Www.cls.ioe.ac.uk ESDS Longitudinal: Introducing the UK cohort and birth studies Peter Shepherd 21 June 2004 National Child Development Study and 1970.

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ESDS Longitudinal:

Introducing the UK cohort and birth studies

Peter Shepherd

21 June 2004

National Child Development Studyand 1970 British Cohort Study

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Birth Cohort StudiesNational Survey of Health and Development (NSHD)

Those living in GB born in one week in 1946

National Survey of Health and Development (NSHD)Those living in GB born in one week in 1946

National Child Development Study (NCDS)All those living in GB born in one week in 1958

National Child Development Study (NCDS)All those living in GB born in one week in 1958

1970 British Cohort Study (BCS70)All those living in GB born in one week in 1970

1970 British Cohort Study (BCS70)All those living in GB born in one week in 1970

Millennium Cohort Study (MCS)All those born in selected areas of UK over 12 months

beginning September 2000 in England and Wales, and December 2000 in Scotland and Northern Ireland

Millennium Cohort Study (MCS)All those born in selected areas of UK over 12 months

beginning September 2000 in England and Wales, and December 2000 in Scotland and Northern Ireland

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Birth Cohort Studies - 2

Notes1 Initial survey carried out at c8 weeks2 Initial survey carried out at c9 months(Age) Sample surveys

Age of cohort members at time of main surveysAge of cohort members at time of main surveys

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National Child Development Study - NCDS

17,415 individuals born in a week in GB in 1958

Follow-up of whole sample

12,000 still participating

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1970 British Cohort Study - BCS70

16,571 individuals born in a week in GB in 1970

Follow-up of whole sample

12,000 still participating

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Goals of Longitudinal Study Modelling causal processes from birth to adulthood leading to current

outcomes and assessing the risk of future outcomes.

Assessing the stability of hypothesised causal processes across cohorts.

Comparing the prevalence of behaviour and attributes across cohorts, ages and periods.

Assessing inter-generational continuities and discontinuities in circumstances, behaviour and attributes.

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Design Principles Continuity & comparability

Age, cohort & period effects

Spatial effects

Consultation

Harmonisation

Life course perspective

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Life course Perspective

Holistic

Transitions & pathways

Interconnectedness

Linked lives

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Data Specification Parameters

Identify key variables representing different elements of life course in and across life domains.

Find the optimum way to operationalise these via survey questions and other measures.

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NCDS Follow-ups & information sourcesP M S N C D S 1 N C D S 2 N C D S 3 N C D S 4 N C D S 5 N C D S 6

( 1 9 5 8 ) ( 1 9 6 5 ) ( 1 9 6 9 ) ( 1 9 7 4 ) ( 1 9 8 1 ) ( 1 9 9 1 ) ( 2 0 0 0 )B i r t h 7 1 1 1 6 2 3 3 3 4 2

1 7 , 7 3 3 a 1 6 , 8 8 3 1 6 , 8 3 5 1 6 , 9 1 5 1 6 , 4 5 7 1 5 , 6 0 0 1 5 , 1 4 5

M o t h e r — P a r e n t s — P a r e n t s — P a r e n t s

S c h o o l — S c h o o l — S c h o o l

T e s t s — T e s t s — T e s t s

M e d i c a l — M e d i c a l — M e d i c a l — M e d i c a l

S u b j e c t — S u b j e c t — S u b j e c t — S u b j e c t — S u b j e c t — S u b j e c t

C e n s u s — C e n s u s

S p o u s e / P a r t n e r

M o t h e r c

C h i l d r e n

1 7 , 4 1 4 b 1 5 , 5 6 8 1 5 , 5 0 3 1 4 , 7 6 1 1 2 , 5 3 7 1 1 , 4 0 7 1 1 , 4 1 9

}

1 i n 3 s a m p l e

N C D S 7( 2 0 0 4 )

4 6

1 2 , 8 0 0

— S u b j e c t

?

