Publication, Part of Statistics on Women's Smoking Status at Time of Delivery: England
Statistics on Women's Smoking Status at Time of Delivery: England, Quarter 2, 2024-25
Official statistics
Inclusion of new comparative data from the Maternity Services Dataset (MSDS)
For 2024-25, comparative data using the Maternity Services Dataset (MSDS) is also presented using data submitted by Trusts. This is to help support decisions around the retirement of the Smoking at Time of Delivery data collection at the end of 2024-25.
19 September 2024 00:00 AM
Data quality statement
Purpose of document
This data quality statement aims to provide users with an evidence based assessment of quality of the statistical output included in this publication.
It reports against those of the nine European Statistical System (ESS) quality dimensions and principles appropriate to this output. The original quality dimensions are: relevance, accuracy and reliability, timeliness and punctuality, accessibility and clarity, and coherence and comparability; these are set out in Eurostat Statistical Law. However more recent quality guidance from Eurostat includes some additional quality principles on: output quality trade-offs, user needs and perceptions, performance cost and respondent burden, and confidentiality, transparency and security.
In doing so, this meets NHS England’s obligation to comply with the UK Statistics Authority (UKSA) code of practice for statistics and the following principles in particular:
- Trustworthiness pillar, principle 6 (Data governance) which states “Organisations should look after people’s information securely and manage data in ways that are consistent with relevant legislation and serve the public good.”
- Quality pillar, principle 3 (Assured Quality) which states “Producers of statistics and data should explain clearly how they assure themselves that statistics and data are accurate, reliable, coherent and timely.”
- Value pillar, principle 1 (Relevance to Users) which states “Users of statistics and data should be at the centre of statistical production; their needs should be understood, their views sought and acted upon, and their use of statistics supported.”
- Value pillar, principle 2 (Accessibility) which states “Statistics and data should be equally available to all, not given to some people before others. They should be published at a sufficient level of detail and remain publicly available.”
Relevance
This dimension covers the degree to which the statistical product meets user needs in both coverage and content.
Reducing smoking during pregnancy was one of the three national ambitions in the Tobacco Control Plan published back in July 2017. A new Tobacco and Vapes Bill was introduced in 2024 and it is anticipated that new strategies around reducing smoking in pregnancy are being developed under the new government. This report provides data to measure progress in reducing smoking in pregnancy.
SATOD v1 is used to populate indicator 2.3 in the Public Health Outcomes Framework (PHOF) (and was used in indicator 1.14 in the CCG Outcome Indicator Set (CCGOIS) until October 2022 when this dataset was decommissioned).
The report covers data provided by all Sub Integrated Care Board Locations (Sub-ICBs) for SATOD v1 and data provided by all Trusts who offer maternity services for SATOD v2 in England.
Accuracy and reliability
This dimension covers, with respect to the statistics, their proximity between an estimate and the unknown true value.
SATOD v1
In Quarter 4, revised data is accepted from Sub-ICBs for quarters 1, 2, and 3. The reports for Quarters 1,2 and 3 are therefore published on a provisional basis, with the final report being produced in Quarter 4.
Validation takes place at the point of entry. Further details on the validations carried out can be found in section B of the appendices.
DQ Table 1 of the Excel data tables contains data quality indicators for the latest quarter showing the percentage of women where the smoking status is not known, as well as the percentage difference compared to the average of the previous four quarters for:
- Maternities
- Women known to be smokers at time of delivery
- Women known to be non-smokers at time of delivery
In order to highlight any areas of concern and to encourage improvements, a Sub-ICB must provide a reason when they breach one of the validation checks. Where a data quality issue was identified, the reason provided is included in the table.
The smoking status is self-reported by the woman and therefore may be susceptible to “satisficing” where the woman is tempted to give an answer which is more socially acceptable, i.e. to say she is a non-smoker. Also, the definition does not distinguish between heavy and light smokers or how recently the woman smoked.
DQ Table 2 of the Excel data tables is provided annually in the quarter 4 report and shows the percentage of women whose smoking status was not known at time of delivery, for each quarter of the financial year, by Sub Integrated Care Board Location (Sub-ICB). Sub-ICBs with 5% or higher of maternities with an unknown smoking status are highlighted. Data quality comments (as provided by Sub-ICB) for previous quarters can be found in DQ table 1 of the relevant quarterly report.
SATOD v2
Data submitted for births occurring in July, August and September 2024 have been used for this measure with smoking statuses recorded +/- 3 days from the labour onset date. Where any births are towards the end of September 2024, then provisional data for October 2024 has been used to determine a smoking status. An impact assessment has been conducted which shows this has a negligible impact on the estimates.
Validation takes place at the point of entry. Further details on the validations carried out can be found in Appendix B.
Where any records from Trusts do not pass certain data quality criteria, then they are removed from the calculation of this metric. This helps explain why the number of maternities reported for SATOD v2 are lower than SATOD v1.
A list of these Trusts with any data excluded are provided in the Data Quality section. A list of the Sub ICB and LAs this affects are provided in SATOD v2 DQ Table 3 (Sub-ICB) and SATOD v2 DQ Table 4 (LA) of the Excel data tables.
Timeliness and punctuality
Timeliness refers to the time gap between publication and the reference period. Punctuality refers to the gap between planned and actual publication dates.
