Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS

City, University of London requires continuing access to previously provided data. These data were provided for the purpose of maintaining a research database which can potentially be accessed by authorised researchers using the secure environment of the Office for National Statistics, ONS Secure Research Service (SRS) formerly known as the Virtual Microdata Laboratory (VML).

No new data are requested in this agreement. It includes the same analyses as the previous Data Sharing Agreement.

All the data provided to the project had already been collected through the processes of civil registration, birth notification, compiling the Hospital Episode Statistics or perinatal audit by the now disbanded Centre for Maternal and Child Enquiries. There was no primary data collection.

The database was created as a result of three collaborative projects led by City, University of London over a period of more than ten years the first of these funded by City University Research Assessment Exercise Development Fund involved pilot linkage of birth registration records to birth notification records, previously known as the NHS Numbers for Babies (NN4B) records. Birth registration records were already linked by the Office for National Statistics (ONS) to death registration records for babies who died. The pilot was successful and ONS mainstreamed the linkage for the years 2006 onwards. Since then, the linked records have been used for publications and research and the data have been provided already being for further linkage to other.

In the second project, funded by the Medical Research Council (MRC), the already linked birth registration and notification data were further linked to HES Maternity delivery and birth records and permission was given to hold these as a database. This database adds value to the HES data by adding further data items from birth registration and notification and more complete data for important data items, notably birthweight and gestational age where HES are incomplete. It was created to enable ‘analyses relating to inequalities in the outcome of pregnancy and information for service users about the outcome of midwifery, obstetric and neonatal and related health care’.

As part of the third project, -‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS, funded by NIHR, there was further linkage of birth and delivery records to admitted patient care records relating to any subsequent admissions of these mothers and children to hospital and a relational database was constructed to hold the linked records.

Funding was secured from ESRC for a follow on project, ‘Implications of time of day and day of week for the outcome of birth’ which used the same data to do some of the uncompleted analyses from the third project.

The lawful basis for processing personal data under the UK GDPR is:

Article 6(1)(e) - processing is necessary for the performance of a task carried out in the public interest or in the exercise of official authority vested in the controller

The lawful basis for processing special category data under the UK GDPR is:

Article 9(2)(j) - processing is necessary for archiving purposes in the public interest, scientific or historical research purposes or statistical purposes in accordance with Article 89(1) based on Union or Member State law which shall be proportionate to the aim pursued, respect the essence of the right to data protection and provide for suitable and specific measures to safeguard the fundamental rights and the interests of the data subject.

The processing is in the public interest as there is a substantial public health interest and scientific purposes as evidenced by consultations held with service users as part of the research and in the extent of media coverage when the analyses have been published.

City, University of London is the Controller and responsible for managing access to the database and the purpose(s) for which the data may be used.

ONS is a processor acting under the instructions of City, University of London. ONS role is limited to the storage of the database in the ONS SRS.

City, University of London may only grant access to the research database which City University of London produced, to researchers who have the necessary ethics and Section 251 approvals for purposes approved by NHS England.

All individuals accessing the data work under the supervision of City, University of London under conditions defined by ONS when carrying out the work, using ONS’ secure facilities that are required when handling identifiable data.

No record-level data may be accessed outside of the secure environment of the SRS.

This Data Sharing Agreement covers only the data supplied by NHS England; not the ONS data to which it is linked.

The aims of the project were to compare daily, weekly and yearly variations in numbers of spontaneous and other births by time, day and season of birth and to compare variations in rates of adverse outcome. The project aimed to answer the following questions:

1. How do numbers of births vary according to time of day, day of the week and time of year of birth and how does this relate to methods of onset of labour and delivery and multiplicity?

2. Subject to the availability of data, how do patterns of birth vary between maternity services in relation to variations in medical and midwifery staffing, patterns of intervention and size of unit?

3. How does the outcome of pregnancy in terms of rates of cause specific intra-partum stillbirth and neonatal and infant mortality rates and rates of morbidity recorded at birth and at hospital admission in the first year of life vary according to time of day, day of the week and time of year in relation to gestational age, and intervention in the onset of labour and delivery?

4. Have the patterns observed changed over the years 2005 onwards?

The project analysed separately births before term and those after full term pregnancies. In addition, it took account of whether labour and delivery occurred spontaneously or whether their timing was affected by inducing labour, or by undertaking either a planned caesarean section or an emergency caesarean section during labour.

The University of Oxford was doing preparatory work before applying for an extract of the pseudonymised linked dataset for the purpose of a separate project called ‘Tracking the Impact of Gestational Age on Health, Educational and Economic outcomes: a Longitudinal Record Linkage Study (TIGAR)’. This has now been agreed by NHS England under a separate Data Sharing Agreement, reference DARS-NIC-09637-Y8T1N.

In advance of that application for approval, the TIGAR study's Principal Investigator and a co-investigator, both of whom are employed by the University of Oxford at the National Perinatal Epidemiology Unit (NPEU), had been supporting the personnel from City, University of London by undertaking quality assurance and data cleaning exercises to assure and improve the quality and completeness of matching the birth records with the HES records including subsequent admissions. Under a previous Data Sharing Agreement (DARS-NIC-10094-P6P4B-v6.7), the principal investigator and co-investigator of the TIGAR project were the only personnel from the University of Oxford who were permitted to access the data and access was for the purpose of quality assurance and data cleaning.

To clarify, researchers on the TIGAR project led by the University of Oxford are no longer involved in this project. The work they did to quality control the data they went on to use has finished and the relevant data, a subset of the whole cohort were transferred to their project area, where they were analysed under their Data Sharing Agreement. This project has now finished and ONS is currently deleting these data.

The output of the data linkage and subsequent quality assurance was the creation of the research database which is stored within ONS, accessed only via the SRS subject to the controls outlined above. The database was created as an output of the previous project. Some of the quality assurance was undertaken as part of the NIHR-funded project and further quality assurance was undertaken by the two TIGAR researchers from the University of Oxford. There is still further quality assurance work to be done however this will be done solely by City, University of London.

From the NIHR-funded project, ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’, the outputs listed below have been delivered or are expected.

City, University of London submitted four articles to peer reviewed journals and a final report to the National Institute for Health Research (NIHR). Two articles have been published by BMJ Open, a weekly peer reviewed medical journal and a further article was published in PLOS1, a peer reviewed open access scientific journal. The fourth was rejected and needs revision before resubmission. NIHR has published the final report in its online journal. City, University of London and its collaborators have also given oral and poster presentations at a number of conferences, as shown on the list below. Further articles will be written, based on work already partly completed and the further analyses which were subsequently funded.

City, University of London will write and submit a further article summarising findings to Significance, the Royal Statistical Society’s magazine which aims to popularise statistics. It was intended that this article plus the revised article mentioned above would have been submitted for publication 2021 but these were delayed by the coronavirus pandemic. On the other hand, at a time early in the pandemic, City, University of London took the opportunity to write an article on public engagement work for a special issue of the International Journal of Population Data Linkage.

The study team planned to submit at least three articles to peer reviewed journals based on the SDAI funded work, one on the outcome of births by time of day and day of the week, one on differences between maternity units and one on the linkage and analysis of data about births in Wales. The article on neonatal mortality by time of day and day of the week is at advanced draft stage and nearly ready for submission for publication. The work in it has formed the basis of two abstracts which have been accepted for presentation at conferences in September 2022. The work on differences between maternity units is still at an early stage and more work is needed. Although descriptive analyses of the data for Wales have been undertaken, statistical modelling is needed to complete the work. It is not possible to set targets at present as work was severely delayed by data access problems at the beginning of the pandemic and further funding will be needed to finish the work in addition to a renewal of this Data Sharing Agreement.