}

1 i n 3 s a m p l e

Exams – details of public examination results were gathered from schools and colleges in 1978

Exams – details of public examination results were gathered from schools and colleges in 1978

Information gathered includes:HealthBehaviourFamilyEducationEmploymentAttitudes

Information gathered includes:HealthBehaviourFamilyEducationEmploymentAttitudes

Notesa: Target sample - Excludes emigrants, refusals & deaths. Includes immigrants at NCDS1-3.b: Achieved sample - At least on survey instrument partially completedc: Mother - Could be Cohort Member or spouse/partner

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BCS70 Follow-ups & information sources

BBS CHES CHES Youthscan BCS70 BCS70(1970) (1975) (1980) (1986) (1996) (2000)Birth 5 10 16 26 30

Mother — Parents — Parents — Parents

School — School

Tests — Tests — Tests

Medical — Medical — Medical — Medical

Subject — Subject — Subject — Subject

16,135a 13,135 14,875 11,628 9,003 11,261

BCS70(2004)

34

— Subject

Children (1 in 2 sample)

?

Notesa: Achieved sample. NB: Target sample excluded emigrants, refusals & deaths; and included immigrants in 1975 & 1980.

Information gathered includes:HealthBehaviourFamilyEducationEmploymentAttitudes

Information gathered includes:HealthBehaviourFamilyEducationEmploymentAttitudes

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Data coverage - Childhood

What type of person is the child becoming? Development – physical & cognitive Medical assessments

growth respiratory functioning sexual development

Cognitive assessments Maths Reading Writing etc.

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Data coverage - Adulthood

What type of adult has the cohort member become and how did they get there? Current states Household Partnerships Family formation Housing Education Labour market & income Health Citizenship & values

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MethodsVariety of data collection methods used:

Face to face interviews (Paper/CAPI) Proxy interviews Telephone Interviews Self completions (Paper/CASI) Assessments Medical measurements

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NCDS FundingPMS: National Birthday Trust Fund. 

NCDS1: Department of Education & Science. 

NCDS2: Social Science Research Council. 

NCDS3: Department of Education & Science and Department of Health & Social Security. 

NCDS4: Department of Health & Social Security; Department of Education & Science; Department of Employment; Manpower Services Commission; and Department of the Environment. 

NCDS5: Economic and Social Research Council; Department of Health; Department of Social Security Employment Department; Department of Education and Science; Department of the Environment; Transport and Road Research Laboratory; Health and Safety Executive; and US National Institute of Child Health and Development. 

NCDS6: Economic and Social Research Council; Government Departments and Agencies (Office of National Statistics, Department for Education and Employment, Department of Social security, Department of Health, Scottish Executive, Basic Skills Agency); and the International Centre for Child Studies.

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BCS70 FundingBirth: Royal College of Obstetricians & Gynaecologists; Marks and Spencer; Glaxo; Pergamon Press; and Department of Health and Social Security. 

Five: Medical Research Council; Economic and Social Research Council; National Birthday Trust; Action Research for the Crippled Child; Leverhulme Trust; and other charitable trusts. 

Ten: Rowntree Memorial Trust; Department of Education and Science; Department of Health and Social Security; Manpower Services Commission; and US National Institute of Child Health and Development. 

Sixteen: Home Office; Cancer Research Campaign; Beechams; Kellogg’s; Westland; HTV; Channel 4; Allied Lyons; WT Grant Foundation; Sir J Knott Settlement; Hayward Foundation; Daily Star; New Moorgate Trust; Lankelly Foundation; Laura Ashley Trust; other public and private bodies; and private donations. 

Twenty-six: Economic and Social Research Council. 

Thirty: Economic and Social Research Council; Government Departments and Agencies (Office of National Statistics, Department for Education and Employment, Department of Social security, Department of Health, Scottish Executive, Basic Skills Agency); and the International Centre for Child Studies.

