Optimising the cost-effectiveness of risk-based screening for diabetic retinopathy

Publicly provided health screening programmes tend to offer standardised screening for a fixed eligible population. Recently, the development of risk calculation engines has introduced the potential for the stratification of screening based on individuals' risks of disease onset. This possibility raises practical, methodological, and ethical challenges. To date, no such programme has been the subject of an economic evaluation. In this thesis we present reason and basis for the allocation of screening based on individual risk. The research is conducted in the context of screening for diabetic eye disease in the UK. Diabetic retinopathy is a common complication of diabetes that can lead to blindness, substantial detriments to quality of life, and significant health care resource use. Our study is linked to a programme of research that includes a cohort study and randomised controlled trial in the city of Liverpool. We review and further develop the evidence base to inform the evaluation of a risk-based screening programme for diabetic eye disease. Specifically, we generate new evidence on the costs and health outcomes associated with the screening and treatment of diabetic retinopathy. We report on a cross-sectional study of health-related quality of life for people attending screening for diabetic retinopathy and find that people with pre-symptomatic disease tend to report poorer quality of life than people with no disease, with EQ-5D-5L index values of 0.733 on average compared with 0.787 for people with no disease. A meta-analysis of published health state utility values for diabetic eye disease shows a negative impact on health-related quality of life before progression to blindness. Our meta-regression found a utility index decrement of 0.024 for people with proliferative retinopathy. The costs of screening are low at the individual level, estimated to be £32.03 in our costing study. But the overall budget impact of changes in the frequency of screening can be significant. We analyse a large data set of hospital and community screening activity to identify key treatment pathways for diabetic eye disease. We find that these have changed in recent years, with the introduction of more expensive interventions. The evidence generated by our work is used to inform the development of a decision analytic model. The model is designed to estimate the cost-effectiveness of risk-based screening for diabetic eye disease, compared with current practice. We find that risk-based screening is likely to be more cost-effective than standardised screening programmes. Evaluating a programme that allocates screening according to individuals' levels of risk raises theoretical and ethical challenges. To this end, we develop a simple framework for individualised cost-effectiveness analysis that can be used to inform the design of a risk-based screening programme. We also explore the ethics of risk-based screening, developing the notion of screening need as distinct from treatment need. Risk-based screening is likely to be cost-effective in the context of diabetic eye disease. The evidence presented in this thesis can be used to support the evaluation of new programmes, which can be designed in order to optimise cost-effectiveness using the methods that we describe. Such an approach is consistent with equitable policy objectives

Optimising the cost-effectiveness of risk-based screening for diabetic retinopathy

Publicly provided health screening programmes tend to offer standardised screening for a fixed eligible population. Recently, the development of risk calculation engines has introduced the potential for the stratification of screening based on individuals' risks of disease onset. This possibility raises practical, methodological, and ethical challenges. To date, no such programme has been the subject of an economic evaluation. In this thesis we present reason and basis for the allocation of screening based on individual risk. The research is conducted in the context of screening for diabetic eye disease in the UK. Diabetic retinopathy is a common complication of diabetes that can lead to blindness, substantial detriments to quality of life, and significant health care resource use. Our study is linked to a programme of research that includes a cohort study and randomised controlled trial in the city of Liverpool. We review and further develop the evidence base to inform the evaluation of a risk-based screening programme for diabetic eye disease. Specifically, we generate new evidence on the costs and health outcomes associated with the screening and treatment of diabetic retinopathy. We report on a cross-sectional study of health-related quality of life for people attending screening for diabetic retinopathy and find that people with pre-symptomatic disease tend to report poorer quality of life than people with no disease, with EQ-5D-5L index values of 0.733 on average compared with 0.787 for people with no disease. A meta-analysis of published health state utility values for diabetic eye disease shows a negative impact on health-related quality of life before progression to blindness. Our meta-regression found a utility index decrement of 0.024 for people with proliferative retinopathy. The costs of screening are low at the individual level, estimated to be £32.03 in our costing study. But the overall budget impact of changes in the frequency of screening can be significant. We analyse a large data set of hospital and community screening activity to identify key treatment pathways for diabetic eye disease. We find that these have changed in recent years, with the introduction of more expensive interventions. The evidence generated by our work is used to inform the development of a decision analytic model. The model is designed to estimate the cost-effectiveness of risk-based screening for diabetic eye disease, compared with current practice. We find that risk-based screening is likely to be more cost-effective than standardised screening programmes. Evaluating a programme that allocates screening according to individuals' levels of risk raises theoretical and ethical challenges. To this end, we develop a simple framework for individualised cost-effectiveness analysis that can be used to inform the design of a risk-based screening programme. We also explore the ethics of risk-based screening, developing the notion of screening need as distinct from treatment need. Risk-based screening is likely to be cost-effective in the context of diabetic eye disease. The evidence presented in this thesis can be used to support the evaluation of new programmes, which can be designed in order to optimise cost-effectiveness using the methods that we describe. Such an approach is consistent with equitable policy objectives

