The NightLife study - the clinical and cost-effectiveness of thrice-weekly, extended, in-centre nocturnal haemodialysis versus daytime haemodialysis using a mixed methods approach: study protocol for a randomised controlled trial.

BACKGROUND: In-centre nocturnal haemodialysis (INHD) offers extended-hours haemodialysis, 6 to 8 h thrice-weekly overnight, with the support of dialysis specialist nurses. There is increasing observational data demonstrating potential benefits of INHD on health-related quality of life (HRQoL). There is a lack of randomised controlled trial (RCT) data to confirm these benefits and assess safety. METHODS: The NightLife study is a pragmatic, two-arm, multicentre RCT comparing the impact of 6 months INHD to conventional haemodialysis (thrice-weekly daytime in-centre haemodialysis, 3.5-5 h per session). The primary outcome is the total score from the Kidney Disease Quality of Life tool at 6 months. Secondary outcomes include sleep and cognitive function, measures of safety, adherence to dialysis and impact on clinical parameters. There is an embedded Process Evaluation to assess implementation, health economic modelling and a QuinteT Recruitment Intervention to understand factors that influence recruitment and retention. Adults (≥ 18 years old) who have been established on haemodialysis for > 3 months are eligible to participate. DISCUSSION: There are 68,000 adults in the UK that need kidney replacement therapy (KRT), with in-centre haemodialysis the treatment modality for over a third of cases. HRQoL is an independent predictor of hospitalisation and mortality in individuals on maintenance dialysis. Haemodialysis is associated with poor HRQoL in comparison to the general population. INHD has the potential to improve HRQoL. Vigorous RCT evidence of effectiveness is lacking. The NightLife study is an essential step in the understanding of dialysis therapies and will guide patient-centred decisions regarding KRT in the future. TRIAL REGISTRATION: Trial registration number: ISRCTN87042063. Registered: 14/07/2020.

The economic burden of antibiotic resistance: A systematic review and meta-analysis.

INTRODUCTION: Antibiotic resistance (ABR) has substantial global public health concerns. This systematic review aimed to synthesise recent evidence estimating the economic burden of ABR, characterised by study perspectives, healthcare settings, study design, and income of the countries. METHODS: This systematic review included peer-reviewed articles from PubMed, Medline, and Scopus databases, and grey literature on the topic of the economic burden of ABR, published between January 2016 and December 2021. The study was reported in line with 'Preferred Reporting Items for Systematic Review and Meta-Analysis' (PRISMA). Two reviewers independently screened papers for inclusion first by title, then abstract, and then the full text. Study quality was assessed using appropriate quality assessment tools. Narrative synthesis and meta-analyses of the included studies were conducted. RESULTS: A total of 29 studies were included in this review. Out of these studies, 69% (20/29) were conducted in high-income economies and the remainder were conducted in upper-and-middle income economies. Most of the studies were conducted from a healthcare or hospital perspective (89.6%, 26/29) and 44.8% (13/29) studies were conducted in tertiary care settings. The available evidence indicates that the attributable cost of resistant infection ranges from -US$2,371.4 to +US$29,289.1 (adjusted for 2020 price) per patient episode; the mean excess length of stay (LoS) is 7.4 days (95% CI: 3.4-11.4), the odds ratios of mortality for resistant infection is 1.844 (95% CI: 1.187-2.865) and readmission is 1.492 (95% CI: 1.231-1.807). CONCLUSION: Recent publications show that the burden of ABR is substantial. There is still a lack of studies on the economic burden of ABR from low-income economies, and lower-middle-income economies, from a societal perspective, and in relation to primary care. The findings of this review may be of value to researchers, policymakers, clinicians, and those who are working in the field of ABR and health promotion. SYSTEMATIC REVIEW REGISTRATION: CRD42020193886.

Meta-analysis of dichotomous and ordinal tests with an imperfect gold standard.

