Official Statistics

Background Quality Report: UK service personnel amputation statistics

Published 27 July 2023

1. Contact details

The Deputy Head of Defence Statistics Health is responsible for these statistics. The contact details are:

E-mail: Analysis-Health-PQ-FOI@mod.gov.uk

Website: Statistics at MOD on GOV.UK.

Defence Statistics Health
Ministry of Defence
Oak 0 West
Abbey Wood North
Bristol
BS34 8JH

2. Introduction & Statistical Presentation

This annual report provides statistical information on the number of UK service personnel who suffered an amputation for the latest five-year period 1 April 2018 to 31 March 2023. An amputation is the traumatic (accidental) or surgical removal of part of the body and can range from the loss of entire limbs to the loss of part of a finger or toe. The number of “significant multiple amputees”, comprising of the loss of more than one limb, and the number of UK service personnel with an amputation who have been medically discharged have been provided.

Information on the number of UK service personnel who suffered a traumatic or surgical amputation resulting from injuries sustained in Afghanistan and Iraq has also been provided, for the period 7 October 2001 to 31 March 2023.

The amputation statistic was first published in February 2010, providing statistical information on the number of UK service personnel who, as a result of an injury sustained whilst deployed in Iraq or Afghanistan, have suffered a traumatic or surgical amputation. This ranges from the loss of part of a finger or toe up to the loss of entire limbs. In addition, the numbers of “significant multiple amputees” are provided on an annual basis, as are the number of surviving amputees that have been medically discharged. Defence Statistics also incorporated an annex to include the number of UK service personnel that had an amputation as a result of injuries or illness sustained in locations that were not Afghanistan or Iraq, to give a broader picture of amputees within the UK armed forces.

Defence Statistics Health opened a consultation with internal and external stakeholders on 27 July 2017, regarding the proposed cessation of this publication. There were two negative responses during the consultation period objecting to the cessation of the report. As a result of these objections the decision was made to continue to publish the amputation statistics on an annual basis in a revised format. The focus of the report is now on all amputations in the UK armed forces during the past five years, with sub-sections on amputations that have occurred as a result of injuries sustained in Afghanistan and Iraq for the overall period. The report was previously presented by financial year and quarter, the revised report is presented by financial year only.

Since 2001, the Royal Centre for Defence Medicine (RCDM), based at the University Hospital Birmingham Foundation Trust (UHBFT), has been the main receiving unit for military casualties evacuated from an operational theatre. In the Birmingham area, military patients can benefit from the concentration of five specialist hospitals (including Queen Elizabeth) to receive the appropriate treatment. Queen Elizabeth is at the leading edge in the medical care of the most common types of injuries (e.g. polytrauma) our casualties sustain, and most casualties will be treated there, but others may be transferred to another hospital (in Birmingham or elsewhere) if that is where the best medical care can be given.

Military patients will require further rehabilitation care following initial hospital treatment, in most cases they are referred to the Defence Medical Rehabilitation Centre (DMRC), which provides advanced rehabilitation and includes inpatient facilities. The prosthetics department is also located at the DMRC, fitting limbs to amputee patients.

2.1 Operations in Afghanistan

Operation VERITAS is the name for UK operations in Afghanistan which started in October 2001 and ended in March 2006. The UK was involved in Afghanistan alongside Coalition forces, led by the US under Operation Enduring Freedom (OEF), from the first attacks in October 2001.

Operation HERRICK is the name for UK operations in Afghanistan which started 1 April 2006 and ended on 30 November 2014. UK forces were deployed to Afghanistan in support of the UN authorised, NATO led International Security Assistance Force (ISAF) mission.

Operation TORAL which started 1 December 2014 and ended August 2021, was the UK’s post 2014 contribution to operations in Afghanistan under the NATO RESOLUTE SUPPORT MISSION.

Operation PITTING: was the evacuation of British Nationals and former British staff eligible for relocation under the Afghan Relocation and Assistance Policy from 13 to 29 August 2021.

2.2 Operations in Iraq

Operation TELIC is the name for UK operations in Iraq which started in March 2003. There was a drawdown of troops in July 2009 and Operation TELIC closed on 21 May 2011. UK forces were deployed to Iraq to support the government’s objective to remove the threat that Saddam posed to his neighbours and his people and, based on the evidence available at the time, disarm him of his weapons of mass destruction. The government also undertook to support the Iraqi people in their desire for peace, prosperity, freedom, and good government.

