Cohort Descriptives

Variable Response
Cohort name MRC National Survey of Health & Development
Cohort acronym MRC NSHD
General Study Overview The MRC National Survey of Health and Development (MRC NSHD) has informed UK health care, education and social policy for more than 50 years and is the oldest and longest running of the British birth cohort studies. Today, with study members in their seventies, the NSHD offers a unique opportunity to explore the long-term biological and social processes of ageing and how ageing is affected by factors acting across the whole of life. From an initial maternity survey of births recorded in England, Scotland and Wales during one week of March, 1946, a socially stratified sample of singleton babies born to married parents was selected for follow-up. These participants have been studied over twenty times throughout their life.
During their childhood, the main aim of the NSHD was to investigate how the environment at home and at school affected physical and mental development and educational attainment. During adulthood, the main aim was to investigate how childhood health and development and lifetime social circumstances affected their adult health and function and their change with age.
Now, as participants reach retirement, the research team is developing the NSHD into a life course study of ageing. Study members were asked to attend a clinic at age 60-64 for a range of assessments (or alternatively have a home visit).. They were invited for a home visit at 69 years , updating information on health, lifestyle and life circumstances as well as obtaining repeat physical and cognitive measurements. Postal questionnaires were completed before the clinic and home visits. A subset of 500 study members are also being invited to participate in a Neuroscience sub-study.
Please note, alternatively, NSHD may be called the '1946 British birth cohort study' once the full name has been used first in any article.
Number of subjects at baseline 5,362
Institution name University College London
Department name MRC Unit for Lifelong Health and Ageing at UCL
City London
Study or database website

http://www.nshd.mrc.ac.uk/

Principal Investigator (PI): Name Nishi Chaturvedi
PI: Address MRC Unit for Lifelong Health and Ageing at UCL, National Survey of Health & Development, 33 Bedford Place London, WC1B 5JU
PI: email

n.chaturvedi@ucl.ac.uk

PI: phone +44 (0)20 7594 3381
Administrative Contact (AC): Name Andy Wong
AC: Address MRC Unit for Lifelong Health and Ageing at UCL, National Survey of Health & Development, 33 Bedford Place London, WC1B 5JU
AC: email Mrclha.swiftinfo@ucl.ac.uk
AC: phone +44(0) 20 7670 5709
Technical Contact/Data manager (TC): Name Marcus Richards
TC: Address MRC Unit for Lifelong Health and Ageing at UCL, National Survey of Health & Development, 33 Bedford Place London, WC1B 5JU
TC: email

m.richards@ucl.ac.uk

TC: phone +44 (0)20 7670 5710
Key study references

Open literature list

Population based study? Yes
Family based study? No
Clinical based sample? No
Is there follow-up data available? Yes
Were participants included prior to development of dementia (may refer to controls only)? Yes
Were participants included prior to development of MCI (may refer to controls only)? Yes
How is data collected? In person
postal
combination: Also in school
Who carries out data collection? Interviewers: Health visitors in childhood interviewed mothers. Research nurses interviewed study members in adult life. School doctors and teachers assessed the study members in childhood.
Does this take place in participants' homes or at a central location? Home
Central: Mothers took children to school doctors and clinics. Study members were invited to Wellcome Trust Clinical Research Facilities from 2006-2010.
Do participants take part individually or are families/partners involved? Individually
Dementia cases ascertained as part of study: No
Diagnosis based on review of existing clinical data No
Was diagnosis/primary outcomes made blind to exposure variables? Unknown
How many times followed up? 23
Study start date 1946-03-01
Is study ongoing? Yes
Is study still recruiting? No
Inclusion criteria Born in a specified week in March 1946.
Exclusion criteria Excluded births to unmarried mothers and excluded multiple births.