Standard methods for the meta-analysis of medical tests, without assuming a gold standard, are limited to dichotomous data. Multivariate probit models are used to analyse correlated dichotomous data, and can be extended to model ordinal data. Within the context of an imperfect gold standard, they have previously been used for the analysis of dichotomous and ordinal test data from a single study, and for the meta-analysis of dichotomous tests. However, they have not previously been used for the meta-analysis of ordinal tests. In this article, we developed a Bayesian multivariate probit latent class model for the simultaneous meta-analysis of ordinal and dichotomous tests without assuming a gold standard, which also allows one to obtain summary estimates of joint test accuracy. We fitted the models using the software Stan, which uses a state-of-the-art Hamiltonian Monte Carlo algorithm, and we applied the models to a dataset in which studies evaluated the accuracy of tests, and test combinations, for deep vein thrombosis. We demonstrate the issues with dichotomising ordinal test accuracy data in the presence of an imperfect gold standard, before applying and comparing several variations of our proposed model which do not require the data to be dichotomised. The models proposed will allow researchers to more appropriately meta-analyse ordinal and dichotomous tests without a gold standard, potentially leading to less biased estimates of test accuracy. This may lead to a better understanding of which tests, and test combinations, should be used for any given medical condition.

A Cost-Effective Analysis of the CYCLE-HD Randomized Controlled Trial.

INTRODUCTION: No formal cost-effectiveness analysis has been performed for programs of cycling exercise during dialysis (intradialytic cycling [IDC]). The objective of this analysis is to determine the effect of a 6-month program of IDC on health care costs. METHODS: This is a retrospective formal cost-effectiveness analysis of adult participants with end-stage kidney disease undertaking in-center maintenance hemodialysis enrolled in the CYCLE-HD trial. Data on hospital utilization, primary care consultations, and prescribed medications were extracted from medical records for the 6 months before, during, and after a 6-month program of thrice-weekly IDC. The cost-effectiveness analysis was conducted from a health care service perspective and included the cost of implementing the IDC intervention. The base-case analyses included a 6-month "within trial" analysis and a 12-month "within and posttrial" analysis considering health care utilization and quality of life (QoL) outcomes. RESULTS: Data from the base-case within trial analysis, based on 109 participants (n = 56 control subjects and n = 53 IDC subjects) showed a reduction in health care utilization costs between groups, favoring the IDC group, and a 73% chance of IDC being cost-effective compared with control subjects at a willingness to pay of £20,000 and £30,000 per quality-adjusted life year (QALY) gained. When QoL data points were extrapolated forward to 12 months, the probability of IDC being cost-effective was 93% and 94% at £20,000 and £30,000 per QALY gained. Sensitivity analysis broadly confirms these findings. CONCLUSION: A 6-month program of IDC is cost-effective and the implementation of these programs nationally should be a priority.

Patient-initiated follow-up for low-risk endometrial cancer: a cost-analysis evaluation.

OBJECTIVE: Risk stratification has resulted in patient-initiated follow-up being introduced for low-risk endometrial cancer in place of routine hospital follow-up. The financial benefit to the patient and the healthcare economy of patient-initiated follow-up, as compared with hospital follow-up, has yet to be explored. In this study, we explored the potential impact for both the healthcare economy and patients of patient-initiated follow-up. METHODS: Women diagnosed with low-risk endometrial cancer enrolled on a patient-initiated follow-up scheme between November 2014 and September 2018 were included. Data on the number of telephone calls to the nurse specialists and clinic appointments attended were collected prospectively. The number of clinic appointments that would have taken place if the patient had continued on hospital follow-up, rather than starting on patient-initiated follow-up, was calculated and costs determined using standard National Health Service (NHS) reference costs. The time/distance traveled by patients from their home address to the hospital clinic was calculated and used to determine patient-related costs. RESULTS: A total of 187 patients with a median of 37 (range 2-62) months follow-up after primary surgery were enrolled on the scheme. In total, the cohort were scheduled to attend 1673 appointments with hospital follow-up, whereas they only attended 69 clinic appointments and made 107 telephone contacts with patient-initiated follow-up. There was a 93.5% reduction in costs from a projected £194 068.00 for hospital follow-up to £12 676.33 for patient-initiated follow-up. The mean patient-related costs were reduced by 95.6% with patient-initiated follow-up. The total mileage traveled by patients for hospital follow-up was 30 891.4 miles, which was associated with a mean traveling time per patient of 7.41 hours and clinic/waiting time of 7.5 hours compared with 1165.8 miles and 0.46 hours and 0.5 hours, respectively, for patient-initiated follow-up. CONCLUSION: The introduction of a patient self-management follow-up scheme for low-risk endometrial cancer was associated with financial/time saving to both the patient and the healthcare economy as compared with hospital follow-up.

Uptake of methodological advances for synthesis of continuous and time-to-event outcomes would maximize use of the evidence base.

