ,24 academic failure,43 and racism.44

Protective factors such as positive peer relationships,social support, positive child–parent relationships anda positive school environment are also likely to beinfluenced by social determinants. These risk and pro-tective factors are likely to be additive and cumulativeover time. The lower the income of the family, themore likely the child is to be exposed to inadequatehousing, family unemployment and marginalization. Asimilar graded, cumulative exposure to poor parent-ing skills, negative life events, marital conflict, loneparent status, and academic failure is likely. Equally,the child is less likely to encounter protective factorsas the level of family disadvantage increases.

In summary, additive and cumulative risk and protec-tive factors, acting over time and between genera-tions, provide a plausible explanation for the finegrading of risk of birth weight and child mental healthproblems by social group.

Policy and researchimplicationsA considerable proportion of childhood ill health is sta-tistically attributable to social inequalities. Put anotherway, if all social groups had the same child health out-comes as the most materially privileged, the asso-ciated health gain would be huge in childhood andthroughout the life course. All societies would showhealth gain, but the effect would be greatest in themost unequal societies. Empirical evidence from lessdeveloped countries such as Cuba, Costa Rica andthe Indian state of Kerala1 and from comparisons ofindustrial countries with varying levels of income dis-tribution45 supports this contention. Nonetheless, eventhose countries with more equal income distributiondemonstrate social gradients in child health.20 This isconsistent with the accumulation of risk and protec-tion across generations and over time, indicating that



eradication of child health inequalities is likely to beachievable only in the long term.

The likely resistance of social gradients in child healthto short-term measures should not be used as areason for inaction. Social and economic policies thatincrease income inequality and push more familieswith children into relative poverty have been shown tolead to overall deterioration in the health of the childand adult population.46 The consequences of thesepolicies are manifest not only in ill health, but inincreased levels of antisocial behaviour and crime.46

Suicide and mental illness have increased, particularlyamong young men, and smoking and other behavioursdetrimental to health have become increasingly associated with material deprivation and marginalizedgroups.46 The legacy of the Thatcher/Reagan eco-nomic hegemony in ill health and loss of social cohe-sion is already huge and is likely to increase unlesskey social and economic policies are reversed.

The effectiveness of some health-related interven-tions, such as home visiting47 and early childhoodeducation,48 directed at alleviating or modifying a par-ticular risk factor contributing to the social gradienthas been shown. Given the explanations for the socialgradient outlined above, however, the effects of thesesingle factor interventions are likely to be small compared with the overall effects of adverse social,economic, and environmental conditions. Such inter-ventions are often targeted at the highest-risk groupson the basis that the efficacy is likely to be highest inthose most ‘at risk.’ On good theoretical grounds, itcan be argued that risk-based interventions are lesseffective than interventions aimed at changing the riskprofile of the whole population.49

Health-related interventions are most likely to con-tribute positively to the reduction in child healthinequalities if they are nonstigmatizing, nonvictimblaming, sensitive to the social and political context inwhich parents are rearing children, and set out toaddress a range of risk and protective factors as theyaffect populations, not just individuals.

Research related to ill health in children and adults is dominated by the biomedical paradigm. Hugeresources are expended in the pursuit of the bio-mechanisms underlying rare childhood conditions.Resources committed to research into the social and

environmental causes of childhood illness are smalland focused on individual risk factors. Interest in life-course epidemiology and the cumulative effects of risk has grown in recent years, but remains seriouslyunder-resourced, particularly as it applies to child-hood. We need to know more about the mechanismsby which risk factors combine, the critical periodsduring which their effects are greatest and the effec-tiveness of interventions directed at a complex of riskfactors rather than a single factor. If we are seriousabout the need to tackle health inequalities and toreduce the life-long handicap represented by a dis-advantaged childhood, research priorities will need tochange, and change quickly.

Framework for paediatriciansSocial, economic and political action is likely to be themost effective way to reduce inequalities in childhealth. Nonetheless, the paediatrician can play a roleat a number of levels. I have written more extensivelyabout this elsewhere.50 Here I set out a brief frame-work that paediatricians might use in contributing tothe reduction in child health inequalities.