An introduction to economic evaluation in occupational therapy: cost-effectiveness of pre-discharge home visits after stroke (HOVIS)

Introduction: Occupational therapy interventions, such as home visits, have been identified as being resource-intensive, but cost-effectiveness analyses are rarely, if ever, carried out. We sought to estimate the cost-effectiveness of occupational therapy home visits after stroke, as part of a feasibility study, and to demonstrate the value and methods of economic evaluation. Method: We completed a cost-effectiveness analysis of pre-discharge occupational therapy home visits after stroke compared with a hospital-based interview, carried out alongside a feasibility randomized controlled trial. Our primary outcome was quality-adjusted life years. Full cost and outcome data were available for 65 trial participants. Results: We found that the mean total cost of a home visit was £183, compared with £75 for a hospital interview. Home visits are shown to be slightly more effective, resulting in a cost per quality-adjusted life year of just over £20,000. Conclusion: Our analysis is the only economic evaluation of this intervention to date. Home visits are shown to be more expensive and more effective than a hospital-based interview, but our results are subject to a high level of uncertainty and should be treated as such. Further economic evaluations in this field are encouraged

Health state utility values for diabetic retinopathy: protocol for a systematic review and meta-analysis

Background People with diabetic retinopathy tend to have lower levels of health-related quality of life than individuals with no retinopathy. Strategies for screening and treatment have been shown to be cost-effective. In order to reduce the bias in cost-effectiveness estimates, systematic reviews of health state utility values (HSUVs) are crucial for health technology assessment and the development of decision analytic models. A review and synthesis of HSUVs for the different stages of disease progression in diabetic retinopathy has not previously been conducted. Methods/Design We will conduct a systematic review of the available literature that reports HSUVs for people with diabetic retinopathy, in correspondence with current stage of disease progression and/or visual acuity. We will search Medline, EMBASE, Web of Science, Cost-Effectiveness Analysis Registry, Centre for Reviews and Dissemination Database, and EconLit to identify relevant English-language articles. Data will subsequently be synthesized using linear mixed effects modeling meta-regression. Additionally, reported disease severity classifications will be mapped to a four-level grading scale for diabetic retinopathy. Discussion The systematic review and meta-analysis will provide important evidence for future model-based economic evaluations of technologies for diabetic retinopathy. The meta-regression will enable the estimation of utility values at different disease stages for patients with particular characteristics and will also highlight where the design of the study and HSUV instrument have influenced the reported utility values. We believe this protocol to be the first of its kind to be published

Cost implications of treatment non-completion in a forensic personality disorder service

Background A high proportion of individuals admitted to specialist secure hospital services for treatment of personality disorder do not complete treatment. Non-completion has been associated with poorer treatment outcomes and increased rates of recidivism and hospital readmission, when compared with individuals who do complete treatment or who do not receive treatment at all. Aims In this study, we sought to determine the economic consequences of non-completion of treatment, using case study data from a secure hospital sample. Both health and criminal justice service perspectives were taken into account. Methods Data were collected from a medium secure hospital personality disorder unit. A probabilistic decision-analytic model was constructed, using a Markov cohort simulation with 10,000 iterations. The expected cost differential between those who do and those who do not complete treatment was estimated, as was the probability of a cost differential over a 10-year post-admission time horizon. Results On average, in the first 10 years following admission, those who do not complete treatment go on to incur £52,000 more in costs to the National Health Service and criminal justice system than those who complete treatment. The model estimates that the probability that non-completers incur greater costs than completers is 78%. Conclusion It is possible that an improvement in treatment completion rates in secure hospital personality disorder units would lead to some cost savings. This might be achievable through better selection into treatment or improved strategies for engagement and retention. Our study highlights a financial cost to society of individuals discharged from secure hospital care when incompletely treated. We suggest that it could, therefore, be useful for secure hospitals to introduce routine monitoring of treatment completion