When each of these articles are accepted, the study team will continue to work with City’s press office to maximise coverage. The article on the timing of birth published in 2018 was well reported in the national media and there were over 370 press reports.

Opportunities will be taken to continue to present findings at professional conferences and the team aims to contribute to publications, such as the research summaries included on the Royal College of Midwives magazine, ‘Midwives’.

Public and Patient Involvement is at the heart of this project and reaches well beyond the minimum required by funders. It was originally intended that results in the form of aggregated statistics, which may have included some sub-national results with small numbers suppressed, would be provided to the National Childbirth Trust (NCT) for its work in providing services and materials to prospective and actual parents. NCT subsequently dropped out of the project and City, University of London are now engaging with National Maternity Voices instead, using different approaches (but still within the boundaries and purpose of the existing protocol and previous Data Sharing Agreement).

In October 2021, City, University of London's public engagement work was awarded an ONS Data Capability Award.

A member of the project team, with extensive experience of research engagement, disseminated the findings to parent representatives and ‘patient’ advocates serving on maternity services liaison committees and labour ward forums with the aim of highlighting research findings and service users’ views and priorities to clinical managers and commissioners. In the follow on project, the person concerned, who previously was employed by NCT, has been employed by City, University of London.

NCT also involves its members in representing the views of service users to the maternity services and also participating in research projects to represent users’ views. Three meetings of NCT members and others who are service user representatives on Maternity Services Liaison Committees and Maternity Voices Partnerships to do this were held in relation to the third project. They were useful in exploring service users’ concerns about possible temporal variations in the safety of birth, including positive and negative implications of birth at night and at weekends. Two more were planned as part of the ESRC-funded follow-on project, but because of the coronavirus pandemic, they were replaced with online engagement activities which had the same aim. An article will be submitted for publication to describe the innovative approaches developed for this work. No one involved in this aspect of the project has access to individual service users’ records.

The following outputs have been produced to date:

Outputs from NIHR funded work

Articles in peer reviewed journals:

Dattani N, Macfarlane A. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005-2014: methods. A population-based birth cohort study. BMJ Open 2018;8:e017897. doi:10.1136/ bmjopen-2017-017897

Harper G. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005–2014: Quality assurance of linkage of routine data for singleton and multiple births. BMJ Open Mar 2018, 8 (3) e017898; DOI: 10.1136/bmjopen-2017-017898

Martin P, Mario Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N, Macfarlane A. Timing of singleton births by onset of labour and mode of birth in NHS maternity units in England, 2005 – 2014: a study of linked birth registration, birth notification, and hospital episode data. PLoS ONE 2018 Jun 14;13(6): e0198183. https:/doi.org/10.1371/journal.pone.198183. . eCollection 2018.

To be revised and resubmitted:

Dattani N. Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Submitted to Birth. Rejected with suggestions for a revised article which will be redrafted and submitted.

Final report to NIHR:

Macfarlane A, Dattani N, Gibson R, Harper G, Martin P, Scanlon M, Newburn M, Cortina-Borja M. Births and their outcomes by time, day and year: a retrospective birth cohort data linkage study. Health Serv Deliv Res 2019;7(18).

Other articles:

Rapid response to BMJ ‘Association between day of delivery and obstetric outcomes: observational study’ was published as a BMJ Rapid Response 25 November 2015. URL: http://www.bmj.com/content/351/bmj.h5774/rr-7

Macfarlane A. Day and time of birth and mode of onset and birth. Research Summary 3. Practice: Research summary 3. Midwives / Winter 2018; 34. cm.org.uk/midwives

Birth cohort data linkage study. https://www.adruk.org/our-mission/our-impact/article/birth-cohort-data-linkage-study-228/

Birth and its outcome by time, day and year: a birth cohort data linkage study. School of Health Sciences, City, University of London. https://www.ons.gov.uk/file?uri=/aboutus/whatwedo/statistics/requestingstatistics/approvedresearcherscheme/arlistjan2020forpublication.xls

Oral presentations:

Dattani N, Macfarlane A, Datta-Nemdharry P. Using data linkage to create a national database of birth and maternity data. Presentation at Royal Statistical Society Conference, Sheffield, September 2014.

Macfarlane AJ. ‘Care.data’: Bungled opportunity or unjustified intrusion? Invited presentation to Royal Statistical Society meeting. October 7 2014.

Macfarlane A, Dattani N. Using linkage of administrative data to build a national database for analysis of birth and its outcome in England and Wales. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Quality Assuring Linked Birth Registration and Hospital Episode Statistics Delivery Records – results and lessons learned. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Insights on Third Party Linkage and Data Quality from Quality Assuring Linked Birth Registrations and HES Delivery Records in England 2005 to 2014. Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Macfarlane A, Martin P, Cortina-Borja M. Dattani N, Harper G, Newburn M. Gibson R. ‘A time to be born’? Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Martin P, Cortina-Borja M, Dattani N, Harper G, Gibson R, Newburn M, Dodwell M, Macfarlane A. Variations in numbers of births by day of the week in relation to onset of labour and mode of giving birth, England 2005-2014. Oral presentation at Royal Statistical

Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Cortina Borja M, in collaboration with Macfarlane A, Dattani N, Dodwell M, Gibson R, Harper G, Martin P, Newburn M. Modelling numbers of births by day of the week in relation to onset of labour and mode of giving birth in England 2005–2014. Talk to RSS South West local group, Plymouth University, 20th February 2019.

Macfarlane A, Dattani N. Building a birth cohort of births and their outcome in England and Wales using linkage of administrative data. Oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Macfarlane A, Dattani N. Analysis of births England and Wales by time of day and day of the week and place of birth using linked administrative data. Rapid fire presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Conference posters:

Dattani N, Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Macfarlane A, Dattani N. Using data linkage to build a national database of data about birth and its outcome for policy analysis in England and Wales. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Harper G, Macfarlane A, Dattani N, Dodwell M, Newburn M, Gibson R, Cortina-Borja M, Martin P. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Poster presented at the International Population Data Linkage Conference, Swansea, Wales, 24-26 August 2016.

Macfarlane A, Dattani N, Harper G, Cortina-Borja M, Martin P, Gibson R, Dodwell M, Newburn M. Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for midwifery care. Poster presented at the Royal College of Midwives Annual Conference. Harrogate, October 19-20 2016.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. ‘A time to be born?’ Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England. Winner of the Scientific Review Team Prize.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. Births: the weekly cycle. Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England

Oral presentations

Coathup V, Macfarlane A, Quigley M. Evaluating record linkage of birth registration and notification records to Maternity Hospital Episode Statistics and childhood hospital readmissions: Singleton births in 2005 and 2006 across England. Oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Outputs from ESRC SDAI-funded work

Articles in peer-reviewed journals:

Newburn M, Scanlon M, Plachcinski R, Macfarlane A. Involving service users in the Birth Timing Project, a data linkage study analysing the timing of births and their outcomes. International Journal of Population Data Science (2020) 5; 3 :1366. https://doi.org/10.23889/ijpds.v5i3.1366

Carty L, Grollman C, Plachcinski R, Cortina-Borja M, Macfarlane A.

Neonatal mortality in NHS maternity units by timing and mode of birth: a retrospective linked cohort study

BMJ Open 2023;13:e067630. doi: 10.1136/bmjopen-2022-067630.