Paediatricians as advocates

Paediatricians and their national and internationalorganizations can play a key role in influencing policymakers at local, national and international level.Advocacy can be used to highlight the impact of socialpolicies on child health. Up-to-date and relevant dataand political skills are essential to the success ofadvocacy. New political initiatives can be examined for their impact on child health using the methods ofhealth impact assessment. On a more mundane level,paediatricians may contribute to discussions aboutroad safety initiatives (or lack of them) in local areaswhere low-income children are particularly vulnerableto pedestrian accidents, or to the safety features oflow-cost or social housing. All paediatricians will befamiliar with the use of advocacy for individual fami-lies to assist them in obtaining a particular service oraid. The individual advocacy role is likely to be par-ticularly valuable for low-income families who are fre-quently disempowered in dealing with complex anddefensive bureaucracies.



Equity in health service delivery

There is good evidence that the ‘inverse care law’ con-tinues to operate to the disadvantage of low-incomefamilies and their children, even in child health ser-vices that are free at the time of use, such as the UKNational Health Service.51 Although this is mainly influ-enced by structural factors, paediatricians can takesteps to ensure equity in the services they offer. First, we can ensure that, as far as possible within the structure of the country’s health service, access to appropriate paediatric care is not dependent onincome. Second, we can ensure accessibility andacceptability of the service, with particular attention to the needs of children from low-income families. Third, we can provide flexible services designed tomeet the needs of low-income children. This mightinvolve the delivery of paediatric care in the home orin centres close to low-income areas. Finally, paedia-tricians should monitor the equity of their service regularly and introduce appropriate changes whennecessary.

Sensitivity to social context

In common with other doctors and many health pro-fessionals, paediatricians tend to be middle class andfrom high-income families. We need to be alert to thepossibility that our prejudices will influence the way wetreat low-income families. The key is for the paedia-trician, from whatever background, to be sensitive tothe social context in which families are living and tobe empathetic with the constraints imposed by socialand material deprivation. There are clearly limits toempathy and sensitivity, for example in the presenceof abuse or neglect, but in general, families are morelikely to participate actively in a child care partnershipif the social and environmental constraints are under-stood and accepted.

Conclusions• Many adverse child health outcomes show a finely

graded pattern of risk from the least to the mostdisadvantaged children.

• Reduced mean birth weight and impaired childmental health are two important examples withimplications for the life course.

• The cumulative and additive effects of risk and pro-tective factors are the most likely explanation forsocial gradients.

• Interventions aimed at modifying single risk fac-tors are likely to have limited influence on social gradients.

• Health and social policies addressing underlyingmaterial and social inequalities are likely to havethe greatest potential for modifying risk.

• Paediatricians have a role in advocacy and inensuring equality of access to their services.

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Correspondence: School of Postgraduate MedicalEducation and Department of Social Policy andSocial Work, University of Warwick, Coventry, CV4 7AL, UKTel: 0044(0)2476523167; Fax: 0044(0)2476524415;e-mail: [email protected]

Commentary

Spencer’s paper1 is a welcome and timely addition to the burgeoning literature on social inequalities inhealth. While the overall picture from the last decadesof the 20th century has been one of general improve-ments in health, there has been a growing recognitionthat not all members of the population have sharedequally in these health gains.2 In most rich countries,inequalities in health have actually widened over the last 50 years, and have become the specific sub-ject of much government-sponsored research. In theUnited States, understanding and reducing healthinequalities has been designated a priority area by thesurgeon general.3 While much past research hasbeen concerned with inequalities in adult health, thereis an increasing focus on inequalities in child health.The persistent socioeconomic, racial and ethnic dif-ferences in infant mortality and low birth weightremain an enduring public health concern in the US.The fact that health inequalities exist in childhood hasalso stimulated much interest into how early life expo-sures may influence subsequent disease processes.4

Even though paediatricians and other child health professionals have long been advocates for greateremphasis on improving health for the young, it is gratifying that inequalities per se are receivingincreasing research and policy attention. In fact,investments in reducing health differentials in early lifemay well be our best bet for longer-term reductions inthe overall burden of health inequalities in later life.

