Accuracy is the proximity between an estimate and the unknown true value.
Reliability is the closeness of early estimates to subsequent estimated values.
The MSDS is a rich, person level data set that records packages of care received by individuals in contact with NHS-funded maternity services. NHS Digital provides a number of different reports at different stages in the data flow to ensure that the submitted data reflects the services that have been provided:
For data suppliers only:
At the point of submission:
- Providers receive immediate feedback on the quality of their submission through a validation file. This file includes record-level reports of any submission errors, giving the data providers detailed information about which records produced which errors.
On receipt of processed data by NHS Digital:
- A variety of data quality checks are run as part of the validation and load process for monthly data, prior to production of this monthly release. Where there are concerns about data quality we contact providers directly so that any issues with local data extraction processes can be addressed for a future submission.
For all users:
As part of this publication, we publish a CSV file of data quality of submissions from maternity service providers.
Users of the data must make their own assessment of the quality of the data for a particular purpose, drawing on these resources.
In addition, local knowledge, or other comparative data sources, may be required to distinguish changes in volume between reporting periods that reflect changes in service delivery from those that are an artefact of changes in data quality.
The analysis in this report is based on the latest data submitted by providers during the two month window to provide data. Any data which are re-submitted by a provider during the submission window will be used in place of an earlier submission within the window. We invite and welcome feedback from users on our constructions.
Coverage – are all eligible providers submitting data?
All providers of NHS-funded maternity services should submit MSDS data. However, at present not all providers are making submissions.
All trusts made a submission, one independent provider did not. However some trusts submitted a limited number of tables.
This publication reports on activity that was submitted for the September 2020 reporting period. As a dramatically revised national level data set there are a number of issues in terms of non-response from providers which in turn has an impact on the geographical coverage expected of the data set, hence caution should be taken when interpreting the data at levels higher than individual provider level.
Because of this, no figures derived from the MSDS data have been presented as England total figures, rather they are presented in terms of all providers who submitted data to the MSDS for the reporting period in question. While the number of submitting providers is all we expect, the number of providers submitting valid data for each data table and data item varies widely. Totals therefore continue to be presented as 'all submitters' values, and users of the data should consider the coverage for the relevant analysis when interpreting the data.
Coverage – is data for all eligible people included in the submission?
Local knowledge may be required to assess the completeness of a submission, based on information about local caseload. This publication provides detailed information about activity and providers and commissioners are encouraged to review this to ensure that submissions accurately reflect the local situation. Providers should also use all the aggregate record counts produced at the point of submission as part of the Data Summary Reports to check coverage in key areas (e.g. number of booking appointments.)
Where an organisation is submitting delivery data to MSDS, the number of births reported in a month can be compared to the 2018-19 monthly average number of births in HES to review the levels of activity reported in the MSDS for each organisation (noting that MSDS is not limited to births in hospital). Where an organisation is not yet submitting delivery data to MSDS, a similar comparison can be made using the number of booking appointments in the month, bearing in mind that not all booking appointments will lead to a birth for that pregnancy within a reporting organisation.
Validations are in place to ensure that there is only one booking appointment for each woman submitted to NHS Digital per organisation for the particular reporting period. It is possible that one woman may have multiple booking appointments recorded for the same pregnancy for different providers. For any calculated total value presented in this report a woman is only counted once in relation to the activity related to the booking appointment. For example, if a woman is reported for a booking appointment by two separate organisations within the same NHS England Region then they would be counted in any total for each of these providers presented at the provider level but would only be counted once for the overall NHS England Region. However, if the woman was reported by two separate providers within two separate NHS England Regions then they would be counted in the overall total calculated for each NHS England Region.
If a woman is reported for a booking appointment by two separate organisations within the same NHS England Region and different data are submitted by each provider then this woman may be counted twice for the overall NHS England Region total. For example, where a woman has an age recorded as 39 by one provider and 40 by another provider this woman would be counted in the NHS England Region total twice, once in the '35 to 39' age group and once in the '40 to 44' age group.
Similarly, a baby reported by two separate organisations within the same NHS England Region with an Apgar score at 5 minutes of 6 recorded by one provider and 8 by another provider would be counted in the NHS England Region total twice, once in the '0 to 6' group and once in the '7 to 10' group.
Timeliness of recording events on local systems
Whilst local systems may be continuously updated, the MSDS submission process provides a time-limited opportunity for data relevant to each month to be submitted. The submission window opens the day after the reporting month and remains open for two months. This means that the timeliness of recording all relevant activity on local systems has an impact on the completeness of the MSDS submission. For example, a booking appointment made in May 2020, but not entered onto the local system until August 2020, will not be included in the May 2020 submission (deadline end of July 2020). Providers should use the data summary reports produced at the point of submission to ensure that all relevant data has been included.
The submission requirements for MSDS are that all appropriate activity (e.g. booking appointment, dating scans, etc.) be included in the submission for each month in which they start, continue or end. It is important that data providers ensure that NHS numbers are submitted consistently because this is a key piece of information for creating the person identifiers in our records.
Quality of experimental analysis
It should be noted that these statistics are presently experimental in nature and are likely to be subject to further refinement; reference should be made to all accompanying footnotes and commentary when using these statistics.