General MSDS guidance

Slide 1

Welcome to this short video demonstration on derived fields from the Maternity Services Dataset. This video is part of a series of videos to help you understand measures built from the Maternity Services Dataset (referred to as MSDS).

Slide 2

Today we will look at the definition of a derived field and how they are used in the maternity services dataset (MSDS). We will then look at an example of how a derived field is used to build a measure in the monthly statistics publication.

Slide 3

A list of derived fields used to build MSDS metrics and their descriptions can be found in the ‘Derivations’ tab in the MSDS metadata.

The technical output specification should be used in conjunction with the metadata, and contains further derived fields and information  in MSDS. A derived field is specified as “D” under the “Group Mandation” column. 

There is also a video on Understanding the Data: Metadata file available on the MSDS guidance hub (link above).

Slide 4

For the purpose of this video, we will be referring to the Maternity Services Dataset (MSDS). Derived fields are calculated from 1 or more existing fields in the dataset, from 1 or more dataset tables. They do not already exist in the dataset. These fields are not submitted by data providers, they are created after the data is submitted.

Slide 5

Derived fields in MSDS are used to build measures reported on in monthly and annual statistics publications. Some examples of derived fields in MSDS include: GestAgeBooking (The gestational age at booking), AgeAtBirthMother (Mother’s age in years when baby is born), BirthsPerLabandDel (The number of births associated with this labour and delivery). Some examples of how derived fields are used to build MSDS metrics will be covered later in this video.

Slide 6

Understanding and identifying constructions can help improve data quality. This can help data submitters to identify the underlying fields that may require improvement in monthly data submissions. An advantage of derived fields is they ensure consistency in the way a value is calculated (e.g. a date).

For queries on maternity data quality, please contact maternity DQ: [email protected]

Slide 7

In the next section, we will look at examples of derived fields in MSDS in further detail. We will also look at an example of how a derived field is used to build a metric.

Slide 8

We will now look at an example of the derived field ‘AgeAtBirthMother’ in MSDS in further detail. This field appears in Table MSD401 Baby Demographics, and the definition is ‘Mother’s age in years when baby is born’. This field uses Person Birth Date (Mother) from Table MSD001 and Person Birth Date (Baby) from Table MSD401. Both of these fields are mandatory for providers to submit.  It is calculated by subtracting the Person Birth Date of the mother from the Person Birth Date of the baby. The difference is calculated in years. An example would be the difference in years between 1 October 2000 and 1 September 1965 is 35. Therefore, the Mother’s age in years when baby was born is 35 years.

Slide 9

Another example of a derived field is ‘BirthsPerLabandDel’. This field appears in Table MSD301 Labour and Delivery, and the definition is ‘The number of births associated with this Labour and Delivery’. This field is calculated by looking at the Labour and Delivery Identifier in Table MSD401 Baby Demographics and counting the number of records that match the Labour and Delivery Identifier in Table MSD301. This field is useful for building metrics that only look at singleton births.

Slide 10

We will now look at how the derived field “Births Per Labour and Delivery” is used to build one of the Clinical Quality Improvement Metrics from MSDS. The metric CQIMDQ29 is defined as “The percentage of babies (singleton) born that have a valid delivery method recorded in the current reporting period”. The derived field BirthsPerLabandDel is set to 1 in building this metric, to ensure only singleton births are included in this measure.

Slide 11

To calculate metric CQIMDQ29, we need to build a numerator and a denominator. The metric is “The percentage of babies (singleton) born that have a valid delivery method recorded in the current reporting period”. For the denominator, we look at a count of babies born within the reporting period, where births per labour and delivery is equal to 1. For the numerator, we take the cohort of babies in the denominator and retain only those where the delivery method is known. A full description of how this measure is built can be found in the metadata file, in the CQIMDQ Measures Construction tab.

Slide 12

This is another example of how a derived field is used in the maternity services monthly publication. GestAgeBooking is used to produce a bar chart showing the gestational age of the baby at the booking appointment. The National Institute for Health and Care Excellence (NICE) recommends that this appointment should ideally take place before 10 weeks' gestation. This measure is also available in the maternity services dashboard and allows the user to compare data from different providers in England. The derivation, GestAgeBooking is also used as part of the build for more complex measures, such as the Continuity of Carer measures.

Slide 13

This is a short demonstration on using the maternity services dashboard to look at the measure gestational age at booking, based on the GestAgeBooking derivation. Click “Open the dashboard”. Select Org Profile. Select the indicator you wish to view. Here we will choose Gestational age at booking. This displays the data alongside the national figure for England, displayed by these yellow rectangles. We can also change the trust we want to look at. We can also change the month of data we want to view. We can also change the category of the indicator to view the categories in more depth. This chart shows a time series of gestational age at booking for this trust. This chart shows a comparison for this measure for all trusts.

Slide 14

In this video, we have looked at the purpose of derived fields and the benefits of using them. We have also looked at how they are calculated in the Maternity Services Dataset, and examples of how they are used to build metrics.

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This brings us to the end of the video.

Thank you for watching this video demonstration on derived fields in the Maternity Services Dataset.

We value your feedback, please use the email address here if you wish to get in touch.