Spencer summarizes the broad scope of inequalitiesin child health that include congenital abnormalities,traumatic death, low birth weight, certain infections,suicide, mental health and risk behaviours. Inequali-ties in such a wide range of health outcomes shouldnot, however, be interpreted to mean that childrenfrom disadvantaged backgrounds have some inherentbiological ‘general susceptibility’ to poorer health.5

The basic rule for understanding why health inequal-ities are manifested is that social position (indicatedby factors such as education, income, race) structuresthe likelihood of exposure to the relevant risk and pro-tective factors for a particular outcome.6 This explainswhy children travelling in 3rd class on the Titanic hadhigher fatality rates than those in first class, who hadaccess to lifeboats. The effects of social position onstructuring risk exposures may also be temporallyspecific, as illustrated in Spencer’s example of howthe social distribution of polio changed after the intro-



duction of the vaccine. In this case, position in thesocial structure facilitated differential access to the relevant health protective factor. To a large extent,inequalities in child health exist because of the waywe design social systems and how those socialsystems influence the average levels and distributionof the risk and protective factors relevant to childhealth.

Spencer offers another important insight into un-derstanding health inequalities. He argues that thereis a socio-economic gradient in child health. Healthinequalities should not be framed as simply a pro-blem of a threshold in health between the rich andpoor. There is a graded association between socio-economic position and health in children, that is prob-ably best characterized as one of diminishing returns.While each step up the socio-economic ladder pro-duces gains in health, these gains are larger at thebottom of the ladder. For example, it is likely that a$1000 increase in available income buys more healthgain for disadvantaged children than for children fromwealthy backgrounds. Recognition of graded healthdifferences is important, but it is also important to recognize the difference between relative and ab-solute measures of inequality, and what these meanin terms of public health. Relative inequalities in childhealth exist across all levels of the socio-economicspectrum, i.e. child health differences can be ob-served between the most advantaged and the nextlevel down the socio-economic hierarchy, but at thetop of the social hierarchy, these differences can affecta relatively small number of children. We must keepin mind that in an absolute sense, the disproportion-ate burden of ill-health among children still falls on themost disadvantaged – that is, the social group fromwhich most cases arise. Relative risk indicators areuseful for aetiologic understanding, but public healthpolicy should be based on understanding the socialdistribution of absolute levels of disease burden.

This brings us back to a focus on the middle andbottom of the social hierarchy. How can we improvesocial conditions that will bring children from thesegroups up to a level of health enjoyed by children frommore advantaged backgrounds? I think it is veryinstructive to compare how different societies haveapproached such a question, and perhaps the bestevidence exists for how different countries treat theirmost disadvantaged children. While Spencer correctly

discusses the role paediatricians can play in ensuringequity of access to health care, he discusses thiswithin the context of the universal coverage offered bythe NHS in the UK. In the US we face a more funda-mental problem. More than 11 million children – 15.4%of the population aged 0–17 – have no health insur-ance coverage at all. Among children from homes withincomes less than 200% of the poverty level, this raterises to more than 25%.7

The UK and US are prime examples of nations where the world-wide rise in income inequality thatbegan in the late 1970s has resulted in largeincreases in child poverty.8,9 Other countries havebeen less willing to allow the burdens of increasingincome inequality to fall on the youngest members ofthe society. A recent report cogently demonstratedthat child poverty – surely the most important sourceof postnatal health inequalities – is not an inevitableconsequence of market forces and globalization.UNICEF’s Innocenti Report Card10 released in June,2000 is worthwhile reading for anyone interested inunderstanding how the policy choices we make helpdetermine how much child poverty exists in a countryand, to a large extent, the extent of child healthinequality. The report presents several striking facts:

• In the UK and US, relative child poverty (definedas households with incomes below 50% of thenational average) is 20 and 22%, respectively. InSweden and Norway it is 2.6 and 3.9%.

