NHS Digital Data Release Register - reformatted

Liverpool University Hospitals NHS Foundation Trust

Project 1 — DARS-NIC-170867-M5Q6W

Opt outs honoured: Yes - patient objections upheld (Section 251 NHS Act 2006)

Sensitive: Non Sensitive

When: 2019/11 — 2019/11.

Repeats: One-Off

Legal basis: Health and Social Care Act 2012 – s261(7)

Categories: Anonymised - ICO code compliant


  • Civil Registration - Deaths


The Royal Liverpool and Broadgreen University Hospitals NHS Trust (RLBUHT) requires Civil Registry mortality data which has been linked to National Vascular Registry (NVR) data for the purpose of a research study which aims to (1) develop a clinical decision tool based on the Aneurysm Repair Decision Aid (ARDA) and (2) to validate ARDA using the data. RLBUHT will be the sole Data Controller and the sole Data Processor. Abdominal aortic aneurysm (AAA) is a ballooning of the main artery of the body. Aneurysms gradually grow in size until some of them burst (rupture), at which point 80% are fatal. Aneurysm rupture is responsible for around 6,000 deaths per year in the UK, approximately 2.5% of all deaths in men over the age of 65 years. Each year approximately 6,000 patients undergo aneurysm repair in the UK with the aim of preventing premature death due to rupture. Aneurysm repair, however, is a major operation with a risk of serious complications and death. Whether or not a patient benefits from a planned AAA repair depends upon a balance between A) estimated survival of the patient if not for an aneurysm, B) risk of aneurysm rupture (if not repaired) that could be fatal, and C) the risk complications and death from the aneurysm repair. There is no practicable and consistent method of determining these factors for each patient in standard clinical practice. Therefore, in general, all patients with an aneurysm larger than 55 mm are considered for operation, and people with smaller aneurysms are simply observed with periodic scans. Such a "one size fits all" rule has the advantage of simplicity, but it is also generally accepted that a refined and personalised clinical decision process would serve patients and physicians better. Aneurysm Repair Decision Aid (ARDA) has been developed for this purpose. ARDA (Aneurysm Repair Decision Aid) is an NIHR project which was developed to identify optimal timing of elective abdominal aortic aneurysm repair (AAA) to achieve optimum survival advantage for individual patients and to assess the cost-effectiveness of elective repair at a particular aneurysm diameter. This allows a consistent and objective estimation of the pros and cons of operation for a patient, thus helping patients and surgeons decide on the best treatment strategy for individual patients. It is hoped ARDA will be useful in identifying which patients may benefit from repair even before an aneurysm reaches 55 mm in size and also who may be better served by observation despite having an aneurysm larger than 55 mm. This information would improve decision making for patients with aneurysms. However, ARDA has not been externally validated to be utilised in clinical practise. The vascular research team at Royal Liverpool and Broadgreen University Hospitals NHS Trust (RLBUHT) aims to develop a clinical decision tool based on ARDA and to conduct external validation among AAA patients in the National Vascular Registry (NVR) and also to estimate the potential impact of routine utilisation of this tool upon vascular services. The research will focus on two sets of patients: 1) Patients with aneurysms smaller than 55 mm, and 2) patients with aneurysms larger than 55 mm. RLBUHT has designed an analysis to validate ARDA prediction model based on a retrospective analysis of patients registered in the National Vascular Registry (NVR) who underwent elective repair of an AAA in England and Wales between January 2012 and December 2015, who are over 18 and have not undergone previous aortic surgery. Based on the health data of these patients as held on the NVR, RLBUHT shall undertake survival analyses under a hypothetical scenario of each patient's management guided by ARDA. The patients will be divided into two cohorts, one in whom ARDA supports immediate elective AAA repair (ARDA-OP group) and the other in whom ARDA suggests continued observation or non-operative management (ARDA-BMT group) (BMT = Best medical therapy). RLBUHT intend to statistically compare estimated survival against observed survival in both groups of patients. This analysis requires medium / late-term survival information of these patients, which is not available from the NVR. Therefore, RLBUHT requires access to linked Civil Registry data (mortality data) for these patients through NHS Digital. This study is being funded by Liverpool Vascular and Endovascular Services' (LiVES) Vascular Aneurysm research fund. LiVES is a service within the . The study is being conducted by researchers in the vascular unit of the Royal Liverpool and Broadgreen University Hospitals NHS Trust. RLBUHT has designed the data flow and data management in a least intrusive manner that does not require the research team to access identifiable patient information or sensitive data. RLBUHT are requesting record-level linkage of survival information sourced from NHS Digital civil registry data, with health data from the NVR sourced by Healthcare Quality Improvement Partnership (HQIP). This will be done by NHS Digital acting as a trusted-third-party and dates are truncated to month/year to achieve this. This work is research in the public interest as it aims to improve care and clinical outcome for all patients who have an AAA, regardless of size, by providing a refined and personalised clinical decision-making process, serving patients and clinicians better. RLBUHT has determined that there are no moral or ethical issues from dissemination of data for this purpose. NHS Digital will pseudonymise the data before it is disseminated and RLBUHT will therefore be compliant with the ICO's "Anonymisation: managing data protection risk" code of practice.