Demographic and Clinical Information

Variable Response
Demographics
Age Yes
Age at time of diagnosis of dementia No
Age at last follow-up Yes
Age at time of death Yes
Sex Yes
Ethnicity Yes
Education Yes
Physical examinations
Any physical examination performed? Yes
Blood pressure Data available
Assessed before onset of dementia
Weight Data available
Assessed before onset of dementia
Height Data available
Assessed before onset of dementia
Neurological examination Data available
Assessed before onset of dementia
Comments: Imaging substudy taking place, see Imaging section of profile.
Extrapyramidal symptoms Data available
Comments: In the Neuroscience substudy.
Heart Rate Data available
Assessed before onset of dementia
Comments: Heart rate response to incremental step test (substudy). See also CV exam.
Anthropometry Data available
Assessed before onset of dementia
Comments: DXA scan and pOCT.
ECG Data available
Assessed before onset of dementia
Cardiovascular examination Data available
Assessed before onset of dementia
Comments: Vascular structure and function: carotid intima-medial thickness (IMT) and arterial distensibility (GE Vivid-I), carotid/femoral pulse wave velocity (Vicorder) and central blood pressure and pulse wave analysis (Sphygmocor) Cardiac structure and function: echocardiography (GE Vivid-I). Images from parasternal long axis and short axis views, apical 5-chamber, 4-chamber, 3-chamber, 2-chamber and aortic views (plus conventional and tissue Doppler in 4-chamber view). Brachial blood pressure (Omron HEM-705), 12 lead ECG (Burdick Eclipse 850i), including 6 min heart rate and respiration recordings by ECG for heart rate variability measurements.
Specific assessment of peripheral vascular disease Data available
Assessed before onset of dementia
Respiratory examination Data available
Assessed before onset of dementia
PEFR Data available
Assessed before onset of dementia
Spirometry Data available
Assessed before onset of dementia
Gait assessment Data available
Assessed before onset of dementia
Comments: In Neuroscience substudy. Walking speed in whole sample.
Opthalmic examination Data available
Assessed before onset of dementia
Acuity Data available: In childhood.
Colour vision Data available
Comments: In Neuroscience substudy.
Specify any others In a substudy:
DXA (Hologic QDR 4500 Discovery): hip (total, femoral neck, trochanter, Ward’s), lumbar spine (L1-4), whole body and region BMD, fat and lean mass, vertebral fracture assessment, aortic calcification score.
pQCT (Stratec XCT 2000) radius: 4% site (trabecular, cortical and subcortical BMD), 50% site (endosteal/periosteal circumference, cortical CS area and thickness, BMC and BMD, CS muscle and fat area, stress strain index, moment of inertia).
Grip strength.
Chair rises, get up and go test.
Chest, upper arm, waist and hip circumference.
Rose angina Scale.
Intermittent claudication, bronchitis, osteoarthritis symptoms, back pain, knee injuries.
Fracture history.
Medical conditions
Cardiovascular disease data Yes
Subgroup: Vascular structure and function: carotid intima-medial thickness (IMT) and arterial distensibility (GE Vivid-I), carotid/femoral pulse wave velocity (Vicorder) and central blood pressure and pulse wave analysis (Sphygmocor) Cardiac structure and function: echocardiography (GE Vivid-I). Images from parasternal long axis and short axis views, apical 5-chamber, 4-chamber, 3-chamber, 2-chamber and aortic views (plus conventional and tissue Doppler in 4-chamber view). Brachial blood pressure (Omron HEM-705), 12 lead ECG (Burdick Eclipse 850i), including 6 min heart rate and respiration recordings by ECG for heart rate variability measurements.
Echography Data available
Myocardial infarction Data available
Medication use for CVD Data available
Hypertension Data available
Systolic/diastolic BP Data available
Mean arterial pressure Data available
Hypotension Data available
Hypercholesterolemia Yes
Virus testing No data available
Olfactory sensitivity No
Medication use No
Drug coding system: Code in accordance with BNF.
Cancer Data available
Diabetic Status Data available

