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Publication, Part of

Mental Capacity Act 2005, Deprivation of Liberty Safeguards England, 2019-20

Official statistics

Data Quality Statement


This data quality statement will provide users with an evidence-based assessment of the quality of the data used in the Deprivation of Liberty Safeguards official statistics, reporting against the nine European Statistical System (ESS) quality dimensions and principles appropriate to this output.

In doing so, this meets our obligation to comply with the  UK Statistics Authority (UKSA) Code of Practice for Official Statistics, particularly Principle Q3.1 which states that ”Statistics should be produced to a level of quality that meets users’ needs. The strengths and limitations of the statistics and data should be considered in relation to different uses, and clearly explained alongside the statistics.”


The degree to which a statistical product meets user needs in terms of content and coverage

The purpose of the DoLS collection and report is to inform the public and provide information which can help stakeholders make decisions about practice and policy. Information in this report will be of interest to organisations monitoring DoLS applications in England, such as the Department of Health and Social Care, the Care Quality Commission, local authorities, hospitals and care homes. It may also be useful to mental health charities, individuals being deprived of their liberty and their families who are interested in more information about DoLS and the extent of its use.

Accuracy and reliability

The difference between an estimated value and the true value

As part of the data collection process NHS Digital release a spreadsheet-based validation tool through which local authorities can run their annual data to check the accuracy of individual records. Use of this tool is not mandatory but many local authorities choose to use it to identify errors before making their submissions. There is no limit to the numbers of submissions that local authorities can make.

NHS Digital process all submissions following the mandated submission deadline and produce an automated data quality summary report for each submitting local authority. The data quality summary report examines variance in volume of activity in comparison to previous year volumes and the completeness and validity of the data submitted. It includes a number of data integrity validations, such as dates of sequential processes and identification of missing data. There is also the facility for submitters to record observations and explanations regarding their data. This leads to clarification being sought and double checking carried out by local authority officials, where figures are deemed to be outliers; potential errors and misunderstandings are known to have been eliminated.

Local authorities then have an opportunity to amend and resubmit their data and add any supporting commentary if they wished to before the second and final deadline.  Senior sign-off is required before local authorities can make their final submission to indicate the data has been subject to full quality assurance. 

NHS Digital works with local authorities in a bespoke way each year to resolve any residual issues, to ensure that the data submitted reflected as accurate a picture of DoLS activity in the year as possible. In some instances, this is not possible before the final data submission deadline; any data issues that were unresolved are noted in the data quality key information. Typical risks to data quality at local level which we would note arise when there is a change in underlying systems or personnel.

The finalised data were subject to the same data quality analysis and the results are shown in data tables of this publication. It is hoped that this analysis will provide users of the report with a clearer sense of the quality controls applied to the underlying data at a national, regional and individual local authority level. NHS Digital also has a suite of ‘behind the scenes’ internal processes built in order to manage risk to data quality for example automated and tested processed to compile the national level data from local data submitted by providers; checking procedures; various levels of approval and sign-off built in to the publication system.

There is a hierarchical governance structure overseeing the data collection: a DoLS Working Group investigates data quality issues and advise on how to manage these. This in turn reports to the Data Delivery Action Group, and then to the Data and Outcomes Board for senior stakeholder approval.


The DoLS data collection has received submissions from all local authorities in England in all years except 2016-17. Some comparisons to 2016-17 will be skewed or not possible for Northamptonshire and the East Midlands region due to non-submission of detailed data by Northamptonshire in that year. They did provide some high level data in order that some like-for-like comparison can be made across the two years at a national level. Users should exercise caution when comparing data between years for England and the East Midlands region.

Timeliness and punctuality

Timeliness describes the time between the date of publication and the date to which the data refer. Punctuality describes the time between the actual publication and the planned publication of a statistic.

This report contains data for the financial year covering the period 1 April to 31 March. The publication is released several months after the final submission deadline when local authorities provide the data to NHS Digital, following data processing, analysis and validation.

Due to the impact of Covid-19 and resourcing pressure at local authorities, the collection date was pushed back to allow local authorities to have more time to complete the data return. As a result, the publication date also had to be moved back from the original plans, however it is still published earlier than the 2018-19 publication due to improvements in the production process.

The release is in line with updated pre-announced publication dates.

Accessibility and clarity

Accessibility describes the ease with which users can access data.

This publication is available from the NHS Digital website and consists of data tables (including statistics by local authority) in Microsoft Excel format, reference documents in html format and a web-based Power BI comparator tool.

Reuse of our data is subject to conditions outlined here:

Clarity describes the quality and sufficiency of metadata, illustrations and accompanying advice.

A list of the data items collected together with their definitions can be found in the guidance notes for the data collection at:

The documents under the DoLS sections of the list can be used to identify what data have been collected from local authorities and to understand the terminology used within the DoLS reporting products.

We have also recently introduced a Data Dictionary for all Adult Social Care data collections, to improve the quality and coherence of metadata used by the data providers. This is in a beta phase currently and feedback is welcomed:

Background information and context around DoLS legislation and the data collection is also presented as part of the publication.

