An exploratory assessment of the impact of a novel risk assessment test on breast cancer clinic waiting times and workflow: a discrete event simulation model.

BACKGROUND: Breast cancer clinics across the UK have long been struggling to cope with high demand. Novel risk prediction tools - such as the PinPoint test - could help to reduce unnecessary clinic referrals. Using early data on the expected accuracy of the test, we explore the potential impact of PinPoint on: (a) the percentage of patients meeting the two-week referral target, and (b) the number of clinic 'overspill' appointments generated (i.e. patients having to return to the clinic to complete their required investigations). METHODS: A simulation model was built to reflect the annual flow of patients through a single UK clinic. Due to current uncertainty around the exact impact of PinPoint testing on standard care, two primary scenarios were assessed. Scenario 1 assumed complete GP adherence to testing, with only non-referred cancerous cases returning for delayed referral. Scenario 2 assumed GPs would overrule 20% of low-risk results, and that 10% of non-referred non-cancerous cases would also return for delayed referral. A range of sensitivity analyses were conducted to explore the impact of key uncertainties on the model results. Service reconfiguration scenarios, removing individual weekly clinics from the clinic schedule, were also explored. RESULTS: Under standard care, 66.3% (95% CI: 66.0 to 66.5) of patients met the referral target, with 1,685 (1,648 to 1,722) overspill appointments. Under both PinPoint scenarios, > 98% of patients met the referral target, with overspill appointments reduced to between 727 (707 to 746) [Scenario 1] and 886 (861 to 911) [Scenario 2]. The reduced clinic demand was sufficient to allow removal of one weekly low-capacity clinic [N = 10], and the results were robust to sensitivity analyses. CONCLUSION: The findings from this early analysis indicate that risk prediction tools could have the potential to alleviate pressure on cancer clinics, and are expected to have increased utility in the wake of heightened pressures resulting from the COVID-19 pandemic. Further research is required to validate these findings with real world evidence; evaluate the broader clinical and economic impact of the test; and to determine outcomes and risks for patients deemed to be low-risk on the PinPoint test and therefore not initially referred.

The cost-effectiveness of using rapid diagnostic tests for the diagnosis of typhoid fever in patients with suspected typhoid fever: a systematic review.

INTRODUCTION: Despite the availability of several commercial rapid diagnostic tests (RDTs) developed to detect typhoid fever, the cost-effectiveness in resource-limited settings is unclear. This review aimed to explore the literature on typhoid economic evaluations in order to assess the cost-effectiveness of using typhoid RDTs in resource-limited settings. AREAS COVERED: A systematic review was conducted focusing on the identification of economic evaluations of typhoid RDTs to diagnose patients with suspected typhoid fever. Two studies were identified and included for narrative synthesis. Whilst highlighting a gap in the published literature, this review shows the use of typhoid RDTs to potentially be cost-effective in resource-limited settings. Factors that appeared as significant in determining cost-effectiveness related to test characteristics (such as sensitivity, specificity, and cost) and the prevalence of typhoid fever and should factor into any future evaluations. EXPERT OPINION: Concerted effort is needed in resource-limited settings with regard to medical device regulation to ensure that clinically effective and cost-effective typhoid RDTs are widely available and introduced into clinical practice. Typhoid modeling (with respect to typhoid testing and treatment strategies) represents an understudied area and further work is needed.

Early economic evaluation of an intervention to improve uptake of the NHS England Diabetes Prevention Programme.

BACKGROUND: Despite reported increases in referral numbers, a large proportion of those with prediabetes still decline participation in the NHS England Diabetes Prevention Programme (NDPP). The aim of this study was to explore whether investment in interventions to improve uptake of the programme has the potential to be cost-effective. METHODS: An early cost-utility analysis was conducted using a Markov model parameterized based on secondary data sources. We explored different uptake scenarios and the impact that this had on the maximum allowable intervention price based on cost-effectiveness at the UK NICE willingness to pay threshold of £20,000 (US$ 25,913). Value of information analyses were conducted to explore the potential value of further research to resolve uncertainty at each uptake level. RESULTS: As uptake levels increase, the maximum allowable intervention price and overall expected value of removing decision uncertainty increases. For 5 percentage and 50 percentage points increase in uptake levels, the maximum allowable intervention price is £41.86 (US$ 54.23) and £418.59 (US$ 542.34) per person, and the overall expected value of removing decision uncertainty are £361,818,839 (US$ 468,786,625) and £1,468,712,316 (US$ 1,902,921,063) respectively. CONCLUSION: There is headroom for investment in interventions that improve uptake to the NDPP, thereby allowing the programme itself to be delivered in a manner that remains cost-effective.

Early Economic Evaluation to Identify the Necessary Test Characteristics of a New Typhoid Test to be Cost Effective in Ghana.

