Dependent Interviewing: Seminar, University of Essex September 2004 Peter Shepherd Centre for Longitudinal Studies, Institute of Education, University of London Birth Cohort Studies National Child Development Study, 1970 British Cohort Study, Millennium Cohort Study

Birth Cohort Studies National 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 British Cohort Study (BCS70) All those living in GB born in one week in 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

Birth Cohort Studies – Main surveys Age of cohort members at time of main surveys

Goals of Birth Cohort Studies  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.

Why cohort studies are important Expensive compared to cross-sectional surveys, but are important because:  They tell the linked stories of the lives of the members  They record how long someone occupies a given state  They link events across the life course & across domains  They enable investigation of the cause & effects, early experience to later outcomes

Life course Perspective  Holistic  Transitions & pathways  Interconnectedness  Linked lives

Design Principles  Continuity & comparability  Age, cohort & period effects  Spatial effects  Consultation  Harmonisation  Life course perspective

MCS - Design Features  Cohort born over 12 month period  Season of birth effects  Spread workload of professional interviewers  Sampling necessitated  Geographically clustered by electoral ward Wards disproportionately stratified - 3 types: advantaged; disadvantaged 1 ; and high minority ethnic 2  Content multi-purpose & multidisciplinary 1 Poorest 25% of wards on Child Poverty Index. 2 At least 30% of 1991 Census ward population = 'Black‘/'Asian‘ – England only.

MCS – Sweeps & sources of information Includes c500 ‘new families’ missed by DWP at MCS1

MCS1 – Achieved samples NB: Wards vary in births/12 months (4-600). To minimise fieldwork problems, small wards combined as 'superwards' with at least 24 expected births/12 months.

MCS1 - Response Rates Achieved Response Rate In-scope Fieldwork Response Rate WALES72%84% ENGLAND68%82% SCOTLAND70%85% NORTHERN IRELAND 63%79%

MCS1 & 2 - Main/Partner Topics MCS1 MCS2 (including c500 ‘new families’) more…

Cohort studies - Why use dependent interviewing With thanks to: Mathiowetz Nancy A. and McGonagle Katherine A. (2000) An assessment of the current state of dependent interviewing in household surveys Journal of official statistics 16 pp

MCS2 - Feed forward/Dependent interviewing

MCS2 – Use of feed forward 1

MCS2 – Use of feed forward 2

MCS2 – Use of feed forward 3

NCDS - Follow-ups & information sources Exams – details of public examination results were gathered from schools and colleges in 1978 Information gathered includes:  Health  Behaviour  Family  Education  Employment  Attitudes Information gathered includes:  Health  Behaviour  Family  Education  Employment  Attitudes

BCS70 - Follow-ups & information sources Information gathered includes:  Health  Behaviour  Family  Education  Employment  Attitudes Information gathered includes:  Health  Behaviour  Family  Education  Employment  Attitudes

BCS70/NCDS 2004: Feed forward/Dependent interviewing

Cohort Studies - Websites for further information MCS: BCS70: NCDS: ESDS Longitudinal: UK Data Archive:

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