Economic evaluations for health technologies with an evolving evidence base: a case study of transcatheter aortic valve implantation

The primary aim of this thesis is to investigate the challenges in conducting economic evaluations for medical devices with evolving evidence bases. While economic evaluations for capital projects and medicines are well established in theory and practice, the same cannot be said for novel medical devices. New medical devices are often expensive and rely on scarce evidence for efficacy and cost. This increases uncertainty surrounding their clinical and cost effectiveness. In addition, as fewer formal procedures exist for evaluating devices relative to medicines, evidence bases are weak and health technology assessment agencies are reluctant to make rapid decisions. To address these issues a continuous iterative framework developed and proposed for economic evaluations of medical devices. In this thesis, using Transcatheter Aortic Valve Implantation (TAVI) as a case study, an iterative economic evaluation, employing Bayesian techniques, is developed to investigate how the challenges associated with medical devices can be overcome to produce an efficient and informative economic evaluation. This study is the first to investigate these challenges and identify solutions while conducting an economic evaluation early in a device’s life cycle, using the proposed continuous iterative framework. The consideration of Access with Evidence Development schemes to overcome these challenges and balance access with evidence generation for expensive and novel medical devices, with evolving evidence, is another important contribution of the thesis. Transcatheter Aortic Valve Implantation (TAVI) is a novel treatment for severe Aortic Stenosis for operable and inoperable patients. The iterative economic evaluation concludes that TAVI can be considered cost effective for inoperable patients compared to medical management. There is little value in commissioning new research for continued data collection for this group. However, the continued collection of evidence via the UK TAVI registry as indicated in the National Institute of Clinical Excellence (NICE) guidelines will ensure up to date evidence is available to inform future decisions regarding TAVI in this patient group. For operable patients, the iterative model could not conclude that TAVI was cost effective compared to Aortic Valve Replacement (AVR). However, additional evidence of improved outcomes from TAVI should enhance its cost effectiveness for these patients. The Bayesian value of information analysis indicates that further information on short and long term probability, resource and quality of life parameters is most valuable and the optimal research design for collecting such information is a registry

The safety climate in primary care (SAP-C) study: study protocol for a randomised controlled feasibility study

BACKGROUND: Research on patient safety has focused largely on secondary care settings, and there is a dearth of knowledge relating to safety culture or climate, and safety climate improvement strategies, in the context of primary care. This is problematic given the high rates of usage of primary care services and the myriad of opportunities for clinical errors daily. The current research programme aimed to assess the effectiveness of an intervention derived from the Scottish Patient Safety Programme in Primary Care. The intervention consists of safety climate measurement and feedback and patient chart audit using the trigger review method. The purpose of this paper is to describe the background to this research and to present the methodology of this feasibility study in preparation for a future definitive RCT. METHODS: The SAP-C study is a feasibility study employing a randomised controlled pretest-posttest design that will be conducted in 10 general practices in the Republic of Ireland and Northern Ireland. Five practices will receive the safety climate intervention over a 9-month period. The five practices in the control group will continue care as usual but will complete the GP-SafeQuest safety climate questionnaire at baseline (month 1) and at the terminus of the intervention (month 9). The outcomes of the study include process evaluation metrics (i.e. rates of participant recruitment and retention, rates of completion of safety climate measures, qualitative data regarding participants’ perceptions of the intervention’s potential efficacy, acceptability, and sustainability), patient safety culture in intervention and control group practices at posttest, and instances of undetected patient harm identified through patient chart audit using the trigger review method. DISCUSSION: The planned study investigates an intervention to improve safety climate in Irish primary care settings. The resulting data may inform our knowledge of the frequency of undetected patient safety incidents in primary care, may contribute to improved patient safety practices in primary care settings, and may inform future research on patient safety improvement initiatives. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40814-016-0096-5) contains supplementary material, which is available to authorized users

Promoting men’s awareness, self-examination, and help-seeking for testicular disorders: a systematic review of interventions [version 2; referees: 2 approved]

Background: Testicular cancer (TC) is commonly diagnosed among men aged 15-40 years. The incidence of TC is on the rise. Benign testicular disorders such as testicular torsion and epididymitis can lead to testicular ischemia, sepsis, and infertility if left untreated. This systematic review aims to evaluate the effectiveness of studies promoting menâ s knowledge and awareness of testicular disorders and/or self-examination, behaviours and/or intentions to examine their testes, and help-seeking behaviours and/or intentions for testicular symptoms. Methods: Academic Search Complete, Medline, CINAHL, PsychINFO, ERIC, the Cochrane Library, the World Health Organisation International Clinical Trials Registry Platform, Clinicaltrials.gov, Grey Literature Report, and Open Grey were searched for studies published between November 2014 and April 2018. The methodological quality and level of evidence per outcome were assessed. Results: There were five papers included: two were experimental studies, two were systematic reviews, and one was an integrative review. The majority of the reviewed interventions were successful in increasing menâ s awareness of TC and self-examination. Examples include a television show featuring a celebrity with TC, a university campaign, and interactive educational sessions. The impact of the reviewed interventions on health beliefs (i.e. perceived susceptibility, severity, benefits, barriers, and self-efficacy) varied across the reviewed literature. Studies promoting help-seeking for testicular symptoms and awareness of benign testicular disorders were lacking. Conclusions: This review highlights the importance of evaluating educational interventions aimed at younger men, whilst raising their awareness of testicular disorders and increasing their help-seeking intentions for testicular symptoms. Given the lack of consensus around scheduled testicular self-examination among younger men, clinicians are encouraged to instruct men to familiarise themselves with the look and feel of their own testes and to seek timely medical attention for abnormalities