Work is still under way on the following draft articles

Provisional titles/authors:

Maternal death and timing of birth in the NHS in England, 2008 to 2013; Christopher Grollman, Lucy Carty, Rachel Plachcinski, Mario Cortina Borja, Alison Macfarlane

Ethnic disparities in maternal mortality in England, 2008 to 2013: retrospective cohort study using the City Birth Cohort; Christopher Grollman, Lucy Carty, Rachel Plachcinski, Mario Cortina Borja, Alison Macfarlane

Oral presentations:

Miranda Scanlon, Mary Newburn, [Nirupa Dattani], Rachel Plachcinski, Alison Macfarlane. Public involvement and engagement with an analysis of births in different settings by time of day and day of the week using linked data. Oral presentation at the 15th International Normal Labour and Birth Research Conference, India. December 2020. Winner of the first prize for oral presentation. https://youtu.be/FEU6R1xpNUA

Miranda Scanlon, Mary Newburn. Presentation based on the above to the KCL Maternal Health Systems and Policy Research Group Meeting 15 March 2021.

Scanlon M, Newburn M, Plachcinski R, Macfarlane A. Involving the public with an analysis of daily, weekly, and yearly cycles of births using linked data. Online Presentation in ONS Research Excellence Series. May 17 2022.

Plachcinski R. Invited plenary speaker. International Population Data Linkage Conference, Edinburgh, September 7-9 2022.

Carty L, Cortina-Borja M, Rachel Plachcinski, Grollman C, Macfarlane A. Neonatal mortality in NHS maternity units by timing of birth and method of delivery: a retrospective linked cohort study. Oral presentation. International Population Data Linkage Conference, Edinburgh, September 7-9 2022.

Carty L, Cortina-Borja M, Rachel Plachcinski, Grollman C, Macfarlane A. Is ‘out of hours’ birth dangerous? a retrospective linked cohort study. Rapid fire presentation. Royal Statistical Society International Conference, Aberdeen, September 12-15, 2022.

“Neonatal mortality in NHS maternity units by timing of birth and mode of birth: a retrospective linked cohort study” (Chris Grollman, Lucy Carty, Mario Cortina-Borja, Rachel Plachcinski, Alison Macfarlane) to be presented at the Society for Social Medicine conference in Newcastle, 6-8th September 2023

The establishment of the research database for which City, University of London has Health Research Authority approval, permits additional research into maternity and its outcome. This database provides a more complete resource than any of the datasets individually by combining birth registration, birth notification and HES. This has enhanced HES by linking it to a fuller and more complete dataset and also adding variables which are not in Maternity HES.

The establishment of the database in its current form was funded as part of the NIHR-funded third project ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’. The aim of the parts of the project completed was to provide a better understanding of daily, weekly and seasonal variations in patterns of birth and this has been achieved. City, University of London has also made progress in ascertaining the impact of these differences on variations observed in outcomes, in order to assess the extent to which these reflect selection and to inform improvements in the planning of maternity services.

The analyses done in this project show the extent of daily and weekly variations in numbers of singleton births and these have implications for the planning and staffing of maternity services. This and the other work done has been described in detail in a final report to NIHR published in 2019 and now available in NIHR Journals Library. Additionally, the results have been presented and discussed at conferences attended by researchers, professionals and service users and prompted considerable interest and discussion about the implications of the results for the services they provide and use.

Other researchers have shown interest in using the linked database, So far, one project, ‘Tracking the Impact of Gestational Age on Health, Educational and Economic Outcomes: a Longitudinal Record Linkage Study’ (TIGAR) has now been completed, funded by the MRC and led by the University of Oxford. This analysed hospital admissions in childhood among children born in 2005 and 2006 by gestational age at birth. In addition to confirming that children born preterm are at much higher risk than others, of hospital admission in childhood, it showed raised rates of admission among the very much larger numbers of children born late preterm at 36 weeks or early term at 37-38 weeks of gestation. This is relevant to decisions about induction policies at these gestational ages.

A researcher at the Institute of Child Health, University College London (UCL) obtained ONS approval for linkage of data about births around 2011 to the census. This individual then successfully applied for ethics and Section 251 permission and funding from the MRC and for a Data Sharing Agreement (DARS-NIC-23456-C3J1D) with NHS England approving linkage of the database to Census 2011 data for mothers who gave birth during the year preceding and following the census date. The researcher from UCL also has permission for linkage to postcode-level data on air pollution and building characteristics. The linkage is being done by the Office for National Statistics and the linked dataset was provided to UCL without identifiers. The Air Pollution, housing and respiratory tract Infections in Children: National Birth Cohort Study (PICNIC) is investigating the association between housing, air pollution and respiratory infections in children. City, University of London is a joint controller on DARS-NIC-23456-C3J1D.

Due to resource issues, the applicant has not been able to analyse the data as much as they had hoped due to resource constraints and the COVID-19 Pandemic. An academic paper was recently published in BJM journals in June 2023, however, it is too early to recognise the benefits as a result of this paper.

City, University of London requires continuing access to previously provided HES data. These data were provided for the purpose of maintaining a research database which can potentially be accessed by authorised researchers using the secure environment of the Office for National Statistics, ONS Secure Research Service (SRS), formerly known as the Virtual Microdata Laboratory (VML), subject to obtaining the required ethics and section 251 approvals. Permission for this was given explicitly in CAG-08(b)/2014 which also covered planned analyses. No new data are requested in this agreement. It includes the same analyses as the previous agreement. It was not possible to complete these during the funding period for the previous project, because of delays in data access, so further funding has been obtained to continue the work.

All the data provided to the project had already been collected through the processes of civil registration, birth notification, compiling the Hospital Episode Statistics or perinatal audit by the now disbanded Centre for Maternal and Child Enquiries. There was no primary data collection. In selecting variables for linking and analysis, every attempt was made to strike a balance between the need to request the key data items needed for analysis and requesting data items which were crucial to enabling the linked dataset to be used by other researchers. At a later stage in the series of projects, it was necessary to request a few further data items in order to do the linkage and answer the research questions.

The database was created as a result of three collaborative projects led by City, University of London over a period of more than ten years the first of these funded by City University RAE Development Fund involved pilot linkage of birth registration records to birth notification records, previously known as the NHS Numbers for Babies (NN4B) records. Birth registration records were already linked by the Office for National Statistics (ONS) to death registration records for babies who died. The pilot was successful and ONS mainstreamed the linkage for the years 2006 onwards. Since then, the linked records have been used for publications and research and the data have been provided already being for further linkage to other.

In the second project, funded by the Medical Research Council (MRC), the already linked birth registration and notification data were further linked to HES Maternity delivery and birth records and permission was given to hold these as a database. This database adds value to the HES data by adding further data items from birth registration and notification and more complete data for important data items, notably birthweight and gestational age where HES are incomplete. It was created to enable ‘analyses relating to inequalities in the outcome of pregnancy and information for service users about the outcome of midwifery, obstetric and neonatal and related health care’.

As part of the third project, -‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS, funded by NIHR, there was further linkage of birth and delivery records to admitted patient care records relating to any subsequent admissions of these mothers and children to hospital and a relational database was constructed to hold the linked records. Funding has been secured from ESRC for a follow on project, ‘Implications of time of day and day f week for the outcome of birth’ which will use the same data to do some of the uncompleted analyses from the third project.

These are justified under Article 9.2(j) of the General Data Protection Regulation as being of substantial public health interest and scientific purposes as evidenced by consultations held with service users as part of the research and in the extent of media coverage when the analyses have been published.