Expected Benefits:

This research will determine if the ARDA clinical decision tool can be utilised in clinical practice. This has a potential benefit for infra-renal AAA patients in the future as it will enable them to make an informed decision when it comes to the management of their aneurysm. Besides, it will identify the optimal timing of surgery for each patient to maximise survival and provide optimal clinical care. The economic evaluation suggested that using ARDA could be cost-effective compared to decision making solely by aneurysm size threshold. Once ARDA is externally validated, the cost effective measure will be discussed with health economic team. ARDA clinical decision tool will be useful in identifying which patients may benefit from repair even before an aneurysm reaches 55 mm in size and also who may be better served by observation despite having an aneurysm larger than 55 mm. The research project is anticipated to lead to a prospective national study to evaluate the impact of the ARDA-based clinical decision tool on the treatment of abdominal aortic aneurysms. Royal Liverpool and Broadgreen University Hospitals NHS Trust envisage the publication of the result of this project by February 2020. RLBUHT has appointed a Patient and Public involvement (PPI) group for the purpose of this project. The Chief Investigator and Co-Investigator met with this group to discuss the project and the accessibility of using patient identifiable data by the NHS digital. The PPI group had no objections regarding accessing patient identifiable data by NHS Digital and considered this project to be an excellent project that will produce a powerful decision tool which will help the patients understand the risk and benefit from the AAA repair and enable both the surgeons and the patients to make an inform decision. There are three representative patients in the PPI group and the RLBUHT will conduct regular meeting with them to provide them with an update of the project progress and results.


This study will determine if the clinical binary decision tool developed by RLBUHT can be used to externally validate ARDA for the management of abdominal aortic aneurysm for both surgeons and patients. As for any clinical risk predictive model, .external validation is essential for it to be utilised in clinical practise. Once ARDA has been externally validated using the clinical binary decision tool, the findings will be submitted for presentation in the Vascular Society for Great Britain and Ireland Annual Scientific Meeting. The findings will also be submitted for publication in a reputable journal such as The Lancet, Journal of Vascular Surgery and European Journal of Vascular and Endovascular Surgery. In addition, the report will be forwarded to Health Research Authority. This output will contribute to conducting a subsequent national prospective study utilising the binary decision tool in management of patient with abdominal aortic aneurysm which is necessary for this tool to be adopted in clinical practice. All outputs will only contain data which is aggregated with small numbers suppressed in line with the HES Analysis Guide. RLBUHT anticipate the results will be available for publication by 01/02/2020.


This study is conducted by researchers in the Royal Liverpool and Broadgreen University Hospitals NHS Trust. Data Sources: 1) The National Vascular Registry (NVR): Health data and postoperative death date 2) Civil registration data from NHS Digital. Data flow will take the following steps: 1) Patients included in the NVR and identified to have undergone an elective AAA repair between 01/01/2012 and 31/12/2015, who are over 18 and have not undergone previous aortic surgery will be determined by HQIP's data processor and extracted; 2) Patient identifiable Health data extracted from NVR will include NHS number and date of birth; 3) HQIP's data processor will send the patient-identifiable NVR data (Study ID, NHS number and date of birth) to NHS Digital; 4) NHS Digital will link the NVR data to the Civil Registration data and will then remove all identifying personal information; 5) NHS Digital will pseudonymise the data and send a summary of death information (Date of death, truncated to mm/yyyy and cause of death code), with the Study ID directly to the Royal Liverpool University Hospital research team. In addition, NVR will also create a pseudonymised dataset, including wider clinical information, using the same study ID and transfer this direct to the Royal Liverpool and Broadgreen University Hospitals NHS Trust. Royal Liverpool and Broadgreen University Hospitals NHS Trust would link both datasets via the study ID. The combined pseudonymised data set will be securely stored for five years from the date of receiving the data, in line with research data policies set out by the Journal of Vascular Surgery and European Journal of Vascular and Endovascular surgery. To clarify, NVR will not send any patient identifying data directly to RLBUHT. NHS Digital team will act as a trusted-third-party for linking NVR data with Civil Registration mortality data and pseudonymising the data. Steps therefore have been taken to mitigate the risk of any re-identification. The research study team will not share the data with any third party. Data will be analysed by the research team in the RLBUHT. The data will be analysed and stored in a password protected electronic file in RLBUHT secured network. Access to this file will be further protected by hospital network log-in. Access will be restricted to the investigators only. Following completion, the pseudonymised database will be transferred to the Chief Investigator and stored on his password-protected NHS computer, which is in a locked non-clinical area within the Royal Liverpool University Hospital. All organisations party to this agreement must comply with the Data Sharing Framework Contract requirements, including those regarding the use (and purposes of that use) by “Personnel” (as defined within the Data Sharing Framework Contract - i.e. employees, agents and contractors of the Data Recipient who may have access to that data). No data will be shared with third parties. The Data will only be used for the purposes described in this Agreement.