National Child Development Study: Age 42, Sweep 6, 1999-2000

<p>The <span style="font-style: italic;">National Child Development Study</span> (NCDS) is a continuing longitudinal study that seeks to follow the lives of all those living in Great Britain who were born in one particular week in 1958. The aim of the study is to improve understanding of the factors affecting human development over the whole lifespan. <br><br>The NCDS has its origins in the <span style="font-style: italic;">Perinatal Mortality Survey</span> (PMS) (the original PMS study is held at the UK Data Archive under SN 2137). This study was sponsored by the National Birthday Trust Fund and designed to examine the social and obstetric factors associated with stillbirth and death in early infancy among the 17,000 children born in England, Scotland and Wales in that one week. Selected data from the PMS form NCDS sweep 0, held alongside NCDS sweeps 1-3, under SN 5565. <br><span style="font-style: italic;"><br>Survey and Biomeasures Data (GN 33004):</span><br>To date there have been ten attempts to trace all members of the birth cohort in order to monitor their physical, educational and social development. The first three sweeps were carried out by the National Children's Bureau, in 1965, when respondents were aged 7, in 1969, aged 11, and in 1974, aged 16 (these sweeps form NCDS1-3, held together with NCDS0 under SN 5565). The fourth sweep, also carried out by the National Children's Bureau, was conducted in 1981, when respondents were aged 23 (held under SN 5566). In 1985 the NCDS moved to the Social Statistics Research Unit (SSRU) - now known as the Centre for Longitudinal Studies (CLS). The fifth sweep was carried out in 1991, when respondents were aged 33 (held under SN 5567). For the sixth sweep, conducted in 1999-2000, when respondents were aged 42 (NCDS6, held under SN 5578), fieldwork was combined with the 1999-2000 wave of the <span style="font-style: italic;">1970 Birth Cohort Study</span> (BCS70), which was also conducted by CLS (and held under GN 33229). The seventh sweep was conducted in 2004-2005 when the respondents were aged 46 (held under SN 5579), the eighth sweep was conducted in 2008-2009 when respondents were aged 50 (held under SN 6137), the ninth sweep was conducted in 2013 when respondents were aged 55 (held under SN 7669), and the tenth sweep was conducted in 2020-24 when the respondents were aged 60-64 (held under SN 9412). <br><br>A <span style="font-style: italic;">Secure Access</span> version of the NCDS is available under SN 9413, containing detailed sensitive variables not available under Safeguarded access (currently only sweep 10 data). Variables include uncommon health conditions (including age at diagnosis), full employment codes and income/finance details, and specific life circumstances (e.g. pregnancy details, year/age of emigration from GB).<br><br>Four separate datasets covering responses to NCDS over all sweeps are available. <span style="font-style: italic;">National Child Development Deaths Dataset: Special Licence Access</span> (SN 7717) covers deaths; <span style="font-style: italic;">National Child Development Study Response and Outcomes Dataset</span> (SN 5560) covers all other responses and outcomes; <span style="font-style: italic;">National Child Development Study: Partnership Histories</span> (SN 6940) includes data on live-in relationships; and <span style="font-style: italic;">National Child Development Study: Activity Histories</span> (SN 6942) covers work and non-work activities. Users are advised to order these studies alongside the other waves of NCDS.<br><br>From 2002-2004, a Biomedical Survey was completed and is available under Safeguarded Licence (SN 8731) and Special Licence (SL) (SN 5594). Proteomics analyses of blood samples are available under SL SN 9254.<br><br><span style="font-style: italic;">Linked Geographical Data (GN 33497): <br></span>A number of geographical variables are available, under more restrictive access conditions, which can be linked to the NCDS EUL and SL access studies. <br><br><span style="font-style: italic;">Linked Administrative Data (GN 33396):<br></span>A number of linked administrative datasets are available, under more restrictive access conditions, which can be linked to the NCDS EUL and SL access studies. These include a <span style="font-style: italic;">Deaths</span> dataset (SN 7717) available under SL and the <span style="font-style: italic;">Linked Health Administrative Datasets</span> (SN 8697) available under Secure Access.<br><br><span style="font-style: italic;">Multi-omics Data and Risk Scores Data (GN 33592)<br></span>Proteomics analyses were run on the blood samples collected from NCDS participants in 2002-2004 and are available under SL SN 9254.  Metabolomics analyses were conducted on respondents of sweep 10 and are available under SL SN 9411. Polygenic indices are available under SL SN 9439. Derived summary scores have been created that combine the estimated effects of many different genes on a specific trait or characteristic, such as a person's risk of Alzheimer's disease, asthma, substance abuse, or mental health disorders, for example. These scores can be combined with existing survey data to offer a more nuanced understanding of how cohort members' outcomes may be shaped.<br><br><span style="font-style: italic;">Additional Sub-Studies (GN 33562):<br></span>In addition to the main NCDS sweeps, further studies have also been conducted on a range of subjects such as parent migration, unemployment, behavioural studies and respondent essays. The full list of NCDS studies available from the UK Data Service can be found on the <a href="https://beta.ukdataservice.ac.uk/datacatalogue/series/series?id=2000032#!/access-data" target="_blank" style="background-color: rgb(255, 255, 255);">NCDS</a> series access data webpage.<br><br><span style="font-style: italic;">How to access genetic and/or bio-medical sample data from a range of longitudinal surveys:<br></span>For information on how to access biomedical data from NCDS that are not held at the UKDS, see the <a href="https://cls.ucl.ac.uk/data-access-training/genetic-data-and-biological-samples/" target="_blank" style="background-color: rgb(255, 255, 255);">CLS Genetic data and biological samples</a> webpage.<br><br>Further information about the full NCDS series can be found on the <a href="https://cls.ucl.ac.uk/cls-studies/1958-national-child-development-study/" target="_blank" style="background-color: rgb(255, 255, 255);">Centre for Longitudinal Studies</a> website.<br><br></p>
<p><i>NCDS6:</i><br>
The sixth NCDS sweep took place in 1999-2000, when cohort members were aged 41-42 years. Fieldwork was combined with the 29-year follow-up for the
<i>1970 British Cohort Study</i> (BCS70), also conducted by CLS.<br>
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SN 5578 supersedes the former combined NCDS6/BCS70 1999-2000 dataset, which was held under SN 4396
<i>National Child Development Study and 1970 British Cohort Study (BCS70) Follow-ups, 1999-2000</i>. The Centre for Longitudinal Studies updated the first six waves of NCDS in late 2006, and as part of this work separated the composite NCDS6/BCS70 dataset. Improvements made include further data cleaning and the addition of new documentation. Users who have previously obtained SN 4396 should no longer use it, and should completely replace it with this one. The BCS70 component of SN 4396 is now held separately under SN 5558 <i>1970 British Cohort Study: Twenty-Nine-Year Follow-up, 1999-2000</i>.</p><p><span style="font-style: italic;">Latest edition information</span><br>For the third edition (November 2024), 14 new variables have been added. These variables correspond to truncated ICD-10 codes, limited to the first letter, derived from free-text responses regarding general health issues, kidney and bladder conditions, and long-standing illnesses. In addition, a small number of variables have been removed as a result of a disclosure review.</p>