Publication has usually occurred around 8 to 10 weeks after the end of the reporting period. This has now been slightly delayed with the introduction of MSDS as a comparative data source adding up to another couple of weeks.
Accessibility and clarity
Accessibility is the ease with which users are able to access the data, also reflecting the format in which the data are available and the availability of supporting information. Clarity refers to the quality and sufficiency of the metadata, illustrations and accompanying advice.
All reports are accessible on the NHS England (previously NHS Digital) website. Data tables are provided in Excel format and as csv files, as part of the government’s requirement to make public data public.
NHS England has produced these reports since Quarter 3 2011-12. Prior to this the Department of Health and Social Care (DHSC) produced these reports, which are available at the links below:
Coherence and comparability
Coherence is the degree to which data which have been derived from different sources or methods but refer to the same topic are similar. Comparability is the degree to which data can be compared over time and domain.
Maternity Services Dataset as a replacement data source
This report presents statistics on women’s smoking status at time of delivery, at Sub Integrated Care Board (Sub-ICB), Integrated Care Board (ICB), regional and national levels. This release includes provisional data for quarter 2 of 2024-25 using data from the Smoking at Time of Delivery data collection which is submitted by commissioners (presented as SATOD v1). Alongside this and for the second time, comparative data using the Maternity Services Dataset is also presented using data submitted by Trusts (presented as SATOD v2) as a time series from quarter 1 of 2022-23 to quarter 2 of 2024-25. This is available for the same geographical breakdowns and includes an additional breakdown for Local Authorities. This will be repeated for subsequent quarters in 2024-25 to see how the estimates from both data sources align with a view to retiring the Smoking at Time of Delivery data collection at the end of this financial year. Until then, SATOD v1 remains the primary data source for this publication.
The time series estimates from both sources are in very close proximity indicating that MSDS is a good replacement as the data source for this publication. Please see chart on the 'Women known to be smokers at the time of delivery' page.
Other sources
The data in this report supplements the Adult Smoking Habits in the UK report which provides information on smoking rates, average number of cigarettes smoked and smoking during pregnancy at a national level. This continues the series of releases on smoking; previously provided by the General Household Survey (GHS) and the General Lifestyle Survey (GLF).
Previous organisational structures
On 1 April 2013, responsibility for commissioning services for women’s smoking status at the time of delivery moved from Primary Care Trusts (PCTs) to CCGs.
Changes to CCG and regional structure from 1st April 2021
On 1 April 2021, 38 CCGs are merged to create 9 new CCGs. Full details can be found at the link below:
April 2021 CCG organisational re-structure
Changes to ICB and regional structure from 1st July 2022
On 1 July 2022, Integrated Care Boards (ICBs) were introduced as part of Integrated Care Systems (ICSs) Implementation. Further details can be found at the link below:
Change in definition for calculating the proportion of women smoking at time of delivery
From April 2017, the methodology used to calculate the proportion of women smoking at the time of delivery changed in SATOD v1 to exclude women with an unknown smoking status from the denominator. Previously the percentage of unknowns may have resulted in the under reporting of the percentages for known smokers and non-smokers as they were effectively treated as non-smokers in the calculation. Information on these changes can be found in section C of the appendices. National time series data in table 1 was updated for all years to reflect the new methodology and is therefore comparable.
Trade-offs between output quality components
This dimension describes the extent to which different aspects of quality are balanced against each other.
The smoking status is self-reported by the woman and therefore may be susceptible to “satisficing” where the woman is tempted to give an answer which is more socially acceptable, i.e. to say she is a non-smoker.
Additionally, the definition does not distinguish between heavy and light smokers, or how recently the woman smoked.
Assessment of user needs and perceptions
This dimension covers the processes for finding out about users and uses and their views on the statistical products.
This publication is considered to be of particular interest to English NHS commissioning organisations. However, data and findings are also likely to be of interest to a broader base of users.
A consultation took place in 2016 across all NHS England (previously NHS Digital) statistical outputs which included this report.
Earlier this year, a proposal for the data source for this publication to be changed to the Maternity Services Dataset was included in a wider consultation: Health and social care statistical outputs published by DHSC (including OHID), NHSBSA, UKHSA, ONS and NHS England.
NHS England is keen to gain a better understanding of the users of this publication and of their needs. We also welcome any feedback on switching the data source for this publication in 2025/26 to the Maternity Services dataset. This may be sent to: [email protected].
Performance, cost and respondent burden
This dimension describes the effectiveness, efficiency and economy of the statistical output.
The cost incurred by data providers to collect and submit the Smoking at Time of Delivery Data was last estimated in 2013 at £148,000. The cost of collecting, processing and publishing the data centrally is estimated to be £35,000 per annum.
Confidentiality, transparency and security
The procedures and policy used to ensure sound confidentiality, security and transparent practices.
These publications are subject to an internal risk assessment prior to issue.
Information is disseminated at a high level of aggregation and the only small numbers that occur do not require suppressing as they are not considered identifiable or disclosive.
The data contained in this publication are Official Statistics. The Code of Practice for statistics is adhered to from collecting the data to publishing.
Please see links below to our latest relevant policies, these will be replaced with new combined NHS England policies in time:
Freedom of Information Process
Last edited: 19 December 2024 9:31 am