Operation SHADER Started 6 August 2014. The MOD is providing military support to the US led coalition to defeat Daesh in Iraq and Syria. This support includes training Kurdish forces with over 320 tonnes of UK gifted weapons, UK gifted machine guns, ammunition, and other military equipment. Since the parliamentary vote, the RAF has flown successful strikes and provided valuable intelligence and surveillance. Further information on Op SHADER can be found on GOV.UK.

3. Statistical Processing

The annual statistic includes:

• Counts of the number of surviving amputees from all locations, by financial year for the past five years.
• Counts of the number of surviving amputees from Iraq and Afghanistan, by financial year for the overall time periods.
• Counts of significant multiple amputees from Iraq and Afghanistan, by financial year for the overall time periods.
• Counts of the number of surviving UK service personnel amputees that have been medically discharged by the principal ICD-10 cause code group for which they were medically discharged.

3.1 Source Data

The amputation data is compiled from ten separate sources.

UK service personnel who have sustained a partial or complete limb amputation as a result of injuries on Op VERITAS, Op HERRICK and Op TELIC prior 1 April 2006 have been identified from the dataset used to compile the following research paper: Dharm-datta, S; Etherington, J.; Mistlin A. & Clasper J, 2011, Outcome of amputees in relation to military service, Journal of Bone and Joint Surgery – British Volume, Vol 93-B, Issue SUPP_I, 52.

From 1 April 2006 onwards, the data is compiled from the nine sources detailed below.

Complex Trauma Database

The Complex Trauma database is managed by the Defence Medical Rehabilitation Centre, and commenced in June 2008 to record information on patients receiving in-patient care on the complex trauma ward.

Prosthetics Database

The Prosthetics database is managed by the Defence Medical Rehabilitation Centre, and commenced in June 2006 to record information on patients fitted with a prosthetic limb(s).

Defence Patient Tracking System

The Defence Patient Tracking System (DPTS) commenced on 8 October 2007. The DPTS was set up to enable the capture of tracking data for aeromedically evacuated patients at the place where healthcare is being delivered along the care pathway.

Joint Theatre Trauma Register

The Joint Theatre Trauma Register (JTTR) commenced during 2003 to improve the care of the seriously injured patient from the point of injury to the point of discharge from hospital treatment.

Defence Medical Information Capability Programme

Defence Medical Information Capability Programme (DMICP) has a centralised data warehouse of coded information. It is the source of electronic, integrated healthcare records for primary healthcare and some MOD specialist care providers. DMICP was rolled out in 2007 and legacy medical data for currently serving personnel was migrated across during rollout.

Medical data is stored in the DMICP data warehouse using read codes. The read codes that were used to search the DMICP data warehouse for military personnel with an amputation were: 7L04 to 7L08, 7L06 to 7L06z, 7L062, 7L063, 7L064, 7L08 to 7L08z, SyuA9, SyuA6, SyuBG, S9606, 14N4 to 14N4Z, 14N41, S95, S96, S97, S960 to S960A, U635, TB05, SP16, SC09, 8D47, DMSRC251, SC3C3, SC3D3, S906, SR4 (SR40 to SR44), SA7X, S970X, N36yM, 2G42 to 2G47, 2G4A, 2G4B, 2G56, 2G57, 2G61, 2G62, ZV6F0 to ZV6F8, SH25, SH45, SH35, SH55, SH65, SH95.

Please note that if information was entered as free text in the patient record, then it was not available in the DMICP data warehouse and would not be retrieved using the search for read codes. There has been no audit of the accuracy of the coded data entered into the patient record. DMICP is a live data source and is subject to change.

Health and Safety Database

MOD personnel report health and safety incidents using a variety of reporting mechanisms. Since 2005, armed forces personnel and civilians report incidents to Incident Notification Cells or via their on-site Safety, Health, Environment and Fire (SHEF) advisors. Defence Statistics Health then collate this data into a single Health and Safety dataset.