Thank you

Slide 1

Welcome to this short video demonstration on how to use the Maternity Services Dataset Metadata file.

This video is part of a series of videos to help you understand measures built from the Maternity Services Dataset referred to as MSDS.

Slide 2

Today we will look at the Metadata file which describes the measures published in the Maternity Services Monthly Statistics and explains how they are built.

Please note, the metadata file is continually reviewed and improved. This information is correct as of June 2022.

Slide 3

The Metadata file is located within the Maternity Services Guidance hub. This can be found by following the top link here.

In each published month of the Maternity Services Monthly Statistics, there is also a link to the Metadata file under the Resources section. The monthly statistics are available from the bottom link here.

This video also refers to the Maternity Services Technical Output Specification file when identifying derived fields. It is available here.

Slide 4

In the next section we will discuss the structure of the metadata file. First, we will navigate through the file then discuss the metadata tabs’ contents.

Slide 5

After downloading and opening the metadata file from the guidance hub, your file will open on the cover page. It is recommended to download a new version of the file with each publication month, as there may be new additions or alterations. The latest version can be found on the Maternity Guidance hub. All the tabs that can be found in the document are listed on the cover page.

Updates and amendments to the file can be found on the version control tab, with the details of the latest version listed at the bottom.

Going through the remaining tabs, you may notice each tab layout is visually different. However, all measure tabs include the methodology or logic of each of the measures listed.

Reference numbers and measure names are also included in each tab. These can be cross-referenced with the published data, either in the monthly data csv, measures csv or the Power BI dashboard. The Clinical Quality Improvement Metrics , also referred to as CQIM, Footnotes tab includes additional details that will aid the understanding of the construction of CQIM rates and DQ measures.

Finally, there is a glossary of acronyms used within the metadata file.

Slide 6

The first tab of the metadata file, the cover page, contains details of the data included in the Maternity Services Monthly Statistics. This includes the Monthly Data and Measures files.

The MSDS Data Quality report is also described on this page. It is available monthly alongside the Maternity Services Statistics under the Resources section. It is available here.

Lastly, there are also links to useful resources including the Data Dictionary, as well as further Contact Information.

Slide 7

The Monthly Data Measures tab provides descriptions and constructions for the measures included in the Monthly Data file.

This is published as “Data csv” in the maternity services monthly publications.

Slide 8

Now we will look at the tabs that cover the constructions found in the monthly measures csv in the maternity statistics publication.

Each indicator family is separated into different tabs.

Some indicator families have associated data quality measure criteria that providers must meet to be included in the rates.

Indicator Families with data quality criteria are separated further into Rate and Data Quality (DQ) tabs in the Metadata file.

Slide 9

These are some examples of indicator families that can be found in the metadata file.

The Clinical Quality Improvement Metrics, referred to as CQIMs. There is a tab which covers Rates Construction and a tab to cover data quality Measures Construction. There is a series of guidance videos for CQIM rates available on the guidance hub.

;The Continuity of Carer Rates Construction and Continuity of Carer data quality Measures Construction. There is also a series of guidance videos for Continuity of Carer measures available on the guidance hub.

;Saving Babies Lives Measures Construction

And Other Rates Construction and Other DQ Metrics Construction, which includes indicator families such as Birth and BMI_by_14weeks that do not sit under the policies covered by the above indicator families.

Slide 10

The derivations tab includes a list of derivations that NHS Digital produces to create more efficient data.

Derived fields are not submitted by data providers. They are calculated from 1 or more existing fields in the dataset, from 1 or more dataset tables.

We can see that the derivations tab includes a description of each derivation, the table it is in, its name, number, and data type, as well as the field(s) it is based on and how the derivation is formed (rule).

The tables, derivation numbers and names can also be found in the Technical Output Specification, as well as the derivation descriptions and rules.

There is also a video on Derived fields available on the MSDS guidance hub, available here.

Slide 11

In the next section, we will talk about identifying derivations in the measure constructions and the benefits of understanding them.

Slide 12

Understanding and identifying derived fields used in the construction of NHS Digital measures can help you identify which underlying fields may require improvement in your monthly data submissions.

For specific assistance with maternity data quality, please contact the Maternity data quality team.

Slide 13

All fields described in the construction of a measure include the table that the field is found in.

Use the metadata file in conjunction with the Technical Output Specification (TOS). Search for the field name in the specified table.

Derived fields are presented in the table below the fields that are submitted by a trust, and the cells are highlighted in grey.

A derived field is also specified as “D” under the Group Mandation column.

Slide 14

In table MSD101 pregnancy and booking details, the unshaded cells show fields that you would expect to fill in for submission. These are either mandatory fields or information you should submit if you hold the information, called required fields. These fields are labelled M or R in the Group Mandation column.

As we scroll down further, notice the grey cells below. Here, the Group Mandation is the letter D, telling us that the field is a derivation. The method or logic for each derivation is included in column P, and describes which of the submitted fields underlie the derivation.

Slide 15

This brings us to the end of the video.

Thank you for watching this video demonstration on how to use and navigate the Maternity Services Dataset Metadata.

We value your feedback, please use the email address here if you wish to get in touch.

Thank you