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

Background: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. Methods: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). Findings: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29–146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0– 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25–1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39–1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65–1·60]; p=0·92). Interpretation: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention

Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

Background: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. Methods: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). Findings: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29–146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0– 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25–1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39–1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65–1·60]; p=0·92). Interpretation: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention

Effects of antiplatelet therapy after stroke due to intracerebral haemorrhage (RESTART): a randomised, open-label trial

BACKGROUND: Antiplatelet therapy reduces the risk of major vascular events for people with occlusive vascular disease, although it might increase the risk of intracranial haemorrhage. Patients surviving the commonest subtype of intracranial haemorrhage, intracerebral haemorrhage, are at risk of both haemorrhagic and occlusive vascular events, but whether antiplatelet therapy can be used safely is unclear. We aimed to estimate the relative and absolute effects of antiplatelet therapy on recurrent intracerebral haemorrhage and whether this risk might exceed any reduction of occlusive vascular events. METHODS: The REstart or STop Antithrombotics Randomised Trial (RESTART) was a prospective, randomised, open-label, blinded endpoint, parallel-group trial at 122 hospitals in the UK. We recruited adults (≥18 years) who were taking antithrombotic (antiplatelet or anticoagulant) therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage, discontinued antithrombotic therapy, and survived for 24 h. Computerised randomisation incorporating minimisation allocated participants (1:1) to start or avoid antiplatelet therapy. We followed participants for the primary outcome (recurrent symptomatic intracerebral haemorrhage) for up to 5 years. We analysed data from all randomised participants using Cox proportional hazards regression, adjusted for minimisation covariates. This trial is registered with ISRCTN (number ISRCTN71907627). FINDINGS: Between May 22, 2013, and May 31, 2018, 537 participants were recruited a median of 76 days (IQR 29-146) after intracerebral haemorrhage onset: 268 were assigned to start and 269 (one withdrew) to avoid antiplatelet therapy. Participants were followed for a median of 2·0 years (IQR [1·0- 3·0]; completeness 99·3%). 12 (4%) of 268 participants allocated to antiplatelet therapy had recurrence of intracerebral haemorrhage compared with 23 (9%) of 268 participants allocated to avoid antiplatelet therapy (adjusted hazard ratio 0·51 [95% CI 0·25-1·03]; p=0·060). 18 (7%) participants allocated to antiplatelet therapy experienced major haemorrhagic events compared with 25 (9%) participants allocated to avoid antiplatelet therapy (0·71 [0·39-1·30]; p=0·27), and 39 [15%] participants allocated to antiplatelet therapy had major occlusive vascular events compared with 38 [14%] allocated to avoid antiplatelet therapy (1·02 [0·65-1·60]; p=0·92). INTERPRETATION: These results exclude all but a very modest increase in the risk of recurrent intracerebral haemorrhage with antiplatelet therapy for patients on antithrombotic therapy for the prevention of occlusive vascular disease when they developed intracerebral haemorrhage. The risk of recurrent intracerebral haemorrhage is probably too small to exceed the established benefits of antiplatelet therapy for secondary prevention. FUNDING: British Heart Foundation

Genomic epidemiology of SARS-CoV-2 in a UK university identifies dynamics of transmission

AbstractUnderstanding SARS-CoV-2 transmission in higher education settings is important to limit spread between students, and into at-risk populations. In this study, we sequenced 482 SARS-CoV-2 isolates from the University of Cambridge from 5 October to 6 December 2020. We perform a detailed phylogenetic comparison with 972 isolates from the surrounding community, complemented with epidemiological and contact tracing data, to determine transmission dynamics. We observe limited viral introductions into the university; the majority of student cases were linked to a single genetic cluster, likely following social gatherings at a venue outside the university. We identify considerable onward transmission associated with student accommodation and courses; this was effectively contained using local infection control measures and following a national lockdown. Transmission clusters were largely segregated within the university or the community. Our study highlights key determinants of SARS-CoV-2 transmission and effective interventions in a higher education setting that will inform public health policy during pandemics.</jats:p

Additional file 1: of The safety climate in primary care (SAP-C) study: study protocol for a randomised controlled feasibility study

Invitation letters, participant information sheets, and statement of consent forms. (DOCX 45 kb