The data presented cover incidents which include any person whose injury was recorded on the below MOD health and safety systems:

• Army Safety Centre Incident Notification System (INS) as at 31 March 2023
• Accident and Incident Recording System (AIRS) as at 30 June 2020 (replaced by FSIMS)
• RAF Functional Safety Information Management System (FSIMS) as at 31 March 2023
• Defence Equipment and Support Cell (DINC) as at 31 March 2023
• Defence Infrastructure Organisation (DIO) as at 31 March 2023
• Head Office and Corporate Services (HOCS) as at 31 March 2023
• UK Strategic Command (StratCom, previously Joint Forces Command) as at 31 March 2023
• Navy Lessons and Incidents Management System (NLIMS) as at 31 March 2023

A search was carried out on all reported health and safety incidents using the following keywords: “amput”, “severed”, and “loss of limb”. Defence Statistics Health has visually validated and checked all search returns and excluded all duplicate records and any incidents that did not relate directly to amputations.

Health and Safety statistics are published on an annual basis.

Medical Discharges

This report presents the number of amputees who have been discharged from service on medical grounds as at 31 March 2023, regardless of the conditions for which they have been medically discharged.

Medical discharges are reported for regular service personnel only (including Gurkhas and Military Provost Guard (MPGS)) and excludes all reservist personnel. This is because the medical discharge process and medical record information for reservist personnel is not comparable to that of regular personnel. Most reserve personnel do not receive their primary medical care from MOD, but instead receive their primary medical care from the NHS. Therefore, Defence Statistics Health are unable to verify the quality of information relating to the discharge of reservist personnel and it has not been deemed appropriate to include information on this population until further understanding is gained.

Medical discharges are the result of a number of specialists (medical, occupational, psychological, personnel, etc.) coming to the conclusion that an individual is suffering from a medical condition that pre-empts their continued service in the armed forces. Statistics based on these discharges do not represent measures of true morbidity or pathology. At best they indicate a minimum burden of ill-health in the armed forces. Furthermore, the number and diversity of processes involved with administering a medical discharge introduce a series of time lags, as well as impact on the quality of data recorded.

Although medical boards recommend medical discharges, they do not attribute the principal condition leading to the board to the individual’s time in service. A medical board could take place many months or even years after an event or injury and it is not clinically possible in some cases to link an earlier injury to a later problem which may lead to a discharge.

Information was sourced from electronic personnel records (DMICP) and manually entered paper documents from medical boards (FMed 23’s). The primary purpose of these medical documents is to ensure the appropriate administration of each individual patient’s discharge. Statistical analysis and reporting is a secondary function.

Cause information extracted from FMed 23 forms, and as read codes from DMICP, were mapped, where possible, to the International Classification of Diseases and Related Health Problems version 10 (ICD-10). Causes are presented by ICD-10 chapter.

Medical discharge information was also used to identify personnel medically discharged with a principal or contributory cause of an amputation for inclusion in the overall figures. For this, the following ICD-10 codes were searched: S081, S088, S089, S281, S382, S383, S480, S481, S489, S580, S581, S589, S680, S681, S682, S683, S684, S688, S689, S780, S781, S789, S789, S880, S881, S889, S980, S981, S982, S983, S984, T050, T051, T052, T053, T054, T055, T056, T057, T058, T059, T096, T116, T136, T147, T870, T871, T872, T873, T874, T875, T876, Z890, Z891, Z892, Z893, Z894, Z8941, Z895, Z896, Z897, Z898, Z899, Z900, Z904, Z905 and Z907.

Medical discharges statistics are published on an annual basis.

Armed Forces Compensation Scheme

The Armed Forces Compensation Scheme (AFCS) is a no-fault scheme which provides compensation for injury, illness or death caused by service in the UK Armed Forces on or after 6 April 2005.

Figures provided were sourced from data stored on the Compensation and Pension System (CAPS). Claimed condition information is recorded on CAPS in a free-text field. To identify claims awarded for amputations, the ‘tariff description’ field for ‘amputation’ was searched.

Armed Forces Compensation Scheme statistics are published on an annual basis.

Directorate of Judicial Engagement Policy (DJEP)

The Common Law Claims & Policy Division (CLC&P) is responsible for processing common-law, non-contractual compensation claims against and on behalf of the Ministry of Defence (MOD) at home and abroad. Data is collated from several different sources: DJEP-CLCP’s Claims handling information payment system (CHIPS) is used for claims managed in-house. MOD’s contracted claims handlers Royal Sun Alliance (RSA), Gallagher Bassett– provide the information on the claims for which they are responsible. RSA provide information on claims prior to 30 April 2007; Gallagher Bassett on claims received from 1 May 2007.

MOD compensation claims statistics are published on an annual basis.