BACKGROUND: In Ghana, there are issues with the diagnosis of typhoid fever; these include delays in diagnosis, concerns about the accuracy of current tests, and lack of availability. These issues highlight the need for the development of a rapid, accurate, and easily accessible diagnostic test. The aim of this study was to conduct an early economic analysis of a hypothetical rapid test for typhoid fever diagnosis in Ghana and identify the necessary characteristics of the test for it to be cost effective in Ghana. METHODS: An early cost-utility analysis was conducted using a decision tree parameterized with secondary data sources, with reasonable assumptions made for unknown parameters. The patient population considered is individuals presenting with symptoms suggestive of typhoid fever at a healthcare facility in Ghana; a time horizon of 180 days and the Ghanaian national health service perspective were adopted for the analysis. Extensive sensitivity analysis was undertaken, including headroom analysis. RESULTS: The results here show that for a hypothetical test to perform better than the existing test (Widal) in terms of QALYs gained and cost effectiveness, it is necessary for it to have a high specificity (at least 70%) and should not be priced more than US$4. The overall value of conducting research to reduce uncertainty (over 5 years) is US$3287. CONCLUSION: The analysis shows the potential for the hypothetical test to replace the Widal test and the market potential of developing a new test in the Ghanaian setting.

Integrating Qualitative Techniques in Model Development: A Case Study Using the Framework Approach.

BACKGROUND: Despite their potential, there is limited uptake of formal qualitative methods in model development by modellers and health economists. The aim of this case study was to highlight in a real-world context how a qualitative approach has been applied to gain insight into current practice (delineating existing care pathways) for typhoid fever in Ghana, which can then assist in model structure conceptualisation in a model-based cost-effectiveness analysis. METHODS: The perspectives of a range of healthcare professionals working in different settings and across different practices in the Eastern region of Ghana were captured with a self-administered survey using open-ended questions and analysed using the framework method. RESULTS: A total of 51 completed questionnaires were retrieved representing a 73% response rate. It was found that two main care pathways for typhoid fever exist in Ghana and there was no consensus on how a new test might be applied to the existing pathways. CONCLUSION: The two settings in Ghana have different care pathways and any cost-effectiveness analysis should consider the alternative pathways separately. This study demonstrated that framework analysis is a qualitative methodology that is likely to be accessible and feasible across a wide range of health economic settings.

Economic evaluation of typhoid - a review.

INTRODUCTION: To evaluate the potential economic value and likely impact of a hypothetical rapid test in its early stages of development requires the use of models. The model structure and the type of model (dynamic/static) to employ are key considerations. The aim of the review was to explore the literature on typhoid economic evaluations and to explore the types of models that have been previously adopted in this setting for test-treat evaluations and to capture data on model inputs that may be useful for a de novo model. AREAS COVERED: A systematic review was conducted to identify economic evaluations focused on typhoid in established literature databases. Eight studies were identified and included for narrative synthesis. The review has revealed that there have been relatively few economic evaluations that have focused on typhoid fever, all of which have focused on the impact of interventions at the population level (vaccination) but not the individual level (test-treat strategies). EXPERT COMMENTARY: Under certain circumstances, either a static model or a transmission dynamic model may be appropriate in the evaluation of an intervention for typhoid fever. Typhoid test-treat modeling represents a gray area where further work is needed.

Economic evaluation of medical tests at the early phases of development: a systematic review of empirical studies.

INTRODUCTION: There is little specific guidance on the implementation of cost-effectiveness modelling at the early stage of test development. The aim of this study was to review the literature in this field to examine the methodologies and tools that have been employed to date. AREAS COVERED: A systematic review to identify relevant studies in established literature databases. Five studies were identified and included for narrative synthesis. These studies revealed that there is no consistent approach in this growing field. The perspective of patients and the potential for value of information (VOI) to provide information on the value of future research is often overlooked. Test accuracy is an essential consideration, with most studies having described and included all possible test results in their analysis, and conducted extensive sensitivity analyses on important parameters. Headroom analysis was considered in some instances but at the early development stage (not the concept stage). EXPERT COMMENTARY: The techniques available to modellers that can demonstrate the value of conducting further research and product development (i.e. VOI analysis, headroom analysis) should be better utilized. There is the need for concerted efforts to develop rigorous methodology in this growing field to maximize the value and quality of such analysis.

Economic evaluation alongside factorial trials: a systematic review of empirical studies.

Although economic evaluations have been performed alongside factorial trials, there seems to be limited guidance/consensus on appropriate methods of analysis. Following Centre for Review and Dissemination guidance, a systematic review of published literature for all years was performed to explore how economic evaluation alongside factorial trials have been conducted and only full economic evaluations conducted alongside factorial trials were included. A total of 16 relevant studies were identified, and an assessment of these indicated that two methods: within-the-table and at-the-margins approaches were used for the analysis. With the exception of one study, all others did not consider interactions in costs and outcomes or give a detailed explanation of why a particular approach was adopted. The authors recommend that additional guidance is needed, and further research is required to evaluate the impact of alternative methods on policy recommendations and establish good practice methods for the economic analysis of factorial trials.