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NCDS – 2004 SweepTelephone Interview• Housing• Partnerships – current and former• Births and other pregnancies• Periods of lone parenthood• Absent children• Children and the wider family• Family income • Employment status/employment history• Academic education/vocational training/other courses• Access to and use of computers• Basic skills• General health• Smoking. Drinking and exercise• Experience of crime• Social participation• Identity

Postal questionnaire for those who cannot be interviewed on ‘phone

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BCS70 – 2004 SweepCORE: All CMs

Interview (CAPI) - updating social, economic, health info 

Self-completion (CASI) - attitudes, family life, drinking, skills, well-being, crime 

Adult assessments (CAPI/CASI/Paper) - functional literacy, numeracy, dyslexia

PARENT & CHILD: CMs with resident natural/adopted child aged <17  

Parent Interview (CAPI) - age specific (0<17) childcare, health & schooling, etc 

Parent Self-completion (Paper) - age specific questions on development, relationships, behaviour, discipline, school absence/exclusion, reading & schoolwork  

Child assessments (CAPI/Paper) - age specific (3<17) assessments of naming, copying, reading, spelling, number 

Child (10<17) self-completion (Paper) - leisure, relationships, school, the future drugs, crime, self-esteem

In a1 in 2

sample

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BCS70 - 2004 SweepCORE: All Cohort Members 

Interview (CAPI):• Housing• Partnerships – current and former• Births and other pregnancies• Periods of lone parenthood• Children and the wider family• Family income • Employment status/employment history• Academic education• Vocational training• Access to and use of computers• Basic skills• General health• Diet and exercise• Height and weight• Family activities, social participation, social support

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BCS70 - 2004 SweepCORE: All Cohort Members 

CASI self-completion• Political attitudes• Family life• Drinking• General skills• Psychological well-being• Experience of crime

Adult assessments• Basic skills (literacy and numeracy) questions in multiple choice format (CASI/CAPI)• Basic skills (literacy and numeracy) questions in an open-response format (CAPI)• Reading/writing exercises (adapted from the Dyslexia Adult Screening Test)• Short written task

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BCS70 - 2004 SweepPARENT & CHILD: CMs with resident natural/adopted child aged <17

Parent Interview (CAPI)Age specific questions on:

• Child’s physical and mental health• Mother’s health-related behaviour during pregnancy• Parent-child separations• Pre-school care• Current education• Parental aspirations• Consent for child assessments

In a1 in 2

sample

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BCS70 - 2004 SweepPARENT & CHILD: CMs with resident natural/adopted child aged <17

Parent Self-completion (Paper)Age specific questions on:• Physical and cognitive development • Parent/child relationship• Child’s behaviour and how s/he relates to other children and adults • Disciplining children • School absence/exclusion • Reading and schoolwork.

In a1 in 2

sample

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BCS70 - 2004 SweepPARENT & CHILD: CMs with resident natural/adopted child aged <17

Child assessmentsAge specific (3<17) assessments:

Early Years (3:0 – 5:11)• BAS Naming Vocabulary• BAS Early Number Concepts• Copying

School Age (6:0 – 16:11)• BAS Word Reading• BAS Spelling• BAS Number Skills

In a1 in 2

sample

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BCS70 - 2004 SweepPARENT & CHILD: CMs with resident natural/adopted child aged <17Child (10<17) Self-completion (Paper) 

• Leisure time• Relationship with their parents• Attitudes to school and aspirations for the future• Smoking, drinking, drug use and experience of petty crime• Self-esteem

In a1 in 2

sample

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The Future

Complete cohort follow-ups every 8 years alternating NCDS/BCS70: next round BCS70 in 2004 including a basic skills assessment of all cohort members and inter-generational family study involving 1 in 2 cohort members and their children

Telephone follow-up every 4 years: next round NCDS in 2004

Sub-sample follow-ups: biographical studies of selected cohort members

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NCDS – Surveys of sub-samples

NCDS:

Children in Care (1965) Epilepsy (1979, 1986)

Adopted Children (1967, 1973) Causes of deaths (1982)

Gifted Children (1969) Successful Disadvantaged (1985)

Children of Lone Parents (1973) Mothers and Children (1991)

Handicapped School Leavers (1976) Respiratory Health (1993)

Feasibility Study for NCDS4 (1978) Crohn’s Disease (1994)

Smoking (1978) Basic Skills Problems (1995)

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BCS70 - Surveys of sub-samples

British Births Child Survey (all twins, low birth-weight & post-mature births, and a 10% random sample of the original cohort), 1972/3

South West Region Survey (95% of the cohort members living in the south west of England or Glamorgan, South Wales), 1972/3