3.2 Definitions

A traumatic or surgical amputation can range from the loss of part of a finger (including fingertip) or toe up to the loss of entire limbs. This definition only includes personnel who survived their injuries.

A UK service person is defined as an amputee if they are recorded as having an amputation in the following data sources: Complex Trauma database, Prosthetics database, Defence Patient Tracking System, Joint Theatre Trauma Register, Armed Forces Compensation Scheme, Health and Safety, Defence Medical Information Capability Programme, Medical Discharges, and Directorate of Judicial Engagement Policy.

A UK service person is classified as a significant multiple amputee if they have had a limb amputation at or above the wrist or ankle on more than one limb (that is, they have lost at least two hands and/or feet). In the data this is determined from a number of fields including ais_description/surgical description, injury_notes, body region and body side. Multiple amputations may be described in one record or there will be 2 or more records containing information about different amputations.

3.3 Methodology

All data sources are cross-checked against each other and records that don’t appear in all datasets and any inconsistencies are manually reviewed and where feasible followed up to ensure that an individual is an amputee. Further validation steps are then taken to ensure a unique count of amputees is taken from the ten datasets and presented in the publication.

Most of the data sources contain a country, location or operation name field, these fields are used to determine whether a UK service person was injured in Afghanistan or Iraq.

Once the data is confirmed as being accurate, the tables can be populated. The figures released in previous publications are checked to see if they require revisions and numbers smaller than five are suppressed, to avoid providing disclosive information on individuals. If suppression is needed, previous publications are also checked to ensure numbers cannot be derived from totals and would therefore need to be revised.

3.4 Frequency of data collection

Data is provided from the relevant suppliers on an annual basis. It takes approximately three weeks to ensure all the data has been received, validated and the report produced. The annual publications are released at the end of July.

Planned publication dates can be found on the GOV.UK Official Statistics Release Calendar.

3.5 Data collection

All data sources are provided in a spreadsheet, anonymised, and stored in the amputations database.

3.6 Data validation

Validation routines on each of the datasets are carried out to check on the names and service numbers of casualties, to ensure the accuracy in counting UK military casualties and to check whether they’ve previously been included in the statistics.

4. Quality Management

4.1 Quality Assurance

The MOD’s quality management process for Official Statistics consists of three elements:

1. Regularly monitoring and assessing quality risk via an annual assessment.
2. Providing a mechanism for reporting and reviewing revisions/corrections to Official Statistics.
3. Ensuring BQRs are publishing alongside reports and are updated regularly.

5. Relevance

5.1 User Needs

Defence Statistics developed the amputation statistic in response to increased interest from the general public and ministers in the injuries sustained by UK service personnel on operations. The two main purposes of this report are:

1. To report on the impact of operations in Afghanistan and Iraq, with regards to amputations sustained by service personnel.
2. To inform the NHS and charities of the potential caseload involved in caring for amputees discharging from the UK armed forces who are eligible to access the veteran’s prosthetics and rehabilitation programme.

The MOD are committed to making information on operational casualties public but must draw a line between how much information is provided regularly in the public domain and information which compromise operational security of UK armed forces personnel or which risks breaching an individual’s right to medical confidentiality. This report is supporting the MOD’s commitment to release information wherever possible.

During 2009 the department had numerous requests for information regarding the number of UK service personnel who have sustained an amputation as a result of injuries in Iraq or Afghanistan; these included an e-petition request to 10 Downing Street and a question being raised in Prime Ministers Questions about whether the Prime Minister would release amputation numbers. The Prime Minister agreed that the stats would be produced annual and published on the internet.

The release is used to answer parliamentary questions and Freedom of Information requests. The report is also useful for internal customers in Surgeon General’s department as, for example, the statistics are used to inform policy and funding decisions in the Prosthetics department at the Defence Medical Rehabilitation Centre (DMRC).

The data presented include: all partial and complete traumatic or surgical amputations between 1 April 2018 and 31 March 2023; partial and complete traumatic or surgical amputations sustained as a result of injuries in Afghanistan between 7 October 2001 and 31 March 2023 and; partial and complete traumatic or surgical amputations sustained as a result of injuries in Iraq between 1 March 2003 and 31 March 2023.

This publication does not include UK service personnel who have had an amputation before their entry date or since leaving the armed forces. Defence Statistics consulted with a subject matter expert in the complex trauma team at the Defence Medical Rehabilitation Centre, to gauge how many personnel have had an amputation that is attributable to their service after leaving the armed forces. They advised that service personnel are unlikely to have amputations performed after they leave service unless involved in further trauma (for example, motorbike accidents/collisions) or for older personnel, disease-related conditions such as peripheral vascular disease or diabetes.