Under this Data Sharing Agreement, use of the data is approved for two projects led by City, University of London. These are the original third project, entitled ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’ and the follow-on project, ‘Implications of time of day and day of the week for the outcome of birth’. This follow-on project is made up of analyses which were approved as part of the earlier project, but remained uncompleted at the end of the funding period. The database was originally established in its current form as part of the project, extending and updating work done in preceding data linkage projects.

Taken as a whole these analyses were designed to be undertaken in the public interest under Article 6(1)(e) of the General Data Protection Regulation in response to concern about the possibility of hourly and daily differences in the quality and safety of maternity and related care. Analyses since the 1970s have shown that maternity outcomes have apparently differed by day of the year, day of the week and time of day. The project aimed to understand the reasons for this. Public and patient involvement is a key part of this work and consultations with service users showed considerable interest and support along with confidence that individuals were not going to be identified in a database of over seven million births held in a secure setting.

City, University of London is the Data Controller and responsible for managing access to this database and the purpose(s) for which the data may be used. It has the necessary ethics and Section 251 approvals for establishing and maintaining the database. City, University of London may only grant access to the research database which City University of London have produced to researchers who have the necessary ethics and Section 251 approvals for purposes approved by NHS Digital. It will ensure that data access is restricted to ONS personnel - defined as “all employees, agents and contractors of the Data Recipient who may have access to the Data” – or to personnel employed by an organisation named as a Data Processor in an active Data Sharing Agreement for the purposes defined in that Agreement. For clarity, City, University of London is the Data Controller and also processes the data.

This Data Sharing Agreement covers only the data supplied by NHS Digital; not the ONS data to which it is linked.

The aims of the project were to compare daily, weekly and yearly variations in numbers of spontaneous and other births by time, day and season of birth and to compare variations in rates of adverse outcome. The project aimed to answer the following questions:

1. How do numbers of births vary according to time of day, day of the week and time of year of birth and how does this relate to methods of onset of labour and delivery and multiplicity?

2. Subject to the availability of data, how do patterns of birth vary between maternity services in relation to variations in medical and midwifery staffing, patterns of intervention and size of unit?

3. How does the outcome of pregnancy in terms of rates of cause specific intra-partum stillbirth and neonatal and infant mortality rates and rates of morbidity recorded at birth and at hospital admission in the first year of life vary according to time of day, day of the week and time of year in relation to gestational age, and intervention in the onset of labour and delivery?

4. Have the patterns observed changed over the years 2005 onwards?

The project aimed to inform decision-making by providing information about how numbers of births in England and Wales vary by time of day, day of week and day of the year.

It analysed separately births before term and those after full term pregnancies. In addition it is took account of whether labour and delivery occurred spontaneously or whether their timing was affected by inducing labour, or by undertaking either a planned caesarean section or an emergency caesarean section during labour.

It produced answers to questions 1 and 4 but because of delays in data access, there was not time to answer questions 2 and 3 under the previous agreement within the time period funded by NIHR. Further funding has now been secured from the ESRC and this new agreement will make it possible to answer outstanding questions. In particular, the rates of death and severe problems in babies or their mothers will be analysed in relation to the factors outlined above. This is a question of considerable public concern.

The results will be related to maternity units’ and NHS trusts’ overall rates of induction and caesarean section. As far is feasible within the limitations of data quality and completeness, it will draw on available information about their overall rates of midwifery and obstetric staffing although work done to date suggests that the extent to which it can do so may be limited. It is hoped that information about timing of birth can be used by the NHS to inform planning both levels of staffing in terms of midwives and obstetricians and in detailed rostering, with the aim of trying to match the numbers of women in labour and giving birth and the numbers of midwives available and the availability of obstetric support should complications arise.

The University of Oxford was doing preparatory work before applying for an extract of the pseudonymised linked dataset for the purpose of a separate project called ‘Tracking the Impact of Gestational Age on Health, Educational and Economic outcomes: a Longitudinal Record Linkage Study (TIGAR)’. This has now been agreed by NHS Digital under a separate Data Sharing Agreement, reference DARS-NIC-09637-Y8T1N.

In advance of that application for approval, the TIGAR study's Principal Investigator and a co-investigator, both of whom are employed by the University of Oxford at the National Perinatal Epidemiology Unit (NPEU), had been supporting the personnel from City, University of London by undertaking quality assurance and data cleaning exercises to assure and improve the quality and completeness of matching the birth records with the HES records including subsequent admissions. Under the previous Data Sharing Agreement (DARS-NIC-10094-P6P4B-v6.7), the principal investigator and co-investigator of the TIGAR project were the only personnel from the University of Oxford who were permitted to access the data and access was for the purpose of quality assurance and data cleaning.

To clarify, researchers on the TIGAR project led by the University of Oxford are no longer involved in this project. The work they did to quality control the data they went on to use has finished and the relevant data, a subset of the whole cohort were transferred to their project area, where they were analysed under their Data Sharing Agreement. This project has now finished and ONS is currently deleting these data.

All individuals accessing the data work under the supervision of City, University of London under conditions defined by ONS when carrying out the work, using ONS’ secure facilities that are required when handling identifiable data. No record level data may be accessed outside of the secure environment of the SRS.

The output of the data linkage and subsequent quality assurance was the creation of the research database which is stored within ONS, accessed only via the SRS subject to the controls outlined above. The database was created as an output of the previous project. Some of the quality assurance was undertaken as part of the NIHR-funded project and further quality assurance was undertaken by the two TIGAR researchers from the University of Oxford. There is still further quality assurance work to be done however this will be done solely by City, University of London. This quality assurance was included in the Secondary Data Analysis Initiative (SDAI) funded follow-on project but it has yet to be done.

From the NIHR-funded project, ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’, the outputs listed below have been delivered or are expected. Further articles are expected from the SDAI-funded follow-on project and are listed below.

City, University of London submitted four articles to peer reviewed journals and a final report to the National Institute for Health Research (NIHR). Two articles have been published by BMJ Open, a weekly peer reviewed medical journal and a further article was published in PLOS1, a peer reviewed open access scientific journal. The fourth was rejected and needs revision before resubmission. NIHR has published the final report in its online journal. City, University of London and its collaborators have also given oral and poster presentations at a number of conferences, as shown on the list below. Further articles will be written, based on work already partly completed and the further analyses which were subsequently funded.

City, University of London will write and submit a further article summarising findings to Significance, the Royal Statistical Society’s magazine which aims to popularise statistics. It was intended that this article plus the revised article mentioned above would have been submitted for publication 2021 but these were delayed by the coronavirus pandemic. On the other hand, at a time early in the pandemic, City, University of London took the opportunity to write an article on public engagement work for a special issue of the International Journal of Population Data Linkage.

The study team planned to submit at least three articles to peer reviewed journals based on the SDAI funded work, one on the outcome of births by time of day and day of the week, one on differences between maternity units and one on the linkage and analysis of data about births in Wales. The article on neonatal mortality by time of day and day of the week is at advanced draft stage and nearly ready for submission for publication. The work in it has formed the basis of two abstracts which have been accepted for presentation at conferences in September 2022. The work on differences between maternity units is still at an early stage and more work is needed. Although descriptive analyses of the data for Wales have been undertaken, statistical modelling is needed to complete the work. It is not possible to set targets at present as work was severely delayed by data access problems at the beginning of the pandemic and further funding will be needed to finish the work in addition to a renewal of this Data Sharing Agreement.

When each of these articles are accepted, the study team will continue to work with City’s press office to maximise coverage. The article on the timing of birth published in 2018 was well reported in the national media and there were over 370 press reports.