OBJECTIVE: The objective of the study is to establish how often continuous and time-to-event outcomes are synthesized in health technology assessment (HTA), the statistical methods and software used in their analysis and how often evidence synthesis informs decision models. STUDY DESIGN AND SETTING: This is a review of National Institute of Health Research HTA reports, National Institute for Health and Care Excellence (NICE) technology appraisals, and NICE guidelines reporting quantitative meta-analysis or network meta-analysis of at least one continuous or time-to-event outcome published from April 01, 2018 to March 31, 2019. RESULTS: We identified 47 eligible articles. At least one continuous or time-to-event outcome was synthesized in 51% and 55% of articles, respectively. Evidence synthesis results informed decision models in two-thirds of articles. The review and expert knowledge identified five areas where methodology is available for improving the synthesis of continuous and time-to-event outcomes: i) outcomes reported on multiple scales, ii) reporting of multiple related outcomes, iii) appropriateness of the additive scale, iv) reporting of multiple time points, and v) nonproportional hazards. We identified three anticipated barriers to the uptake and implementation of these methods: i) statistical expertise, ii) software, and iii) reporting of trials. CONCLUSION: Continuous and time-to-event outcomes are routinely reported in HTA. However, increased uptake of methodological advances could maximize the evidence base used to inform the decision making process.

Network meta-analysis of diagnostic test accuracy studies identifies and ranks the optimal diagnostic tests and thresholds for health care policy and decision-making.

OBJECTIVES: Network meta-analyses (NMA) have extensively been used to compare the effectiveness of multiple interventions for health care policy and decision-making. However, methods for evaluating the performance of multiple diagnostic tests are less established. In a decision-making context, we are often interested in comparing and ranking the performance of multiple diagnostic tests, at varying levels of test thresholds, in one simultaneous analysis. STUDY DESIGN AND SETTING: Motivated by an example of cognitive impairment diagnosis following stroke, we synthesized data from 13 studies assessing the efficiency of two diagnostic tests: Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA), at two test thresholds: MMSE <25/30 and <27/30, and MoCA <22/30 and <26/30. Using Markov chain Monte Carlo (MCMC) methods, we fitted a bivariate network meta-analysis model incorporating constraints on increasing test threshold, and accounting for the correlations between multiple test accuracy measures from the same study. RESULTS: We developed and successfully fitted a model comparing multiple tests/threshold combinations while imposing threshold constraints. Using this model, we found that MoCA at threshold <26/30 appeared to have the best true positive rate, whereas MMSE at threshold <25/30 appeared to have the best true negative rate. CONCLUSION: The combined analysis of multiple tests at multiple thresholds allowed for more rigorous comparisons between competing diagnostics tests for decision making.

A decision analytic model to investigate the cost-effectiveness of poisoning prevention practices in households with young children.

BACKGROUND: Systematic reviews and a network meta-analysis show home safety education with or without the provision of safety equipment is effective in promoting poison prevention behaviours in households with children. This paper compares the cost-effectiveness of home safety interventions to promote poison prevention practices. METHODS: A probabilistic decision-analytic model simulates healthcare costs and benefits for a hypothetical cohort of under 5 year olds. The model compares the cost-effectiveness of home safety education, home safety inspections, provision of free or low cost safety equipment and fitting of equipment. Analyses are conducted from a UK National Health Service and Personal Social Services perspective and expressed in 2012 prices. RESULTS: Education without safety inspection, provision or fitting of equipment was the most cost-effective strategy for promoting safe storage of medicines with an incremental cost-effectiveness ratio of £2888 (95 % credible interval (CrI) £1990-£5774) per poison case avoided or £41,330 (95%CrI £20,007-£91,534) per QALY gained compared with usual care. Compared to usual care, home safety interventions were not cost-effective in promoting safe storage of other household products. CONCLUSION: Education offers better value for money than more intensive but expensive strategies for preventing medicinal poisonings, but is only likely to be cost-effective at £30,000 per QALY gained for families in disadvantaged areas and for those with more than one child. There was considerable uncertainty in cost-effectiveness estimates due to paucity of evidence on model parameters. Policy makers should consider both costs and effectiveness of competing interventions to ensure efficient use of resources.

A cost-effectiveness modelling study of strategies to reduce risk of infection following primary hip replacement based on a systematic review.

