Knowledge Synthesis

Knowledge Synthesis

Knowledge Synthesis

We lead the health economics component of health technology assessments undertaken across the IAHS. These include our NIHR funded Technology Assessment Reviews (TARs) work, other NIHR funded and externally funded trials and cohort studies of new and existing interventions. The research is generally multidisciplinary and undertaken in collaboration with research groups in the University of Aberdeen and external centres of excellence.

Current Projects

TARs - NIHR Technology Assessment Reviews

The University of Aberdeen, through the Aberdeen Health Technologies Assessment (HTA) Group, are one of the independent centres with an NIHR (National Institute for Health and Care Research) Technology Assessment Reviews (TARs) contract to review evidence for the development of technology appraisals guidance.

The Aberdeen HTA Group is a multidisciplinary team from HERU, the Health Services Research Unit (HSRU) and Medical Statistics

Under the TARs contract the Aberdeen HTA Group synthesise evidence on the clinical and cost-effectiveness of health technologies and provide information to support the development of healthcare policy by the National Institute for Health and Care Excellence (NICE) and other NHS and governmental organisations. The group also develop and refine methods of HTA. The Aberdeen HTA Group have held a TARs contract since 2001. The contract has been renewed for the 2022-26 period.

HERU Researchers: Graham Scotland and Dwayne Boyers

Other Collaborators: C. Ramsay, M. Brazzelli, M. Campbell (Health Services Research Unit (HSRU), University of Aberdeen); L. Aucott, N. Scott, (Medical Statistics Team, Institute of Applied Health Sciences, University of Aberdeen)

TESTES - Testosterone Effects and Safety

TESTES - Effects and safety of testosterone in Men with low testosterone levels: an evidence synthesis and economic evaluation

Testosterone hormone is vital for sexual activity, bone growth and muscle development in men. Low testosterone levels may result in sexual problems, osteoporosis, weakness, low mood and tiredness. These symptoms can be treated with ART. Prescriptions of ART in men have nearly doubled within the last 10 years in the UK, yet the incidence of symptomatic men with low testosterone levels remains unchanged. Besides, there is conflicting evidence on the clinical effectiveness of ART with some studies suggesting a potential increased risk of cardiovascular events and prostate growth.

This project has three main components: 1) a systematic literature review (SLR) will identify relevant randomized controlled trials (RCTs), 2) a second SLR will be used to synthetize the existing qualitative evidence reporting men’s experience and acceptability of ART and 3) the development of a decision model to estimate the cost-effectiveness of ART for the treatment of symptomatic men with low testosterone.

As part of the project individual patient data (IPD) from relevant RCTs will be retrieved. The meta-analysis of these data will provide crucial inputs for the economic model.

HERU researchers involved in this research project: Rodolfo Hernández 

External collaborators: C. Jayasena (Imperial College of Science, Technology and Medicine); W. Dhilo (Imperial College London); F. Wu (University of Manchester); S. Bhattacharya, K. Gillies, M. Brazzelli, L. Aucott (University of Aberdeen); R. Quinton (Freeman Hospital); N. Oliver (Imperial College London)


Recently Completed Projects

EVAR - Surveillance following Endovascular Aortic aneurysm Repair

The clinical and cost-effectiveness of protocols using contrast-enhanced ultrasound and/or colour duplex ultrasound in the long-term surveillance of endovascular abdominal aortic aneurysm repair

An abdominal aortic aneurysm is a swelling or bulge that causes the wall of the main blood vessel (aorta) to weaken and become pouched or sac-shaped. Large aneurysms can burst, causing massive internal bleeding, which can lead to death. EVAR of the aneurysm has become the preferred treatment option for abdominal aortic aneurysm. EVAR is minimally invasive but it is associated with potential complications of which the most common is the occurrence of an endoleak (blood flow in the aneurysm sac). Consequently, patients who receive EVAR treatment must be followed up for the rest of their life.

CTA is an imaging modality widely used for the surveillance after EVAR. CTA is considered to be very accurate but it is not very good at detecting the direction of blood flow from an endoleak. It also carries the risk of repeated exposure to radiation and to a toxic contrast agent. CDU and CEU have been suggested as possible safer imaging alternatives to CTA but have not been widely adopted. The optimal surveillance strategy with regard to the choice of imaging modalities and the frequency of testing has not been established yet.

This study included a systematic review of the literature to assess the current evidence for the clinical effectiveness and cost-effectiveness of surveillance strategies using CDU and CEU compared with CTA in the surveillance after EVAR. A model based economic evaluation was also conducted as part of the assessment. Publication of the final report is currently pending.

The results of the project will be used by the National Institute for Health and Care Excellence (NICE) to issue clinical guidance in England and Wales on the optimal surveillance strategy after EVAR.

This review is registered with PROSPERO International prospective register of systematic reviews (PROSPERO 2016:CRD4201603475).

Outcome and Translation

The findings from this study will be available to help inform clinical guidelines and research recommendations on surveillance following EVAR.

HERU researchers involved in this research project: Graham Scotland and Rodolfo Hernández

External collaborators: C Ramsay, M Brazelli, M Campbell (HSRU, University of Aberdeen)

Oral splints for orofacial symptoms: an evidence synthesis

Oral splints are placed by dentists working in the NHS for patients with orofacial signs of symptoms. It is unclear if oral splints are effective or cost-effective, and if they are, which type of splint is the most cost-effective (cheaper pre-fabricated splints or more expensive custom made ones). 

This project developed a Markov decision analysis model alongside a systematic review of the clinical effectiveness literature on the use of oral splints for temporomandibular disease (TMD).

Standard reporting methods were used to illustrate uncertainty in findings (deterministic and probabilistic sensitivity analysis). There was a dearth of high quality evidence to populate the model, particularly over the longer time period. An expected value of perfect information (EVPI) analysis explored the value for money of conducting additional research to resolve uncertainty in the cost-effectiveness evidence. Expected value of partial perfect information (EVPPI) analysis was used to identify the most important model parameters on which to obtain future data. The results of these analyses can help to prioritise key areas of future research from a cost-effectiveness view-point.

Outcome and Translation

Results of the trial are currently under submission to journals. 

HERU researchers involved in this research project: Dwayne Boyers and Elisabet Jacobsen

External collaborators: Worthington, H., Glenny, A-M. Riley, P. (University of Manchester); Robertson, C. (HSRU, University of Aberdeen).

A self-contained Appendix to the report is available. This Appendix is not part of the main report but informs the findings.