Finding and analysing variables in the CLS cohorts Brian Dodgeon Centre for Longitudinal Studies Institute of Education University College London

Introduction to the UK Birth Cohorts

Five national birth cohort studies: 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 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 & Wales, and December 2000 in Scotland & Northern Ireland Life Study ( ) Pregnant women recruited at ~28 th week from those planning to deliver at one of 23 UK maternity units, and a nationally representative clustered sample of UK births – a total of 80,000 babies born between 2014 and CLS - based

Early childhoodMid childhoodEarly adulthoodEarly middleLate middle (0-5)(6-16)(17-30)adulthood (31-50)(51-65) NSHD (1946) Ages surveyed0, 2, 46, 7, 8, 9, 10, 11, 13, 1519, 20, 22, 23, 25, 2631, 36, 4353, 54, 65 NCDS (1958) Ages surveyed07, 11, , 42, 46, 5055, (60) BCS70 (1970) Ages surveyed0, 510,1626, 3034, 38, 42, (46) MCS (2000) Ages surveyed9 months, 3, 57, 11, 14 Life Study (2014) Ages surveyed4 and 12 months* British Birth Cohorts: from Childhood to Adulthood

NCDS: National Child Development Study  Origins in ‘Perinatal Mortality Survey’ to examine social & obstetric factors re stillbirth and death in early infancy (n=17,415 born GB in one week 1958)  Survivors followed at ages 7, 11, 16, 23, 33, 42, 46, 50, 55 (next at 60)  ‘Immigrants’ identified in schools included at 7,11 and 16  Information gathered from multiple sources  Multipurpose study: family life; education; employment; skills; housing; health; finances; etc.  About 12,000 still participating  Now funded by ESRC with data collected every four/five years

BCS70: 1970 Birth Cohort Study  Origins in ‘British Births Survey’ (n=17,198 born GB in one week 1970)  Survivors followed at ages 5, 10, 16, 26, 30, 34, 38, 42 (next at 46)  ‘Immigrants’ identified in schools included at 5 and10  Information gathered from multiple sources  Multipurpose study: family life; education; employment; skills; housing; health; finances; etc.  About 12,000 still participating  Now funded by ESRC with data collected every four years  Co-ordination with NCDS facilitates cross cohort comparisons

MCS: Millennium Cohort Study  Origins in ESRC review on resource needs  Cohort born over 12 month period (n=>18,800)  Season of birth effects  Spread workload of professional interviewers  Sampling necessitated  Geographically clustered by UK electoral ward in UK, disproportionately stratified - 3 types:  advantaged  disadvantaged  high minority ethnic  Multipurpose & multidisciplinary  Surveys at 9 months, 3, 5, 7, 11, 14 years  Funded by ESRC and a consortium of government departments

Centre for Longitudinal Studies (CLS) – what does it do?  CLS responsible for birth cohort studies since 1985  Became ESRC-funded Resource Centre in 2004, responsible for conservation, development & dissemination of the Studies  Data collection –  Develop survey content, consult academics & policy makers  Brief and supervise a fieldwork agency to do interviews  Keep track of where cohort members are – via tracing team and admin registers  Produce fully-documented datasets:  Available via UK Data Service  Enhance data by producing derived variables  Provide access to non-computerised data  Help Users  Documentation: Working papers/Data Notes  Training Workshops  Advice & Guidance by & phone

HYPOTHETICAL LIFE HISTORY x Born st Child nd Child 1987 Age 7 Age Age Age 46 Age 16 Age Age 33 Gets married Parents’ social class Parental interest in school work Free school meals Mother smoking Parental divorce Maths and reading tests Teachers’ assessment of child’s behaviour Exam results Job 1Job 2Job 3 Voting behaviour Psychological well being Working hours preferences Savings Domestic division of labour Union membership Training and skills

BCS70 follow-ups and information sources

BCS70: at what ages do we learn about speech difficulties?  Age 5  Home Interview Questionnaire  section B: Medical History and Present Health  Age 10  Parental Interview  Medical Examination  Age 16  Maternal Self-Completion  Educational (Teacher's) Questionnaire

BCS70: speech difficulties at age 5  Age 5  Home Interview Questionnaire (section B: Medical History and Present Health)  E104 Ever had stammer or stutter?  E105 Ever had other speech difficulty?  E106 Speech understood by others?

BCS70: speech difficulties at age 5  Age 5  Home Interview Questionnaire (section B: Medical History and Present Health)  E104 Ever had stammer or stutter?

BCS70: speech difficulties at age 5  Age 5  Home Interview Questionnaire (section B: Medical History and Present Health)  E105 Ever had other speech difficulty?

BCS70: speech difficulties at age 5  Age 5  Home Interview Questionnaire (section B: Medical History and Present Health)  E106 Speech understood by others?

BCS70: speech difficulties at age 10  Age 10  Parental Interview  B20.1 Has child ever been to speech therapist  B20.2 Reason child been to speech therapist  Medical Examination  MEA9.14 Reason for attending speech therapist  MEB Speech test sentence  MEB15.1 How intelligible is child’s speech?  MEB16 Does child stammer or stutter?

BCS70: speech difficulties at age 10  Age 10  Parental Interview  B20.1 Has child ever been to speech therapist  B20.2 Reason child been to speech therapist

BCS70: speech difficulties at age 10  Age 10  Medical Examination  MEB Speech test sentence  MEB15.1 How intelligible is child’s speech?  MEB16 Does child stammer or stutter?

BCS70: speech difficulties at age 16  Age 16  Maternal Self-Completion  PA2.1 Has your teenager any present or past difficulty with speech?  PA2.2 Was it a severe stammer?  PA2.3 Was it a slight stammer?  PA2.4 Can’t say words properly?  PA2.5 Othyer type of speech difficulty?  Educational (Teacher's) Questionnaire  L14.5 Pupil appears to have stammer or stutter

BCS70: speech difficulties at age 16  Maternal Self-Completion  PA2.1 Has your teenager any present or past difficulty with speech?  PA2.2 Was it a severe stammer?  PA2.3 Was it a slight stammer?

BCS70: speech difficulties at age 16  Maternal Self-Completion  PA2.4 Can’t say words properly?  PA2.5 Other type of speech difficulty?  Educational (Teacher's) Questionnaire  L14.5 Pupil appears to have stammer or stutter