Do patients registered with CAM-trained GPs really use fewer health care resources and live longer? A response to Kooreman and Baars. Eur J Health Econ (2012). 13:469–776

Comment on Kooreman, P., Baars, E.W.: Patients whose GP knows complementary medicine tend to have lower costs and live longer. Eur. J. Health Econ.13(6), 769–776 (2012). doi:10.​1007/​s10198-011-0330-

Model registration: a call to action

Evidence regarding the effectiveness of health technologies can be distorted via numerous mechanisms, including publication bias, methodological errors, over- interpretation of findings and fraud. In recent years, popular science writers have brought these issues to the fore, resulting in popular movements to improve the credibility of science. One particularly effective campaign has been that of the AllTrials movement, which focuses on the pre-registration and reporting of all clinical trials [1]. Many of the concerns that led to this campaign can be observed in the context of decision modelling.In 2010, researchers called for the creation of a collaborative organisation to oversee a registry of decision models [2]. The concept was not realised. In recent years, the landscape of academic publishing and collaboration has changed dramatically. In this editorial, we restate the call for a model registry and recommend actionable steps for its introduction

Clinical characteristics of persistent frequent attenders in primary care: case–control study

Background. Most frequent attendance in primary care is temporary, but persistent frequent attendance is expensive and may be suitable for psychological intervention. To plan appropriate intervention and service delivery, there is a need for research involving standardized psychiatric interviews with assessment of physical health and health status. Objective. To compare the mental and physical health characteristics and health status of persistent frequent attenders (FAs) in primary care, currently and over the preceding 2 years, with normal attenders (NAs) matched by age, gender and general practice. Methods. Case–control study of 71 FAs (30 or more GP or practice nurse consultations in 2 years) and 71 NAs, drawn from five primary care practices, employing standardized psychiatric interview, quality of life, health anxiety and primary care electronic record review over the preceding 2 years. Results. Compared to NAs, FAs were more likely to report a lower quality of life (P < 0.001), be unmarried (P = 0.03) and have no educational qualifications (P = 0.009) but did not differ in employment status. FAs experienced greater health anxiety (P < 0.001), morbid obesity (P = 0.02), pain (P < 0.001) and long-term pathological and ill-defined physical conditions (P < 0.001). FAs had more depression including dysthymia, anxiety and somatoform disorders (all P < 0.001). Conclusions. Persistent frequent attendance in primary care was associated with poor quality of life and high clinical complexity characterized by diverse and often persistent physical and mental multimorbidity. A brokerage model with GPs working in close liaison with skilled psychological therapists is required to manage such persistent complexity

Occupational therapy predischarge home visits for patients with a stroke (HOVIS): results of a feasibility randomized controlled trial

Objective: To assess the feasibility of conducting a randomized controlled trial of occupational therapy predischarge home visits for people after stroke. Design: Randomized controlled trial and cohort study. We randomized eligible patients for whom there was clinical uncertainty about the need to conduct a home visit to a randomized controlled trial; patients for whom a visit was judged ‘essential’ were enrolled into a cohort study. Setting: Stroke rehabilitation unit of teaching hospital. Participants: One hundred and twenty-six participants hospitalized following recent stroke. Interventions: Predischarge home visit or structured, hospital-based interview. Main outcome measures: The primary objective was to collect information on the feasibility of a randomized controlled trial, including eligibility, control intervention and outcome assessments. The primary outcome measure was the Nottingham Extended Activities of Daily Living Scale at one month after discharge from hospital. Secondary outcomes included mood, quality of life and costs at one week and one month following discharge. Results: Ninety-three people were allocated to the randomized controlled trial; 47 were randomized to intervention and 46 to control. Thirty-three were enrolled into the cohort study. More people were allocated to the randomized controlled trial as the study progressed. One hundred and thirteen people (90%) received the proposed intervention, although there was a need for stricter protocol adherence. Follow-up was good: at one month 114 (90%) were assessed. There were no significant differences between the groups in the randomized controlled trial for the primary outcome measure at one month. The average cost of a home visit was £208. Conclusion: A trial is feasible and warranted given the resource implications of predischarge occupational therapy home visits