Cognitive Outcomes

Variable Response
Any domain-specific cognitive test performed? Yes
Visual Memory Data available
Data available
N (estimate) : 2,800
Comments: Refer to NSHD website.
List all tests: Visual memory. A 5-item delayed (20 minutes) picture recall task. A summary score is available but this has a strong ceiling effect.
Pen and paper
Computerised: computerised location memory (binding) task in Neuroscience sub-study
Judgement Data available
Data available: See Language and Other IQ Matrix Reasoning in Neuroscience sub-study.
Verbal Memory Data available
Data available
N (estimate): 2, 800
List all tests: Verbal learning: For each of three trials survey members were shown a list of 15 words at a rate of two seconds each, then were asked to write down as many words recalled as possible. A simple total score is available calculated as the sum of the words correctly recalled at each trial. Delayed verbal memory: Survey members were asked to recall, without prior prompting, the name and address they wrote on the envelope used in the previous test (“John Brown, 42 West Street, Bedford”). A maximum score of 6 was achievable for remembering all of these elements.
Pen and paper: Logical memory in Neuroscience sub-study
Visuospatial Function Data available
Data available: See Visual Memory and Other cognitive tasks
Attention Data available
Data available
N (estimate): 2, 800
List all tests: Timed letter search. This is a cancellation task using two different target letters, embedded among non-target letters, with 1 minute per three trials allowed, and outcome measures derived as speed, i.e. position reached at the end of each 1 minute interval, and accuracy, i.e. the number of target letters missed divided by speed. Summary scores are available for the mean speed for each of the three trails and an accuracy score (calculated by dividing the number of missed targets for each trial by the corresponding speed score).
Pen and paper
Reaction time Data available
Data available
List all tests: Reaction time: digit vigilance. Timed letter search: This is a cancellation task using two different target letters, embedded among non-target letters, with 1 minute per three trials allowed, and outcome measures derived as speed, i.e. position reached at the end of each 1 minute interval, and accuracy, i.e. the number of target letters missed divided by speed. Summary scores are available for the mean speed for each of the three trails and an accuracy score (calculated by dividing the number of missed targets for each trial by the corresponding speed score).
Computerised
Language Data available
Data available
N (estimate): Watts-Vernon whole sample.
List all tests: The Watts-Vernon Reading Test, first given at age 15 years, was re-administered at age 26 years, with an additional 10 items of increased difficulty to avoid a ceiling effect (Rodgers, 1986). Verbal fluency: Category fluency was assessed by asking survey members to name as many different animals as possible in 1 minute. The score is the total number of animals named, allowing anything belonging to the animal kingdom (from amoeba to humans), but not counting repetitions, redundancies (e.g. brown cow, spotted cow…) or proper names (e.g. ‘Rover’, ‘Kitty’).
Pen and paper
Vigilance Data available
Data available
N (estimate): 2, 800
List all tests: Reaction time: digit vigilance. Timed letter search. This is a cancellation task using two different target letters, embedded among non-target letters, with 1 minute per three trials allowed, and outcome measures derived as speed, i.e. position reached at the end of each 1 minute interval, and accuracy, i.e. the number of target letters missed divided by speed. Summary scores are available for the mean speed for each of the three trails and an accuracy score (calculated by dividing the number of missed targets for each trial by the corresponding speed score).
Pen and paper
Concentration Data available
Data available: See Vigilance and Attention.
Latent memory Data available
Data available
Pen and paper: Delayed verbal memory: Survey members were asked to recall, without prior prompting, the name and address they wrote on the envelope used in the previous test (“John Brown, 42 West Street, Bedford”). A maximum score of 6 was achievable for remembering all of these elements.
Other cognitive tasks Motor speed and praxis. This task assessed time to move 10 pegs from one hole to an adjacent one. Five trials were administered for each hand. Mean speed scores are available for each hand. For distributional reasons a log transformation of the mean score is recommended.
Prospective memory (sometimes referred to as ‘remembering to remember’). Survey members were informed that, at a later stage of the interview, they would be given an envelope and asked to write a name and address on it, and that, on receipt of the envelope, they were to remember to turn it over, seal it, and write their initials on it. For the outcome variable a full score of 3 was achieved if both actions were completed without prompting, 2 if one action was achieved without prompting, and 0 if no action was undertaken without a prompt. : Computerised vasomotor integration (tracing) and set-shifting (Flanker-type) tasks in Neuroscience sub-study.
Finger tapping: tap as many times as possible at 15 using a device.
IQ data available? Yes
NART Yes
IQ other (list) NSHD-specific general non-verbal and verbal intelligence testing. In 1961, at the age of 15, study members were given their third set of cognitive tests. The tests were selected to look at a broad range of abilities and included verbal and non-verbal reasoning, reading and mathematics, and followed on from similar tests given at ages 8 and 11. These tests were given to study members under the supervision of a member of their school staff.
The tests selected in 1961 were the Alice Heim (AH4) test, the Watts-Vernon reading test and a mathematics test specifically constructed for the NSHD. In the full set administered there were 212 questions grouped into four separate timed tests. The tests themselves were ideally given to study members in the morning, on two consecutive days. On the first day study members sat the verbal and non-verbal reasoning tests. On the second day the reading and mathematics tests were given.
General ability- non verbal.
General ability- verbal.
Reading test and mathematics tests specifically developed for the study.
Examples of tests are shown here: http://www.nshd.mrc.ac.uk/nshd/cognitive-tests/.
Cognitive background? Yes
Years of education Yes
Level of education Yes
Parental education Yes
Standard dementia global cognition scales? Yes
MMSE Subgroup
Comments: This is being collected in the N=500 Neuroscience substudy.
MoCA No
ADAS-Cog No
Addenbrooke's Cognitive Exam Yes
Comments: iPad based ACE-III at 69 year home visit. Developed by University of Plymouth.
3MS No
GPCOG No