This report is currently limited in terms of the amount of information it can include, specifically in relation to the type of amputations seen (e.g. lower limb/upper limb). It would increase the risk of an individual being identified and compromise their right to medical confidentiality. In addition, there is a risk of compromising operational security by providing information that could be used by the enemy to assess the effectiveness of their attacks. At a time when UK service personnel are no longer deployed in Afghanistan, there will be scope to review the content of the report with key stakeholders, with a view to potentially including more information.

The data includes Royal Navy/Royal Marines, army including those from the Gibraltar regiment, and RAF personnel. Reservist personnel are included if they sustain an amputation, or an injury leading to an amputation, whilst on operations. Civilians and other nations service personnel have been excluded.

For reservist personnel that sustain an amputation whilst not deployed on operations there is often little information on when the amputation took place and whether it occurred whilst during service in the military, therefore these personnel are excluded. Please note that reservist personnel not undertaking MOD tasks receive their primary medical care from the NHS and any information entered in an NHS record is not held by MOD.

In reference to the UK Statistics Authority report, The Use Made of Official Statistics, the UK service personnel amputations statistics are used by:

• Government – Policy Making and Service Delivery
• Charities – Service Delivery

The key strength of this report is the combining of multiple sources to provide a complete picture on the number partial and full traumatic and surgical amputees.

The key weaknesses of this report are the restrictions on the amount of information that can be provided on the type of amputations seen.

Users are encouraged to provide feedback on the publication itself and Defence Statistics also welcome feedback from any other internal and external customers. Defence Statistics seek advice from key internal stakeholders to ensure the commentary provided helps to adequately explain the trends seen in the data for users.

6. Accuracy and Reliability

6.1 Overall Accuracy

Defence Statistics use nine sources of data to collate the amputation statistics for the period from 1 April 2006 onwards. It is therefore unlikely that an operational in-service amputee will not be picked up in one of these datasets and the figures presented are accurate. Most of the database sources used to compile this report do not cover the period prior to 1 April 2006. Therefore, operational in-service amputees have been sourced from the dataset used in a research paper (Dharm-datta et al., 2011). Defence Statistics are unable to validate this data against other sources, but it is the most accurate data held by the MOD.

The main sources of potential error in this official statistic are as follows:

• Incomplete or inaccurate data.
• Manual error during production of report.
• Data entered as free text: within DMICP any free text information is not pulled through to the data warehouse and therefore not interrogated; for AFCS, Health & Safety and DJEP any information entered incorrectly or misspelt may not have been captured.

Records from DMICP relating to amputations are cross referenced with all of the other data sources and only included if there is enough supporting evidence to confirm the incident and whether it was sustained in service. Please note that a service person’s prior medical history can be loaded into their DMICP medical records upon joining the armed forces, and it is not always possible to tell from the DMICP data warehouse whether an amputation read code relates to an amputation which was sustained in service.

In a few cases where records did not include a date of amputation, the date of incident has been used.

6.2 Data Revisions

The amputation statistics are subject to revisions as the amputations data is a live data system continually updated. Doctors may recommend and/or patients may elect to have an amputation at any point during their care pathway. As a result, any additional live UK service personnel identified as an amputee from our data sources have been included in this report. Any amendments made since the last release have been indicated by an ‘r’ in the statistical bulletin, and with annotations within the supplementary tables.

Data revisions are handled in accordance with the MOD’s Official Statistics Revisions and Corrections Policy.

7. Timeliness and Punctuality

7.1 Timeliness

The annual statistic is published on 31st July (or nearest available date) of each year following the ‘Medical Discharges in the UK regular armed forces’ report. This enables Defence Statistics to provide an update of the number of UK service personnel amputees medically discharged. Data is requested from the relevant suppliers in the first few days after the end of the latest financial year. It takes approximately 3 to 4 weeks for the data to be collected, returned to our IT team, pseudo-anonymised, processed and the report produced.

The amputation figures presented in Tables 1 to 3 are by the financial year an amputation was sustained, for patients that have a surgical and/or elective amputation this may not be in the same year in which the injury was sustained. If a UK service person suffers more than one amputation over a period of time they will be counted within the year where they sustained their first amputation. In the significant multiple amputees (SMA), Table 4, individuals are counted in the financial year in which they become an SMA.