• Differences in the proportion of lone-parent house-holds has little to do with child poverty rates, butthe amount of poverty in those lone-parent familiesdoes. In the UK and US 46% and 55% of lone-parent households are in poverty, while in Swedenthe percentage is 7%; Denmark, 14%; The Nether-lands, 24%; Australia, 36% and Canada, 52%.

• In the UK it is a combination of lone-parent fami-lies, unemployment and low wages that make thegreatest contributions to child poverty. The samelist holds for the US, but in addition to this are theeffects of low social welfare expenditures thatoffset market-generated inequality.

• For the UK and US, it would take just 0.48 and0.68% of GNP to bring all households with childrencurrently in poverty up to the poverty line. Whileour goal would be to raise all households with children well above the poverty threshold, thesefigures suggest the problem of child poverty is farfrom economically insurmountable.



While this UNICEF report focuses on relative childpoverty, I nevertheless think it offers insights into howchildren across the socio-economic spectrum in thesesocieties are treated. For practical reasons, it focusesspecifically on ‘income poverty’, but we should alsokeep in mind the seminal writings of the Nobel Prizewinning economist Amartya Sen, who has argued thatpoverty is a multidimensional concept that really rep-resents a range of resources, capabilities, functionsand opportunities that enable children to fully partici-pate in their society and share its benefits.11 One ofthese benefits is the level of health a society gener-ates. Inequalities in child health reflect the biologicaland social inheritance from previous generations, as well as the current social conditions imposed onthe growing child. At least up until adolescence, therecan be no hint of victim-blaming for child healthinequalities, as is a popular interpretation of adulthealth inequalities. Children do not generate theirpoorer health by drinking, smoking and staying out late. In the case of child health inequalities, thereare only young victims of the social conditions adultsgenerate.

Biosketch: Dr John Lynch is an epidemiologisttrained in Australia and the University of California atBerkeley. He is an Assistant Professor of Epidemiol-ogy at the University of Michigan School of PublicHealth. He has published extensively in the field ofhealth inequalities. His research focuses on under-standing the inter- and intragenerational life courseprocesses that generate health inequalities.

References

1 Spencer N (2000) Social gradients in child health: whydo they occur and what can paediatricians do about them?Ambulatory Child Health, 6: 191–202.

2 Marmot M and Wilkinson R G, eds. (2000) The Social Determinants of Health. Oxford University Press,Oxford.

3 Kuh D and Ben Shlomo Y, eds.www.surgeongeneral.gov/myjob/priorities.htm

4 Kuh D and Ben Shlomo Y, eds. (1997) A LifecourseApproach to Chronic Disease Epidemiology. Oxford Uni-versity Press, Oxford.

5 Najman J M and Davey Smith G (2000) The embodi-ment of class-related and health inequalities: australianpolicies. Australian and New Zealand Journal of PublicHealth, 24: 3–4.

6 Lynch J W and Kaplan G A (2000) SocioeconomicPosition. In: Berkman L F and Kawachi I, eds. Social Epi-demiology. Oxford University Press, New York; pp. 13–35.

7 US and Census Bureau (1998) Health Insurance Cov-erage. www.census.gov/hhes/hlthins/hlthin98.html

8 Bradbury B and Jantti M (1999) Child Poverty AcrossIndustrialized Nations. LIS Working Paper 205, September.

9 Shaw M, Dorling D, Gordon D and Davey Smith G(1999) The Widening Gap. The Policy Press, Bristol.

10 UNICEF Innocenti Research Centre. (2000) InnocentiReport Card no. 1. A League Table of Child Poverty in RichNations. Florence, Italy, June. www.unicef-icdc.org/new

11 Sen A (1992) Inequality Reexamined. Harvard Univer-sity Press, Cambridge, MA.


social gradients in child health: why do they occur and what can paediatricians do about them?

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