Non-Cognitive Clinical Outcomes

Variable Response
Dementia diagnosis
Alzheimer's dementia No
Lewy Body Disease No
Huntingtons Disease No
Parkinsons Disease No
Frontotemporal dementia No
Vascular dementia No
MCI No
Subjective complaint Yes
Dementia diagnosis (Other comments) Yes
Functional rating scales
Any information on dementia rating collected? Yes
ADCS-ADL No
ADCS-ADL-MCI No
Blessed Dementia Scale No
Clinical dementia rating scale (CDR) No
Complex Activities of Daily Living Yes
Dependence Scale No
Functional Assessment Questionniare (FAQ) No
FAST No
Global Deterioration Scale (GDS) No
Katz ADL No
Lawton IADL No
PDQ39 (PD specific) No
UPDRS (PD specific) Yes
Subgroup
Comments: In the amyloid neuroimaging substudy, see Imaging.
Hoehn and Yahr (PD specific) Yes
Subgroup
Comments: In the Neuroscience substudy as part of UPDRS, see Imaging.
Schwab and England (PD specific) Yes
Subgroup
Comments: In the neuroscience substudy as part of UPDRS, see Imaging.
UHDRS (HD specific) No
Any information on subjective complaints collected? No
Any neuropsychiatric rating scale administered? Yes
Aggression Scale No
Beck Depression Inventory No
Behave-AD No
Center for Epidemiologic Studies Depression scale (CES-D) No
Connor-Davidson Resilience Scale No
Cornell depression Scale No
Geriatric Depression Scale (GDS) No
Hamilton depression rating scale (HDRS) No
Montgomery-Asberg depression scale (MADRS) No
NPI No
NPI-Q No
Speilberger State Anxiety Scale No
Specify any other scales No
Any Quality of Life Data Colllected? Yes
Quality of Life-Alzheimers Disease (QOL-AD) No
Dementia Quality of Life Instrument (DEMQOL) No
Discomfort Scale for Dementia of Alzheimers Type (DS-DAT) No
Progressive Deterioration Scale (PDS) No
Quality of Life in Late-Stage Dementia Scale (QUALID) No
Bedfords Alzheimers Nursing Severity Scale(BANS-S) No
EQ-5DVAS No
Short Form (SF) 36 Yes
Health Utilities Index 1, 2 or 3 No
Specify any other quality of life scales General Health Questionnaire done several times (GHQ) 28. GHQ28, The Close Person Questionnaire, life events, Edinburgh wellbeing scale, life satisfaction, neighbourhood satisfaction, spare time activities, time spent caring for others.
ADL and iADL scales, non-dementia specific.
Any information on Caregivers and Caregiving Collected? Yes
Caregivers for Alzheimers disease Problems Scale (CAPS) No
Community Dementia Quality of Life Profile (CDQLP) No
COQoL-AD No
Dementia Management Strategies Scale (DMSS) No
Caregiver Activity Survey (CAS) No
Quality of life of caregivers (CQOL) No
Screen for Caregiver Burden/Time Spent Caregiving (TSC) No
Work Productivity and Activity Impairment Questionnaire-dyad version (WPAI-DYAD) No
Zairit Burden No
Health service utilisation
Any Health Resource Utilisation Collected ? Yes
Hospital utilisation Yes
Prescription Medicine Cost No
Over the Counter Drug Costs No
Nursing Home Costs No
Costs of Visits to Specialists (out-patient) No
Costs of Home-Care No
Admission to nursing home Yes
Admission to home care No
Day care at nursing home No
Day care at home for elderly No
Home care- domestic Yes
Home care- personal care No
Home care- nursing No
Physical therapist No
Care of community mental health team No
Permanent stay at nursing home No
Informal ADL care Yes
Informal iADL care Yes
Days of work absence if having a paid job No
Other neurological or psychiatric measurements? Yes
Any stroke data? Yes
Stroke type Yes
Transient Ischemic Attack Yes
Carotid plaques Yes
Any head trauma data? Yes
Loss of consciousness Yes
Sports, soccer and boxing No
Head trauma severity Yes
BISQ or equivalent No
EEG No
Psychiatric evaluations Yes
CESD scale (depression) No
Personality evaluation Yes
Personality evaluation comments Comments: Teacher rated behaviour in adolescence, MPI at 16 years.
Apathy evaluation No
Anxiety measure No
Resilience evaluation No