Nursery and Playgroup Survey, 1975

Non-respondents to 5-year survey, 1977

Transition school to work and basic skills problems, 1992

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NCDS Biomedical Survey 2002-2004

(In collaboration with: Institute of Child Health; St George's Hospital Medical School; National Centre for Social Research; and others)

To obtain objective measures of ill-health/biomedical risk

• Standing & sitting height, weight, waist & hip• Blood pressure & pulse rate• Ventilatory function - FEV1 & FVC• Blood collection for lipids, glycosylated haemoglobin, total & specific IgE, DNA extraction • Near (reading) and distant (2m) vision, stereopsis and refractive error • Pure tone audiometry at 2 frequencies• Psychiatric diagnostic interviews: CIS-R  • Saliva collection for early-morning cortisol level

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NCDS Parents

(In collaboration with Institute of Child Health)

“Morbidity and mortality in 2 generations.”

Examine the influence of indicators of health and growth in one generation on the health and growth of the preceding or subsequent generation

Supplement existing survey data on parental height and morbidity by:

• Identifying NCDS parents on NHSCR

• Receiving vital event data on death and cancer registration

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NCDS Qualitative – Basic Skills(In collaboration with National Research and Development Centre for Adult Basic Skills)

Life history interviews with c100 CMs identified through self-assessment/ testing as having basic skills difficulties but not necessarily taken coursesInterviews centred on:• Basic skills needs & aspirations• Life course events & demands • Awareness of ABE policy, publicity & provision• Participation in formal provision• Informal resources & support networks relating to basic skills• Practical engagement with literacy tasks• Informal & collective acquisition of literacy/numeracy skills & events which prompt such learning• Interaction of print literacy & other media usage, especially new communications technologies

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NCDS Qualitative – Asset effect(In collaboration with the Institute for Public Policy Research (IPPR) and the Centre for Analysis of Social Exclusion (CASE) at LSE)

Explore the importance of financial assets in improving people’s life chances and removing barriers to opportunity

Builds on earlier NCDS research that found positive relationships between asset holding at 23 and labour market performance, household stability, mental and physical health and some measures of citizenship at 33.

Bynner J and Paxton W (2001) The asset-effect London: IPPR

Bynner J and Paxton W (2001) The asset-effect London: IPPR

Quantitative - Econometric modelling of data to age 42

Qualitative - Research the life histories of CMs in more detail and to discover how they accumulated and used their assets over time, in order to try and answer what it is about holding an asset which leads to positive welfare outcomes

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Publications

Many hundreds of publications -list (of those we know about) on CLS website:

http://www.cls.ioe.ac.uk/Recently published - compares ’46, ’58 and ’70 Cohorts

Recently published - compares ’46, ’58 and ’70 Cohorts

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Findings – Independent of other influences

• Mothers who smoke during pregnancy are more likely to have low birth weight babies and, by age 16, these children are smaller and do worse at reading and maths. 

• Truancy and poor school attendance are connected to problems in adult employment and marital breakdown. 

• Being breast fed as a baby can reduce the risk of heart disease in adult life. 

• Children whose parents separate and who grow up in poverty are often poor at maths, and are more likely to leave school early and marry in their teens. 

• Long working hours and job insecurity are making life much harder for families now than in the past, especially where the father is working more than 50 hours a week. 

• The more interest parents show in their children’s education, the better the children do in school. 

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Findings 2 – Independent of other influences

• Those growing up in poor home circumstances often develop asthma and chronic bronchitis as adults. 

• Poor economic conditions at birth can disadvantage people in their subsequent employment and depress their adult incomes, but with the right support many do much better than expected 

• Education and training make a difference. Those with ‘O’ levels earn 7 per cent more than those with no qualifications. A degree can be worth 25 per cent more. Work related training boosts earnings by 12 per cent. 

• Stepfathers are just as involved with their step-children as other fathers. 

• Adults with poor basic skills are more likely to have grown up with parents who did not read stories to them or show interest in their educational progress.