Coherence and comparability

Coherence is the degree to which data derived from different sources or methods, but that refers to the same topic, is similar

There are no other nationally published sources of data on DoLS activity with which these data could be compared.

Data is sourced from each local authority in England and compiled at national level by NHS Digital. There is no standard system used to record DoLS within local authorities and there are gaps in our understanding as to how this impacts on coherence and comparability. However, the metadata defined by NHS Digital and used by local authorities to extract the data from their systems and provide to NHS Digital is well defined and accessible to all. A DoLS Working Group, including those who use local administrative systems in their data to day work, exists to provide advice and clarification to NHS Digital on such matters. 

Comparability is the degree to which data can be compared over time and domain, for example, geographic level

In previous collection periods, DoLS applications were processed by both local authorities and Primary Care Trusts (PCTs) and NHS Digital collected data from both organisation types. Data were submitted in aggregate form and collected on a quarterly basis. From 2013-14 onwards, all applications from both health and care settings have been processed by local authorities and the returns are submitted at a case level on a yearly basis. The DoLS collection has remained mandatory for all local authorities.

The 19 March 2014 Supreme Court judgment in the case of Cheshire West widened the number of individuals who may be considered to be deprived of their liberty and hence require an application in respect of DoLS. This resulted in a ten-fold increase in the number of DoLS applications from 2014-15 onwards. While the analysis methodology has remained the same, this considerable increase in volumes will need to be acknowledged when analysing data over this period.

Trade-offs between output quality components

Trade-offs are the extent to which different aspects of quality are balanced against each other

In order to balance aspects of data quality two data submission periods are made available for local authorities. Data Quality reports and support were made available to those local authorities who submitted by the first deadline, in order to give data providers the opportunity to address any issues found. Local authorities were able to make updates to their data during this validation period. After the second submission period the dataset is then finalised. Any issues remaining are noted in the data quality information published, but no attempt is made to amend the data.

Assessment of user needs and perceptions

The processes for finding out about users and uses, and their views on the statistical products

The collection methodology for the 2013-14 and subsequent DoLS collections was changed following a “zero-based review” of adult social care data collections. The key changes introduced were to move to collecting the data annually and at a case level, rather than quarterly and in aggregate. The 2013-14 DoLS collection was developed following consideration of this feedback and was approved by the Department of Health (DH), the Department of Communities and Local Government (DCLG) and other key stakeholder organisations including the Association of the Directors of Adult Social Services (ADASS).

A Working Group exists with the aim to manage the development of the DoLS data collection to reflect the requirements of users and policy. The group includes representatives from NHS Digital, Department of Health and Social Care, Care Quality Commission and local authorities.

Changes to upcoming collections can be seen in the most recent September letter and the Data Provision Notice

Following closure of the data submission window, data providers had the opportunity to complete an online user survey to provide feedback on all Adult Social Care data collections and reporting processes hosted by NHS Digital for 2018-19

We are always interested in knowing if the DoLS data collection is meeting your needs and, if not, what improvements we could make for the future. If you would like to make any comments, please contact us by:


Telephone Enquiries: 0300 303 5678

Performance, cost and respondent burden

The DoLS collection is mandated for all local authorities. The data collection process used in this publication is subject to assurance by the Data Coordination Board. This is to ensure that data collections do not duplicate other collections, minimise the cost to all parties and have a specific use for the data collected.

The burden of the DoLS collection has been assessed and approved, the burden of any changes to the collection are similarly assessed, to ensure that they do not create undue burden for local authorities.

In 2019-20 a decision was made, in accordance with the governance boards for DoLS to remove three data items from the collection in order to minimise the burden for providers in completing data items that were not used due to data quality issues.


We regularly survey and seek feedback from those submitting the data in order to identify efficiencies and improvements that we can introduce to help local authorities. For example in 2019-20 we amended the data submission system to allow more than one local authority colleague to hold a system login, and in turn this reduced the burden on one person and ensured a better submission process for the data providers.

Confidentiality, transparency and security

All statistics are subject to a standard NHS Digital risk assessment prior to issue. The risk assessment considers the sensitivity of the data and whether any of the reporting products may disclose information about specific individuals. Methods of disclosure control are discussed and the most appropriate methods implemented. As a result of this process, all statistics associated with this data collection have been rounded to the nearest multiple of five, and values less than five have been suppressed in tables where necessary. Percentages are rounded to the nearest 0.1 per cent.

NHS Digital aims to be transparent in all its activities. A description of the collection process and any issues with the quality of the DoLS data are documented in this publication.

DoLS data are submitted to NHS Digital through a secure electronic file transfer system called SDCS. The submitted files are transferred from SDCS and stored on a secure network with restricted access folders. Only a limited number of analysts are granted access to the DoLS folders.

Please see links below for more information about related NHS Digital policies:

Statistical Governance Policy:

Freedom of Information Process:

Data Access Request Service:

Privacy and data protection:

Last edited: 7 June 2021 10:08 am