Opportunities will be taken to continue to present findings at professional conferences and the team aims to contribute to publications, such as the research summaries included on the Royal College of Midwives magazine, ‘Midwives’.

Public and Patient Involvement is at the heart of this project and reaches well beyond the minimum required by funders. It was originally intended that results in the form of aggregated statistics, which may have included some sub-national results with small numbers suppressed, would be provided to the National Childbirth Trust (NCT) for its work in providing services and materials to prospective and actual parents. NCT subsequently dropped out of the project and City, University of London are now engaging with National Maternity Voices instead, using different approaches (but still within the boundaries and purpose of the existing protocol and previous Data Sharing Agreement)..

A member of the project team, with extensive experience of research engagement, will disseminate the findings to parent representatives and ‘patient’ advocates serving on maternity services liaison committees and labour ward forums with the aim of highlighting research findings and service users’ views and priorities to clinical managers and commissioners. In the follow on project, the person concerned, who previously was employed by NCT, has been employed by City, University of London.

NCT also involves its members in representing the views of service users to the maternity services and also participating in research projects to represent users’ views. Three meetings of NCT members and others who are service user representatives on Maternity Services Liaison Committees and Maternity Voices Partnerships to do this were held in relation to the third project. They were useful in exploring service users’ concerns about possible temporal variations in the safety of birth, including positive and negative implications of birth at night and at weekends. Two more were planned as part of the ESRC-funded follow-on project, but because of the coronavirus pandemic, they were replaced with online engagement activities which had the same aim. An article will be submitted for publication to describe the innovative approaches developed for this work. No one involved in this aspect of the project has access to individual service users’ records.

The following outputs have been produced to date:

Outputs from NIHR funded work

Articles in peer reviewed journals:

Dattani N, Macfarlane A. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005-2014: methods. A population-based birth cohort study. BMJ Open 2018;8:e017897. doi:10.1136/ bmjopen-2017-017897

Harper G. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005–2014: Quality assurance of linkage of routine data for singleton and multiple births. BMJ Open Mar 2018, 8 (3) e017898; DOI: 10.1136/bmjopen-2017-017898

Martin P, Mario Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N, Macfarlane A. Timing of singleton births by onset of labour and mode of birth in NHS maternity units in England, 2005 – 2014: a study of linked birth registration, birth notification, and hospital episode data. PLoS ONE 2018 Jun 14;13(6): e0198183. https:/doi.org/10.1371/journal.pone.198183. . eCollection 2018.

To be revised and resubmitted:

Dattani N. Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Submitted to Birth. Rejected with suggestions for a revised article which will be redrafted and submitted.

Final report to NIHR:

Macfarlane A, Dattani N, Gibson R, Harper G, Martin P, Scanlon M, Newburn M, Cortina-Borja M. Births and their outcomes by time, day and year: a retrospective birth cohort data linkage study. Health Serv Deliv Res 2019;7(18).

Other articles:

Rapid response to BMJ ‘Association between day of delivery and obstetric outcomes: observational study’ was published as a BMJ Rapid Response 25 November 2015. URL: http://www.bmj.com/content/351/bmj.h5774/rr-7

Macfarlane A. Day and time of birth and mode of onset and birth. Research Summary 3. Practice: Research summary 3. Midwives / Winter 2018; 34. cm.org.uk/midwives

Birth cohort data linkage study. https://www.adruk.org/our-mission/our-impact/article/birth-cohort-data-linkage-study-228/

Birth and its outcome by time, day and year: a birth cohort data linkage study. School of Health Sciences, City, University of London. https://www.ons.gov.uk/file?uri=/aboutus/whatwedo/statistics/requestingstatistics/approvedresearcherscheme/arlistjan2020forpublication.xls

Oral presentations:

Dattani N, Macfarlane A, Datta-Nemdharry P. Using data linkage to create a national database of birth and maternity data. Presentation at Royal Statistical Society Conference, Sheffield, September 2014.

Macfarlane AJ. ‘Care.data’: Bungled opportunity or unjustified intrusion? Invited presentation to Royal Statistical Society meeting. October 7 2014.

Macfarlane A, Dattani N. Using linkage of administrative data to build a national database for analysis of birth and its outcome in England and Wales. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Quality Assuring Linked Birth Registration and Hospital Episode Statistics Delivery Records – results and lessons learned. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Insights on Third Party Linkage and Data Quality from Quality Assuring Linked Birth Registrations and HES Delivery Records in England 2005 to 2014. Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Macfarlane A, Martin P, Cortina-Borja M. Dattani N, Harper G, Newburn M. Gibson R. ‘A time to be born’? Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Martin P, Cortina-Borja M, Dattani N, Harper G, Gibson R, Newburn M, Dodwell M, Macfarlane A. Variations in numbers of births by day of the week in relation to onset of labour and mode of giving birth, England 2005-2014. Oral presentation at Royal Statistical

Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Cortina Borja M, in collaboration with Macfarlane A, Dattani N, Dodwell M, Gibson R, Harper G, Martin P, Newburn M. Modelling numbers of births by day of the week in relation to onset of labour and mode of giving birth in England 2005–2014. Talk to RSS South West local group, Plymouth University, 20th February 2019.

Macfarlane A, Dattani N. Building a birth cohort of births and their outcome in England and Wales using linkage of administrative data. Oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Macfarlane A, Dattani N. Analysis of births England and Wales by time of day and day of the week and place of birth using linked administrative data. Rapid fire presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Conference posters:

Dattani N, Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Macfarlane A, Dattani N. Using data linkage to build a national database of data about birth and its outcome for policy analysis in England and Wales. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Harper G, Macfarlane A, Dattani N, Dodwell M, Newburn M, Gibson R, Cortina-Borja M, Martin P. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Poster presented at the International Population Data Linkage Conference, Swansea, Wales, 24-26 August 2016.

Macfarlane A, Dattani N, Harper G, Cortina-Borja M, Martin P, Gibson R, Dodwell M, Newburn M. Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for midwifery care. Poster presented at the Royal College of Midwives Annual Conference. Harrogate, October 19-20 2016.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. ‘A time to be born?’ Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England. Winner of the Scientific Review Team Prize.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. Births: the weekly cycle. Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England

Oral presentations

Coathup V, Macfarlane A, Quigley M. Evaluating record linkage of birth registration and notification records to Maternity Hospital Episode Statistics and childhood hospital readmissions: Singleton births in 2005 and 2006 across England. Oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Outputs from ESRC SDAI-funded work

Articles in peer-reviewed journals:

Newburn M, Scanlon M, Plachcinski R, Macfarlane A. Involving service users in the Birth Timing Project, a data linkage study analysing the timing of births and their outcomes. International Journal of Population Data Science (2020) 5; 3 :1366. https://doi.org/10.23889/ijpds.v5i3.1366

To be submitted shortly:

Carty L, Cortina-Borja M, Plachcinski R, Grollman C, Macfarlane A. Neonatal mortality in NHS maternity units by timing of birth and mode of birth: a retrospective linked cohort study.

Oral presentations:

Miranda Scanlon, Mary Newburn, [Nirupa Dattani], Rachel Plachcinski, Alison Macfarlane. Public involvement and engagement with an analysis of births in different settings by time of day and day of the week using linked data. Oral presentation at the 15th International Normal Labour and Birth Research Conference, India. December 2020. Winner of the first prize for oral presentation. https://youtu.be/FEU6R1xpNUA

Miranda Scanlon, Mary Newburn. Presentation based on the above to the KCL Maternal Health Systems and Policy Research Group Meeting 15 March 2021.