All external publication deadlines have been met. Historic and planned publication dates can be found on the publication release dates section of the Defence Statistics website and on the UK National Statistics Publication Hub.

The report was previously presented by calendar years but was changed to present by financial year in December 2010 at the request of Surgeon General, to align with the Defence planning and business cycle. Historical publications that were produced by calendar year were removed from the website to avoid the potential for suppressed figures to be derived from totals.

7.2 Punctuality

The release date of this report been announced on the Release Calendar in accordance with the guidelines set out in the Code of Practice for Official Statistics.

The publication date is pre-announced on the GOV.UK Official Statistics Release Calendar.

8. Coherence and Comparability

The Defence Statistics figures on amputations to UK service personnel are the definitive statistics in the MOD. There are no other publicly available regular publications on the numbers of amputees with which to ensure coherence.

Statistics on coalition amputees can be found on the internet although the definitions used for amputations differ, or are at least unclear on how they’re counted, making it difficult to compare trends with other nations.

The numbers of UK service personnel suffering amputations are comparable over time as there have not been any changes in the way amputees are defined or counted. Changes seen over time are merely reflective of changes in operational tempo and tactical approach as operations in Iraq and Afghanistan have progressed.

The MOD has previously published statistics on seriously injured British casualties in Afghanistan, which provided the number of casualties with a Notification of Casualty (NOTICAS) signal raised of Very Seriously Injured (VSI) and Seriously Injured (SI). The peaks in VSI and SI numbers follow the same trend as the amputation statistics, with the highest numbers occurring in 2009 and 2010 when operational tempo was highest.

9. Accessibility and Clarity

9.1 Accessibility

Amputation statistics are published on the Statistics at MOD website. The publications are available from 09:30 hours on the day of release.

24-hour pre-release access to the report is available to a limited distribution list within the MOD. The full list can be found in the pre-release access list which is available on the GOV.UK website.

9.2 Clarity

Users with an interest in the key findings can read a short summary of main messages immediately at the beginning of the bulletin.

10. Trade-offs between Output Quality Components

The main trade-off is between the level of information presented in the output, without breaching medical confidentiality or compromising operational security.

The MOD are committed to making information on operational casualties public but must draw a line between how much information is provided regularly in the public domain and information which compromise operational security of UK armed forces personnel or which risks breaching an individual’s right to medical confidentiality.

11. Performance, Cost and Respondent Burden

To develop each annual report, it takes approximately 0.1 FTE to perform the analysis and compile the report. The burden on the data providers is low as the databases are updated routinely and they just provide us with the latest cut of data when we request it. Respondent burden is low as the data is obtained from administrative and clinical audit systems. These systems are maintained by other teams in Defence Statistics and MOD.

12. Confidentiality and Security

12.1 Confidentiality – Policy

All Defence Statistics (Health) staff involved in the production of the amputation statistics has signed a declaration that they have completed the government wide Protecting Information Level 1 training and they understand their responsibilities under the Data Protection Act and the Official Statistics Code of Practice. All MOD, civil service and data protection regulations are adhered to. The data is stored, accessed, and analysed using the MOD’s restricted network and IT systems. The databases supplied by our external customers are password protected.

Defence Statistics Health also adhere to Joint Service Publication 200 (October 2017). Defence Statistics Health ensure that the data is kept confidential by holding this data on a secure server. Only individuals who work on the reports have access to the data.

Defence Statistics Health adhere to the principles and protocols laid out in the Code of Practice for Official Statistics and comply with pre-release access arrangements. The Defence Statistics pre-release access lists are available on the GOV.UK website.

12.2 Confidentiality – Data Treatment

Prior to analysis data sources have been linked using a pseudo-anonymisation process. The individual identifiers were stripped from datasets and replaced by a pseudo-anonymiser, generated, effectively, by an automated sequential numbering system. The key to the system is that it recognises previous occurrences of a given service number and allocates the same pseudo-anonymiser on each occasion. This also enables the data to be linked with the other data sources, which have also already been pseudo-anonymised. The pseudo-anonymisation process can only be reversed in exceptional circumstances controlled by the Caldicott Guardian under strict protocols.

12.3 Security

Data in service number format is stored in password secured files so that they are only accessible by those with permission.

The data is held on MOD servers in accordance with JSP 440, Defence Manual of Security and Resilience.