BACKGROUND: A deep infection of the surgical site is reported in 0.7% of all cases of total hip arthroplasty (THA). This often leads to revision surgery that is invasive, painful and costly. A range of strategies is employed in NHS hospitals to reduce risk, yet no economic analysis has been undertaken to compare the value for money of competing prevention strategies. OBJECTIVES: To compare the costs and health benefits of strategies that reduce the risk of deep infection following THA in NHS hospitals. To make recommendations to decision-makers about the cost-effectiveness of the alternatives. DESIGN: The study comprised a systematic review and cost-effectiveness decision analysis. SETTING: 77,321 patients who had a primary hip arthroplasty in NHS hospitals in 2012. INTERVENTIONS: Nine different treatment strategies including antibiotic prophylaxis, antibiotic-impregnated cement and ventilation systems used in the operating theatre. MAIN OUTCOME MEASURES: Change in the number of deep infections, change in the total costs and change in the total health benefits in quality-adjusted life-years (QALYs). DATA SOURCES: Literature searches using MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature and the Cochrane Central Register of Controlled Trials were undertaken to cover the period 1966-2012 to identify infection prevention strategies. Relevant journals, conference proceedings and bibliographies of retrieved papers were hand-searched. Orthopaedic surgeons and infection prevention experts were also consulted. REVIEW METHODS: English-language papers only. The selection of evidence was by two independent reviewers. Studies were included if they were interventions that reported THA-related deep surgical site infection (SSI) as an outcome. Mixed-treatment comparisons were made to produce estimates of the relative effects of competing infection control strategies. RESULTS: Twelve studies, six randomised controlled trials and six observational studies, involving 123,788 total hip replacements (THRs) and nine infection control strategies, were identified. The quality of the evidence was judged against four categories developed by the National Institute for Health and Care Excellence Methods for Development of NICE Public Health Guidance ( http://publications.nice.org.uk/methods-for-the-development-of-nice-public-health-guidance-third-edition-pmg4 ), accessed March 2012. All evidence was found to fit the two highest categories of 1 and 2. Nine competing infection control interventions [treatments (Ts) 1-9] were used in a cohort simulation model of 77,321 patients who had a primary THR in 2012. Predictions were made for cases of deep infection and total costs, and QALY outcomes. Compared with a baseline of T1 (no systemic antibiotics, plain cement and conventional ventilation) all other treatment strategies reduced risk. T6 was the most effective (systemic antibiotics, antibiotic-impregnated cement and conventional ventilation) and prevented a further 1481 cases of deep infection, and led to the largest annual cost savings and the greatest gains to QALYs. The additional uses of laminar airflow and body exhaust suits indicate higher costs and worse health outcomes. CONCLUSIONS: T6 is an optimal strategy for reducing the risk of SSI following THA. The other strategies that are commonly used among NHS hospitals lead to higher cost and worse QALY outcomes. Policy-makers, therefore, have an opportunity to save resources and improve health outcomes. The effects of laminar air flow and body exhaust suits might be further studied if policy-makers are to consider disinvesting in these technologies. LIMITATIONS: A wide range of evidence sources was synthesised and there is large uncertainty in the conclusions. FUNDING: The National Institute for Health Research Health Technology Assessment programme and the Queensland Health Quality Improvement and Enhancement Programme (grant number 2008001769).

The effectiveness of different interventions to promote poison prevention behaviours in households with children: a network meta-analysis.

BACKGROUND: There is evidence from 2 previous meta-analyses that interventions to promote poison prevention behaviours are effective in increasing a range of poison prevention practices in households with children. The published meta-analyses compared any intervention against a "usual care or no intervention" which potentially limits the usefulness of the analysis to decision makers. We aim to use network meta-analysis to simultaneously evaluate the effectiveness of different interventions to increase prevalence of safe storage of i) Medicines only, ii) Other household products only, iii) Poisons (both medicines and non-medicines), iv) Poisonous plants; and v) Possession of poison control centre (PCC) telephone number in households with children. METHODS: Data on the effectiveness of poison prevention interventions was extracted from primary studies identified in 2 newly-undertaken systematic reviews. Effect estimates were pooled across studies using a random effects network meta-analysis model. RESULTS: 28 of the 47 primary studies identified were included in the analysis. Compared to usual care intervention, the intervention with education and low cost/free equipment elements was most effective in promoting safe storage of medicines (odds ratio 2.51, 95% credible interval 1.01 to 6.00) while interventions with education, low cost/free equipment, home safety inspection and fitting components were most effective in promoting safe storage of other household products (2.52, 1.12 to 7.13), safe storage of poisons (11.10, 1.60 to 141.50) and possession of PCC number (38.82, 2.19 to 687.10). No one intervention package was more effective than the others in promoting safe storage of poisonous plants. CONCLUSION: The most effective interventions varied by poison prevention practice, but education alone was not the most effective intervention for any poison prevention practice. Commissioners and providers of poison prevention interventions should tailor the interventions they commission or provide to the poison prevention practices they wish to promote. HIGHLIGHTS: Network meta-analysis is useful for comparing multiple injury-prevention interventions. More intensive poison prevention interventions were more effective than education alone. Education and low cost/free equipment was most effective in promoting safe storage of medicines. Education, low cost/free equipment, home safety inspection and fitting was most effective in promoting safe storage of household products and poisons. Education, low cost/free equipment and home inspection were most effective in promoting possession of a poison control centre number. None of the intervention packages was more effective than the others in promoting safe storage of poisonous plants.