Scanlon M, Newburn M, Plachcinski R, Macfarlane A. Involving the public with an analysis of daily, weekly, and yearly cycles of births using linked data. Online Presentation in ONS Research Excellence Series. May 17 2022.

Plachcinski R. Invited plenary speaker. International Population Data Linkage Conference, Edinburgh, September 7-9 2022.

Carty L, Cortina-Borja M, Rachel Plachcinski, Grollman C, Macfarlane A. Neonatal mortality in NHS maternity units by timing of birth and method of delivery: a retrospective linked cohort study. Accepted for oral presentation. International Population Data Linkage Conference, Edinburgh, September 7-9 2022.

Carty L, Cortina-Borja M, Rachel Plachcinski, Grollman C, Macfarlane A. Is ‘out of hours’ birth dangerous? a retrospective linked cohort study. Accepted for rapid fire presentation. Royal Statistical Society International Conference, Aberdeen, September 12-15, 2022.

July 2022 (v7) rewrite:

The establishment of the research database for which City, University of London have Health Research Authority approval, permits additional research into maternity and its outcome. This database provides a more complete resource than any of the datasets individually by combining birth registration, birth notification and HES. This has enhanced HES by linking it to a fuller and more complete dataset and also adding variables which are not in Maternity HES.

The database was not updated with more recent data for the ESRC-funded follow-on project. This is because the aim of this project was to analyse the data already held and no new data were requested.

Despite the lack of updates, as the methods have been established, there is a potential to continually update the linkage to enable this work to reach its full potential by ‘mainstreaming’ it, so that is updated annually to produce timely linked data for both research and the production of national statistics. Administrative Data Research UK, which has been established to transform the way researchers access public sector data in the countries of the UK by joining up the data and facilitating safe and secure access to create a resource which will give insights into how City, University of London’s society and economy function is keen for this to happen. Discussions have already started with the Office for National Statistics about enabling this.

The establishment of the database in its current form was funded as part of the NIHR-funded third project ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’. The aim of the parts of the project completed was to provide a better understanding of daily, weekly and seasonal variations in patterns of birth and this has been achieved. The next steps is to ascertain the impact of these differences on variations observed in outcome, in order to assess the extent to which these reflect selection and to inform improvements in the planning of maternity services.

The analyses done in this project show the extent of daily and weekly variations in numbers of singleton births and these have implications for the planning and staffing of maternity services. This and the other work done has been described in detail in a final report to NIHR published in 2019 and now available in NIHR Journals Library. Additionally, the results have been presented and discussed at conferences attended by researchers, professionals and service users and prompted considerable interest and discussion about the implications of the results for the services they provide and use.

Further research using the linked dataset:

Other researchers have shown interest in using the linked database, as envisaged in the Section 251 approval. So far, one project, ‘Tracking the Impact of Gestational Age on Health, Educational and Economic outcomes: a Longitudinal Record Linkage Study’ (TIGAR) has now been completed, funded by the MRC and led by the University of Oxford. This analysed hospital admissions in childhood among children born in 2005 and 2006 by gestational age at birth. In addition to confirming that children born preterm are at much higher risk than others, of hospital admission in childhood, it showed raised rates of admission among the very much larger numbers of children born late preterm at 36 weeks or early term at 37-38 weeks of gestation. This is relevant to decisions about induction policies at these gestational ages.

A researcher at the Institute of Child Health, University College London (UCL) obtained ONS approval for linkage of data about births around 2011 to the census. She then successfully applied for ethics and Section 251 permission and funding and for a Data Sharing Agreement with NHS Digital approving linkage of the database to Census 2011 data for mothers who gave birth during the year preceding and following the census date. She also has permission for linkage to postcode level data on air pollution and building characteristics. The linkage is being done by the Office for National Statistics and the linked dataset will be provided to UCL without identifiers. The project will investigate association between housing, air pollution and respiratory infections in children. ESRC funding has been obtained to use these and other linkages to produce research ready datasets. The NIHR-funded project had the support of the Chief Executive of the Royal College of Midwives and of the Royal College of Obstetricians and Gynaecologists, both of which provided letters of support.

City, University of London requires continuing access to previously provided HES data. These data were provided for the purpose of maintaining a research database which can potentially be accessed by authorised researchers using the secure environment of the Office for National Statistics, ONS Secure Research Service (SRS), formerly known as the Virtual Microdata Laboratory (VML), subject to obtaining the required ethics and section 251 approvals. Permission for this was given explicitly in CAG-08(b)/2014 which also covered planned analyses. No new data are requested in this agreement. It includes the same analyses as the previous agreement. It was not possible to complete these during the funding period for the previous project, because of delays in data access, so further funding has been obtained to continue the work.

All the data provided to the project had already been collected through the processes of civil registration, birth notification, compiling the Hospital Episode Statistics or perinatal audit by the now disbanded Centre for Maternal and Child Enquiries. There was no primary data collection. In selecting variables for linking and analysis, every attempt was made to strike a balance between the need to request the key data items needed for analysis and requesting data items which were crucial to enabling the linked dataset to be used by other researchers. At a later stage in the series of projects, it was necessary to request a few further data items in order to do the linkage and answer the research questions.

The database was created as a result of three collaborative projects led by City, University of London over a period of more than ten years the first of these funded by City University RAE Development Fund involved pilot linkage of birth registration records to birth notification records, previously known as the NHS Numbers for Babies (NN4B) records. Birth registration records were already linked by the Office for National Statistics (ONS) to death registration records for babies who died. The pilot was successful and ONS mainstreamed the linkage for the years 2006 onwards. Since then, the linked records have been used for publications and research and the data have been provided already being for further linkage to other.

In the second project, funded by the MRC, the already linked birth registration and notification data were further linked to HES Maternity delivery and birth records and permission was given to hold these as a database. This database adds value to the HES data by adding further data items from birth registration and notification and more complete data for important data items, notably birthweight and gestational age where HES are incomplete. It was created to enable ‘analyses relating to inequalities in the outcome of pregnancy and information for service users about the outcome of midwifery, obstetric and neonatal and related health care’.

As part of the third project, -‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS, funded by NIHR, there was further linkage of birth and delivery records to admitted patient care records relating to any subsequent admissions of these mothers and children to hospital and a relational database was constructed to hold the linked records. Funding has been secured from ESRC for a follow on project, ‘Implications of time of day and day f week for the outcome of birth’ which will use the same data to do some of the uncompleted analyses from the third project.

These are justified under Article 9.2(j) of the General Data Protection Regulation as being of substantial public health interest and scientific purposes as evidenced by consultations held with service users as part of the research and in the extent of media coverage when the analyses have been published.

Under this Data Sharing Agreement, use of the data is approved for two projects led by City, University of London. These are the original third project, entitled ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’ and the follow-on project, ‘Implications of time of day and day of the week for the outcome of birth’. This follow-on project is made up of analyses which were approved as part of the earlier project, but remained uncompleted at the end of the funding period. The database was originally established in its current form as part of the project, extending and updating work done in preceding data linkage projects.

Taken as a whole these analyses were designed to be undertaken in the public interest under Article 6(1)(e) of the General Data Protection Regulation in response to concern about the possibility of hourly and daily differences in the quality and safety of maternity and related care. Analyses since the 1970s have shown that maternity outcomes have apparently differed by day of the year, day of the week and time of day. The project aimed to understand the reasons for this. Public and patient involvement is a key part of this work and consultations with service users showed considerable interest and support along with confidence that individuals were not going to be identified in a database of over seven million births held in a secure setting.