Imaging

Variable Response
For imaging data, what format(s) do you use for storing data? Methods paper is being planned, therefore SOPs will not be available.
Structural T1 Acquired
Acquired: Neuroscience substudy begun 2015. Participants will be seen twice.
N controls: 500: sample is randomly recruited from general population
Acquisition period: 2015-2019.
Field strength: 3T
Fluid attenuation inversion recovery (FLAIR) Acquired
Acquired
Diffusion imaging (DTI/DWI) Acquired
Acquired
f-MRI (task) Not acquired
Not acquired
f-MRI (rest) Not acquired
Not acquired
PET Acquired
Acquired: Florbetapir. Substudy begun 2015.
N controls: 500
Acquisition period: 2015-2019. Seen twice.
Scanner N: Single
Field strength: 3T
SPECT Not acquired
Not acquired
MEG Not acquired
Not acquired
In vivo Spectroscopy Not acquired
Not acquired
Other (please specify) Carotid artery scanning ultrasound.
Cardio echo 2D.
Do you use an imaging data management system (e.g. XNAT or LORIS)? Yes
If yes, which system do you use? XNAT
Primary contact for the technical aspects of the imaging data David Cash. Methods paper is being planned, therefore SOPs will not be available.

Genetics

Variable Response
Overview
Number Gwas subjects Controls N
Controls N: 2, 500 planned
Controls % male: 50%
Consortia: UCLEB
Comments: Planned using a custom Illumina chip.
Gwas platform Illumina
Human Cardio-Metabochip: Human Cardio-Metabochip: N= 2,500 as part of UCLEB. Human Drug target array: N=2,500 as part of UCLEB
N imputed subjects Cases % male
Cases % male: 50%
Controls N: 2, 500
Consortia: UCLEB
Imputation reference panel 1000 Genomes unspecified
Exome/Genome sequencing broad platform categories Illumina
N Whole genome sequenced No
Genome sequencing broad platform categories Illumina
N APOE genotyped Controls N
Controls N
Consortia: NA
Gene screening
APOE Yes
Estimated N: 2, 500
TREM2 No
APP No
PSEN1 No
PSEN2 No
GRN No
MAPT No
C9ORF72 No
VCP No
CHMP2B No
TDP-43 No
PRNP No
SNCA No
LRRK2 No
PINK1 No
PARK2 No
PARK7 No
NOTCH3 No
CST3 No
TTR No
GSN No
ITM2B No
HTT No
NPC1 No
NPC2 No

Biological samples

Variable Response
Blood collected Yes
Plasma Yes
Serum Yes
RNA Yes
DNA Yes
Abeta 1-40 No
Abeta 1-42 No
Abeta x-40 No
Abeta x-42 No
Blood Metabolic Analytes
CRP (c-reactive protein) Yes
eGFR (estimated Glomular Filtration Rate) Yes
Glucose Yes
HbA1c Yes
Lipids Yes
Liver Function Tests Yes
Serum creatinine Yes
Homocysteine Yes
Folate Yes
Other blood samples Yes
Are laboratory protocols and storage information available for bloods Yes
Urine collection
Urine Yes
Subgroup
Details: Dipstick, spun and unspun aliquots stored at –80 and –20°C.
Autopsy data
Autopsy No
Measurements already performed No
Saliva
Saliva collected Yes
Subgroup
Repeated Collection
Details: One salivary sample was collected at the visit and a further three during the following 24 h (evening, next day waking and 30 min later).
Cortisol Yes
Are laboratory protocols and saliva storage information available? Yes
CSF
CSF collected No
Are CSF laboratory protocols and storage information available? No
mtDNA abnormalities No
Oxidative stress No