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Constraints

Funding

Respondent burden

Reconciling different interests

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Methodological Issues

Measurement: fading relevance,validity and reliability

Attrition and bias

Question level non-response

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Bias Age Target% Achieved% %Bias

NCDS Gender (Male respondents)

na 51.2 49.2 -3.9

Ethnicity (Child's ethnic group is Afro-Caribbean)

16 1.1 0.6 -45.5

Social Class (Father's Social Class – Manual)

7 66.5 65.0 -2.3

Reading (Low Reading score)

11 20.0 16.9 -15.5

Poverty (Child receives free school meals)

16 10.2 8.6 -15.7

Tenure (Tenure - Private rented)

11 7.7 7.0 -9.1

BCS70 Gender (Male respondents)

na 51.1 45.6 -10.8

Ethnicity (Child's ethnic group - West Indian)

5 1.0 0.7 -30.0

Social class (Father’s social class – Manual)

5 63.1 60.2 -4.6

Reading (Great difficulty with reading)

10 3.1 2.4 -22.6

Poverty (Family receives Supplementary Benefit)

16 11.2 9.6 -14.3

Tenure (Accommodation rented privately)

10 3.0 2.7 -10.0

Notes: %Bias=(Achieved%-Target%)/Target%x100

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Differential response

NCDS1 NCDS2 NCDS3 Parental Interview 14,746 13,879 11,691 Medical Questionnaire 14,398 13,207 11,675 Educational Questionnaire 15,414 14,205 12,762 Any of above 15,414 15,303 14,761

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Changes in populations and samplesESRC Project: ‘Towards Quality Profiles for NCDS & BCS70’(Ian Plewis, Gad Nathan, Lisa Calderwood and Denise Hawkes

Cohort Studies Working Paper 

1.     Defining the populations.

2.     Non-response and response rates.

3.     Patterns of response.

4.     Domain response.

5.     Cross-sectional response rates.

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Longitudinal and cross-sectional samplesLongitudinal target sampleAll children born (alive or dead) in GB in the reference week until they die or permanently emigrate from GB 

Cross-sectional target sampleAll children born anywhere in the reference week living in GB at the time of each sweep 

NCDS

SWEEP PMS NCDS1 NCDS2 NCDS3 NCDS4 NCDS5 NCDS6Longitudinal 17,415 15,051 14,757 13,917 12,044 10,986 10,853Cross-sectional 0 517 746 844 493 421 566Total 17,415 15,568 15,503 14,761 12,537 11,407 11,419

BCS70

SWEEP Birth Five Ten Sixteen Twenty-six ThirtyLongitudinal 16,571 12,979 14,349 11,206 8,654 10,833Cross-sectional 0 156 526 422 349 428Total 16571 13135 14875 11628 9003 11261

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Acquiring NCDS/BCS70 data

UK Data Archive (UKDA)

Economic and Social Data Service

Centre for Longitudinal Studies

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Centre for Longitudinal Studies

Bedford Group, Institute of Education, University of London

Access to non-computerised data

Advice & guidance

Workshops/Seminars

Information on uses of the data/publications/ other developments

(Design; data collection/analysis; cohort maintenance)

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Documentation/Working papers/Data Notes

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NCDS/BCS70 DocumentationA variety of NCDS/BCS70 documentation is available, including:

Guides to datasets

Lists of publications

Annotated questionnaires

Interactive Data Dictionaries

‘Data Notes’ Other survey‑related documentation

Working papers, etc

Copies available from CLS / UK Data Archive

IMPORTANTAlways consult

documentation before selecting/analysing NCDS/BCS70 data

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Questionnaires

NCDS questionnaires:

http://www.cls.ioe.ac.uk/Cohort/Ncds/Documentation/maindocs.htm

BCS70 questionnaires:

http://www.cls.ioe.ac.uk/Cohort/Bcs/Document/maindoc.htm

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Data not available via the UK data Archive

Archive data updated:

After major data collections

Between data collections, as and when resources permit Between updates new/revised data/ derived variables made available to users via CLS

Additional data are the outcome of further minor data

collections; data cleaning; and insights gained from data analysis

Details from CLS (web/Data Notes)

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NCDS/BCS70 - HELP!

USER SUPPORT GROUP

+44 (0)20 7 612 6860

[email protected]

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