City, University of London is the Data Controller and responsible for managing access to this database and the purpose(s) for which the data may be used. It has the necessary ethics and Section 251 approvals for establishing and maintaining the database. City, University of London may only grant access to the research database which City University of London have produced to researchers who have the necessary ethics and Section 251 approvals for purposes approved by NHS Digital. It will ensure that data access is restricted to ONS personnel - defined as “all employees, agents and contractors of the Data Recipient who may have access to the Data” – or to personnel employed by an organisation named as a Data Processor in an active Data Sharing Agreement for the purposes defined in that Agreement.

This Data Sharing Agreement covers only the data supplied by NHS Digital; not the ONS data to which it is linked.

The aims of the project were to compare daily, weekly and yearly variations in numbers of spontaneous and other births by time, day and season of birth and to compare variations in rates of adverse outcome. The project aimed to answer the following questions:

1. How do numbers of births vary according to time of day, day of the week and time of year of birth and how does this relate to methods of onset of labour and delivery and multiplicity?

2. Subject to the availability of data, how do patterns of birth vary between maternity services in relation to variations in medical and midwifery staffing, patterns of intervention and size of unit?

3. How does the outcome of pregnancy in terms of rates of cause specific intra-partum stillbirth and neonatal and infant mortality rates and rates of morbidity recorded at birth and at hospital admission in the first year of life vary according to time of day, day of the week and time of year in relation to gestational age, and intervention in the onset of labour and delivery?

4. Have the patterns observed changed over the years 2005 onwards?

The project aimed to inform decision-making by providing information about how numbers of births in England and Wales vary by time of day, day of week and day of the year.

It analysed separately births before term and those after full term pregnancies. In addition it is took account of whether labour and delivery occurred spontaneously or whether their timing was affected by inducing labour, or by undertaking either a planned caesarean section or an emergency caesarean section during labour.

It produced answers to questions 1 and 4 but because of delays in data access, there was not time to answer questions 2 and 3 under the previous agreement within the time period funded by NIHR. Further funding has now been secured from the ESRC and this new agreement will make it possible to answer outstanding questions. In particular, the rates of death and severe problems in babies or their mothers will be analysed in relation to the factors outlined above. This is a question of considerable public concern.

The results will be related to maternity units’ and NHS trusts’ overall rates of induction and caesarean section. As far is feasible within the limitations of data quality and completeness, it will draw on available information about their overall rates of midwifery and obstetric staffing although work done to date suggests that the extent to which it can do so may be limited. It is hoped that information about timing of birth can be used by the NHS to inform planning both levels of staffing in terms of midwives and obstetricians and in detailed rostering, with the aim of trying to match the numbers of women in labour and giving birth and the numbers of midwives available and the availability of obstetric support should complications arise.

The University of Oxford was doing preparatory work before applying for an extract of the pseudonymised linked dataset for the purpose of a separate project called ‘Tracking the Impact of Gestational Age on Health, Educational and Economic outcomes: a Longitudinal Record Linkage Study (TIGAR)’. This has now been agreed by NHS Digital under a separate Data Sharing Agreement, reference DARS-NIC-09637-Y8T1N.

In advance of that application for approval, the TIGAR study's Principal Investigator and a co-investigator, both of whom are employed by the University of Oxford at the National Perinatal Epidemiology Unit (NPEU), have been supporting the personnel from City, University of London by undertaking quality assurance and data cleaning exercises to assure and improve the quality and completeness of matching the birth records with the HES records including subsequent admissions. For clarity, under this Data Sharing Agreement, the principal investigator and co-investigator of the TIGAR project are the only personnel from the University of Oxford who are permitted to access the data and access is for the purpose of quality assurance and data cleaning. Although the bulk of this work has now been completed, these personnel may still need occasional access for checking purpose while writing this work up for publication. No other analyses of the data may be undertaken for the purpose of the TIGAR study under this Agreement and no other individuals from the University of Oxford may be granted access to the data.

All individuals accessing the data work under the supervision of City, University of London under conditions defined by ONS when carrying out the work, using ONS’ secure facilities that are required when handling identifiable data. No record level data may be accessed outside of the secure environment of the SRS.

Access to identifiers is restricted to these researchers from the University of Oxford and the individuals working at the linkage and data cleaning stage only.

The output of the data linkage and subsequent quality assurance was the creation of the research database which is stored within ONS, accessed only via the SRS subject to the controls outlined above. The database was created as an output of the previous project. Some of the quality assurance was undertaken as part of the project and further quality assurance was undertaken by the two TIGAR researchers from the University of Oxford. There is still further quality assurance work to be done and quality assurance is included in the follow-on project.

From the project, ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’, the outputs listed below have been delivered or are expected. Further articles are expected from the follow-on project.:

City, University of London submitted four articles to peer reviewed journals and a final report to the National Institute for Health Research (NIHR). Two articles have been published by BMJ Open, a weekly peer reviewed medical journal and a further article was published in PLOS1, a peer reviewed open access scientific journal, and the fourth is being revised before resubmission. NIHR has published the final report in its online journal. City, University of London has also given oral and poster presentations at a number of conferences, as shown on the list below. Further articles will be written, based on work already partly completed and the further analyses which have now been funded.

City, University of London will write and submit a further article summarising findings to Significance, the Royal Statistical Society’s magazine which aims to popularise statistics. This will be submitted for publication within the next year.

Once the further analyses are complete, results in the form of aggregated statistics, which may include some sub-national results with small numbers suppressed, graphs and diagrams and the outputs of statistical analyses will be written up as further articles for submission to peer reviewed journals.

The study team plan to submit at least three articles to peer reviewed journals, one on the outcome of births by time of day and day of the week, one on differences between maternity units and one on the linkage and analysis of data about births in Wales. When they are accepted, the study team will work with City’s press office to maximise coverage. A recent article on the timing of birth was reported in the national media and to date there have been over 370 press reports.

Opportunities will be to present findings at professional conferences and aim to contribute to publications, such as the research summaries included on the Royal College of Midwives magazine, ‘Midwives’.

Public and Patient Involvement is at the heart of this project and reaches well beyond the minimum required by funders. Results in the form of aggregated statistics, which may include some sub-national results with small numbers suppressed, will be provided to the National Childbirth Trust (NCT) for its work in providing services and materials to prospective and actual parents.

A member of the project team, with extensive experience of research engagement, will disseminate the findings to parent representatives and ‘patient’ advocates serving on maternity services liaison committees and labour ward forums with the aim of highlighting research findings and service users’ views and priorities to clinical managers and commissioners. In the follow on project, the person concerned will be employed by City, University of London.

NCT also involves its members in representing the views of service users to the maternity services and also participating in research projects to represent users’ views. Three meetings of NCT members and others who are service user representatives on Maternity Services Liaison Committees and Maternity Voices Partnerships to do this were held in relation to the third project. They were useful in exploring service users’ concerns about possible temporal variations in the safety of birth, including positive and negative implications of birth at night and at weekends. Two more are planned as part of the follow-on project. No one involved in this aspect of the project has access to individual service users records.