Brain donation

Variable Response
Is brain donation part of the existing protocol? Yes
Are information sheets made available to representative or consultees? Yes
Are retrospective interviews carried out after the participant's death? No
Is there a procedure for declining donation/failed recruitment/project termination? No
Has an actuarial analysis been completed? Yes

Lifestyle

Variable Response
Smoking Yes
Pack years Data available
Current smoking Data available
Former smoking Data available
Alcohol Data available
Comments: Dietary and alcohol assessment (5-day diary).
Units per day/week vs weekend Data available
Comments
Specified beverage type (wine, spirits, beers) Data available
Abstainers/former users Data available
Alcohol Use Disorders Identification Test (AUDIT) or other screen instrument (name) Data available: AUDIT and CAGE
Binge drinking Data available
Drugs of abuse assessment
Obesity and associated risk factors
BMI Data available
Hip/waist circumference Data available
Fat percentage Data available
Dyslipidemia Data available
Blood lipids Data available
Metabolic syndrome Data available
Type of exercise: heavy, light Data available
Exercise duration Data available
Objective measures of activity Data available
Comments: Actiheart for 5 days in 2006-2010. 7 days for new wave.
Objective measure of fitness (VO2) Data available
Comments: Incremental step test.
Other measurements of activity Physical activity assessment (EPAQ2).
Diet Yes
Carbs, protein, fats, fish oil Data available
Comments: Dietary and alcohol assessment (5-day diary)
Anti-oxidants Data available
Comments: Dietary and alcohol assessment (5-day diary)
Vegetarian? Data available
Comments: Dietary and alcohol assessment (5-day diary)
Shortage of food Data available
Comments: Dietary and alcohol assessment (5-day diary)
Coffee and caffeine Data available
Comments: Dietary and alcohol assessment (5-day diary)
Vitamin A, B, E Data available
Comments: Dietary and alcohol assessment (5-day diary)
Fat intake MUFA, PUFA Data available
Comments: Dietary and alcohol assessment (5-day diary)
Food questionnaires Data available
Other dietary items Yes
Employment status
Employment status Data available
Living situation
Living situation Data available
Socioeconomic status
Socioeconomic status measures Data available
Sleep assessment
Questionnaires Data available
Comments: Number of hours asleep plus self report sleep quality rating.
Actigraphy to measure sleep patterns Data available

Ethics and Engagement

Variable Response
Participant engagement
Is there participant representation in the governance of the cohort? No
Do existing mechanisms for consulting/involving participants exist? Focus group for the Neuroscience substudy and will utilise those in future.
If so, does this happen on an ongoing or an ad hoc basis? Ad hoc basis based on new developments in the study.
Ethics
Is there an ethics advisory or ELSI group within the cohort governance? Steering group committee and risk management sub-committee.
Does the cohort include participants who lack capacity? Yes
Is there a process in place for participants who lose capacity? Yes
Do participants provide contact information for a person to act as a potential consultee? Yes
Disclosure
Do procedures exist for the disclosure of incidental findings? Yes
What kinds of finding do these relate to? (imaging, genotyping, etc) Clinically relevant imaging, biological samples. Not genetics, not cognitive, with the exception of the MMSE used in the substudy.
Who is responsible for disclosing incidental findings? Neuroradiologist assesses clinical relevance of the imaging findings and report this to the GP as well as the study member. Study member advised to see GP and offered a referral.
Do procedures exist for the disclosure of clinically relevant information identified as a direct focus of the study? (e.g. a diagnosis of dementia) No
Recruitment
How was the cohort recruited (NHS or not, primary or secondary care)? Birth registrations in one week in March 1946.
Does the study involve ongoing connections with participants' own doctors (e.g. GPs)? Yes
Consent and recontact
Is there consent for recontact? Yes
If so, under what conditions? The participants re-consent every time they take part in another wave of the study. 'Consent for future studies' Form: "In the future when we wish to contact you again, if we found that we were unable to contact you personally, for example if you had a long-term illness or were unable to speak to us, would you be prepared for us to collect information about your circumstances from <your husband/wife/partner> or from a close friend?"

Data Management

Variable Response
Consent for linkage to routine data
Which parts of the UK are represented by participants in your cohort? England
England
Scotland
Wales