Direct health costs of inflammatory polyarthritis 10 years after disease onset: results from the Norfolk Arthritis Register.

OBJECTIVES: To explore the change in direct medical costs associated with inflammatory polyarthritis (IP) 10 to 15 years after its onset. METHODS: Patients from the Norfolk Arthritis Register who had previously participated in a health economic study in 1999 were traced 10 years later and invited to participate in a further prospective questionnaire-based study. The study was designed to identify direct medical costs and changes in health status over a 6-month period using previously validated questionnaires as the primary source of data. RESULTS: A representative sample of 101 patients with IP from the 1999 cohort provided complete data over the 6-month period. The mean disease duration was 14 years (SD 2.1, median 13.6, interquartile range 12.6-15.4). The mean direct medical cost per patient over the 6-month period was £1496 for IP (inflated for 2013 prices). This compared with £582 (95% CI £355-£964) inflated to 2013 prices per patient with IP 10 years earlier in their disease. The increased cost was largely associated with the use of biologics in the rheumatoid arthritis subgroup of patients (51% of total costs incurred). Other direct cost components included primary care costs (11%), hospital outpatient (19%), day care (12%), and inpatient stay (4%). CONCLUSION: The direct healthcare costs associated with IP have more than doubled with increasing disease duration, largely as a result of the use of biologics. The results showed a shift in the direct health costs from inpatient to outpatient service use.

Network meta-analysis to evaluate the effectiveness of interventions to prevent falls in children under age 5 years.

BACKGROUND: This study aimed to simultaneously evaluate the effectiveness of a range of interventions to increase the possession of safety equipment or behaviours to prevent falls in children under 5 years of age in the home. METHODS: A recently published systematic review identified studies to be included in a network meta-analysis; an extension of pairwise meta-analysis that enables comparison of all evaluated interventions simultaneously, including comparisons not directly compared in individual studies. RESULTS: 29 primary studies were identified, of which 16 were included in at least 1 of 4 network meta-analyses. For increasing possession of a fitted stair gate, the most intensive intervention (including education, low cost/free home safety equipment, home safety inspection and fitting) was the most likely to be the most effective, with an OR versus usual care of 7.80 (95% CrI 3.08 to 21.3). For reducing possession or use of a baby walker: education only was most likely to be most effective, with an OR versus usual care of 0.48 (95% CrI 0.31 to 0.84). Little difference was found between interventions for possession of window locks (most intensive intervention versus usual care OR=1.56 (95% CrI 0.02 to 89.8)) and for not leaving a child alone on a high surface (education vs usual care OR=0.89 (95% CrI 0.10 to 9.67)). There was insufficient evidence for network meta-analysis for possession and use of bath mats. CONCLUSIONS: These results will inform healthcare providers of the most effective components of interventions and can be used in cost-effectiveness analyses.

Network meta-analysis of multiple outcome measures accounting for borrowing of information across outcomes.