The following outputs have been produced to date:

Articles in peer reviewed journals:

Dattani N, Macfarlane A. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005-2014: methods. A population-based birth cohort study. BMJ Open 2018;8:e017897. doi:10.1136/ bmjopen-2017-017897

Harper G. Linkage of Maternity Hospital Episode Statistics data to birth registration and notification records for births in England 2005–2014: Quality assurance of linkage of routine data for singleton and multiple births. BMJ Open Mar 2018, 8 (3) e017898; DOI: 10.1136/bmjopen-2017-017898

Martin P, Mario Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N, Macfarlane A. Timing of singleton births by onset of labour and mode of birth in NHS maternity units in England, 2005 – 2014: a study of linked birth registration, birth notification, and hospital episode data. PLoS ONE 13(6): e0198183. https:/doi.org/10.1371/journal.pone.198183.

Dattani N. Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Submitted to Birth. Rejected with suggestions for a revised article which is being drafted and submitted.

Other articles

Macfarlane A. Day and time of birth and mode of onset and birth. Research Summary 3. Practice: Research summary 3. Midwives / Winter 2018; 34. cm.org.uk/midwives

Final report to NIHR

Macfarlane A, Dattani N, Gibson R, Harper G, Martin P, Scanlon M, Newburn M, Cortina-Borja M. Births and their outcomes by time, day and year: a retrospective birth cohort data linkage study. Health Serv Deliv Res 2019;7(18).

Rapid response to BMJ

‘Association between day of delivery and obstetric outcomes: observational study’ was published as a BMJ Rapid Response 25 November 2015. URL: http://www.bmj.com/content/351/bmj.h5774/rr-7

Oral presentations:

Dattani N, Macfarlane A, Datta-Nemdharry P. Using data linkage to create a national database of birth and maternity data. Presentation at Royal Statistical Society Conference, Sheffield, September 2014.

Macfarlane AJ. ‘Care.data’: Bungled opportunity or unjustified intrusion? Invited presentation to Royal Statistical Society meeting. October 7 2014.

Macfarlane A, Dattani N. Using linkage of administrative data to build a national database for analysis of birth and its outcome in England and Wales. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Quality Assuring Linked Birth Registration and Hospital Episode Statistics Delivery Records – results and lessons learned. Presentation at the Administrative Data Research Network Conference, Edinburgh, June 1-2 2017.

Harper G. Insights on Third Party Linkage and Data Quality from Quality Assuring Linked Birth Registrations and HES Delivery Records in England 2005 to 2014. Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Macfarlane A, Martin P, Cortina-Borja M. Dattani N, Harper G, Newburn M. Gibson R. ‘A time to be born’? Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Martin P, Cortina-Borja M, Dattani N, Harper G, Gibson R, Newburn M, Dodwell M, Macfarlane A. Variations in numbers of births by day of the week in relation to onset of labour and mode of giving birth, England 2005-2014. Oral presentation at Royal Statistical Society International Conference, University of Strathclyde, Glasgow, September 4-7 2017.

Cortina Borja M, in collaboration with Macfarlane A, Dattani N, Dodwell M, Gibson R, Harper G, Martin P, Newburn M. Modelling numbers of births by day of the week in relation to onset of labour and mode of giving birth in England 2005–2014. Talk to RSS South West local group, Plymouth University, 20th February 2019.

Macfarlane A, Dattani N. Building a birth cohort of births and their outcome in England and Wales using linkage of administrative data. Accepted for oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Macfarlane A, Dattani N. Analysis of births England and Wales by time of day and day of the week and place of birth using linked administrative data. Accepted for rapid fire presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Coathup V, Macfarlane A, Quigley M. Evaluating record linkage of birth registration and notification records to Maternity Hospital Episode Statistics and childhood hospital readmissions: Singleton births in 2005 and 2006 across England. Accepted for oral presentation at the 4th International Conference on Administrative Data Research, Cardiff, Wales, 9-11 December 2019.

Conference posters:

Dattani N, Macfarlane A. Analysis of births at home in England and Wales by time of day and day of the week using linked administrative data. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Macfarlane A, Dattani N. Using data linkage to build a national database of data about birth and its outcome for policy analysis in England and Wales. Poster presented at Farr Institute International Conference, University of St Andrews, 26 – 28 August 2015.

Harper G, Macfarlane A, Dattani N, Dodwell M, Newburn M, Gibson R, Cortina-Borja M, Martin P. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Analysing the daily, weekly and yearly cycles of births and their implications for the NHS using linked data. Poster presented at the International Population Data Linkage Conference, Swansea, Wales, 24-26 August 2016.

Macfarlane A, Dattani N, Harper G, Cortina-Borja M, Martin P, Gibson R, Dodwell M, Newburn M. Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for midwifery care. Poster presented at the Royal College of Midwives Annual Conference. Harrogate, October 19-20 2016.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. ‘A time to be born?’ Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England. Winner of the Scientific Review Team Prize.

Macfarlane A, Martin P, Cortina-Borja M, Newburn M, Harper G, Gibson R, Dodwell M, Dattani N. Births: the weekly cycle. Poster presented at the 12th International Normal Labour and Birth Research Conference, October 2nd to October 4th, 2017, Grange Over Sands, Cumbria, England

The establishment of the research database permits additional research into maternity and its outcome. This database provides a more complete resource than any of the datasets individually by combining birth registration, birth notification and HES. This has enhanced HES by linking it to a fuller and more complete dataset and also adding variables which are not in Maternity HES.

The database will not be updated with more recent data for the follow-on project. This is because the aim of this project is to analyse the data already held and no new data are requested. On the other hand, as the methods have been established, there is a potential to continually update the linkage to enable this work to reach its full potential by ‘mainstreaming’ it, so that is updated annually to produce timely linked data for both and the production of national statistics. Administrative Data Research UK, which has been established to transform the way researchers access public sector data in the countries of the UK by joining up the data and facilitating safe and secure access to create a resource which will give insights into how our society and economy function is keen for this to happen and discussions have already started with the Office for National Statistics about enabling this.

The establishment of the database in its current form was funded as part of the third project ‘Births and their outcome: analysing the daily, weekly and yearly cycles and their implications for the NHS’, which has yielded the following actual and expected benefits:

The aim of the parts of the project completed so far was to provide a better understanding of daily, weekly and seasonal variations in patterns of birth and this has been achieved. The next steps is to ascertain the impact of these differences on variations observed in outcome, in order to assess the extent to which these reflect selection and to inform improvements in the planning of maternity services.

The analyses done so far show the extent of daily and weekly variations in numbers of singleton births and these have implications for the planning and staffing of maternity services. This and the other work so far has been described in detail in a final report to NIHR published in 2019 and now available in NIHR Journals Library. Meanwhile, the results have been presented and discussed at conferences attended by researchers, professionals and service users and prompted considerable interest and discussion about the implications of the results for the services they provide and use.

Further research using the linked dataset:

Other researchers have shown interest in using the linked dataset. So far, one project, ‘Tracking the Impact of Gestational Age on Health, Educational and Economic outcomes: a Longitudinal Record Linkage Study’ (TIGAR) is well under way, funded by the MRC, as mentioned above.

A researcher at the Institute of Child Health, UCL obtained ONS approval for linkage of data about births around 2011 to the census. She then successfully applied for ethics and Section 251 permission and funding and for a Data Sharing Agreement DARS-NIC-234656-C3J1D-v0.11 approving linkage of the database to Census 2011 data for mothers who gave birth during the year preceding and following the census date and to postcode level data on air pollution and building characteristics. The linkage will be done by the Office for National Statistics and the linked dataset will be provided to UCL without identifiers. The project will investigate association between housing, air pollution and respiratory infections in children.

City, University of London has had exploratory discussions with other interested researchers.

The NIHR-funded project had the support of the Chief Executive of the Royal College of Midwives and of the Royal College of Obstetricians and Gynaecologists, both of which provided letters of support.