BACKGROUND: Network meta-analysis (NMA) enables simultaneous comparison of multiple treatments while preserving randomisation. When summarising evidence to inform an economic evaluation, it is important that the analysis accurately reflects the dependency structure within the data, as correlations between outcomes may have implication for estimating the net benefit associated with treatment. A multivariate NMA offers a framework for evaluating multiple treatments across multiple outcome measures while accounting for the correlation structure between outcomes. METHODS: The standard NMA model is extended to multiple outcome settings in two stages. In the first stage, information is borrowed across outcomes as well across studies through modelling the within-study and between-study correlation structure. In the second stage, we make use of the additional assumption that intervention effects are exchangeable between outcomes to predict effect estimates for all outcomes, including effect estimates on outcomes where evidence is either sparse or the treatment had not been considered by any one of the studies included in the analysis. We apply the methods to binary outcome data from a systematic review evaluating the effectiveness of nine home safety interventions on uptake of three poisoning prevention practices (safe storage of medicines, safe storage of other household products, and possession of poison centre control telephone number) in households with children. Analyses are conducted in WinBUGS using Markov Chain Monte Carlo (MCMC) simulations. RESULTS: Univariate and the first stage multivariate models produced broadly similar point estimates of intervention effects but the uncertainty around the multivariate estimates varied depending on the prior distribution specified for the between-study covariance structure. The second stage multivariate analyses produced more precise effect estimates while enabling intervention effects to be predicted for all outcomes, including intervention effects on outcomes not directly considered by the studies included in the analysis. CONCLUSIONS: Accounting for the dependency between outcomes in a multivariate meta-analysis may or may not improve the precision of effect estimates from a network meta-analysis compared to analysing each outcome separately.

Cost-effectiveness of interventions for increasing the possession of functioning smoke alarms in households with pre-school children: a modelling study.

BACKGROUND: The UK has one of the highest rates for deaths from fire and flames in children aged 0-14 years compared to other high income countries. Evidence shows that smoke alarms can reduce the risk of fire-related injury but little exists on their cost-effectiveness. We aimed to compare the cost effectiveness of different interventions for the uptake of 'functioning' smoke alarms and consequently for the prevention of fire-related injuries in children in the UK. METHODS: We carried out a decision model-based probabilistic cost-effectiveness analysis. We used a hypothetical population of newborns and evaluated the impact of living in a household with or without a functioning smoke alarm during the first 5 years of their life on overall lifetime costs and quality of life from a public health perspective. We compared seven interventions, ranging from usual care to more complex interventions comprising of education, free/low cost equipment giveaway, equipment fitting and/or home safety inspection. RESULTS: Education and free/low cost equipment was the most cost-effective intervention with an estimated incremental cost-effectiveness ratio of £34,200 per QALY gained compared to usual care. This was reduced to approximately £4,500 per QALY gained when 1.8 children under the age of 5 were assumed per household. CONCLUSIONS: Assessing cost-effectiveness, as well as effectiveness, is important in a public sector system operating under a fixed budget restraint. As highlighted in this study, the more effective interventions (in this case the more complex interventions) may not necessarily be the ones considered the most cost-effective.

Use of Bayesian multivariate meta-analysis to estimate the HAQ for mapping onto the EQ-5D questionnaire in rheumatoid arthritis.

BACKGROUND: In health technology assessment, decisions about reimbursement for new health technologies are largely based on effectiveness estimates. Sometimes, however, the target effectiveness estimates are not readily available. This may be because many alternative instruments measuring these outcomes are being used (and not all always reported) or an extended follow-up time of clinical trials is needed to evaluate long-term end points, leading to the limited data on the target clinical outcome. In the areas of highest priority in health care, decisions are required to be made on a short time scale. Therefore, alternative clinical outcomes, including surrogate end points, are increasingly being considered for use in evidence synthesis as part of economic evaluation. OBJECTIVE: To illustrate the potential effect of reduced uncertainty around the clinical outcome on the utility when estimating it from a multivariate meta-analysis. METHODS: Bayesian multivariate meta-analysis has been used to synthesize data on correlated outcomes in rheumatoid arthritis and to incorporate external data in the model in the form of informative prior distributions. Estimates of Health Assessment Questionnaire were then mapped onto the health-related quality-of-life measure EuroQol five-dimensional questionnaire, and the effect was compared with mapping the Health Assessment Questionnaire obtained from the univariate approach. RESULTS: The use of multivariate meta-analysis can lead to reduced uncertainty around the effectiveness parameter and ultimately uncertainty around the utility. CONCLUSIONS: By allowing all the relevant data to be incorporated in estimating clinical effectiveness outcomes, multivariate meta-analysis can improve the estimation of health utilities estimated through mapping methods. While reduced uncertainty may have an effect on decisions based on economic evaluation of new health technologies, the use of short-term surrogate end points can allow for early decisions. More research is needed to determine the circumstances under which uncertainty is reduced.

Multicentre cluster randomised controlled trial evaluating implementation of a fire prevention Injury Prevention Briefing in children's centres: study protocol.

BACKGROUND: The UK has one of the highest fatality rates for deaths from fire-related injuries in children aged 0-14 years; these injuries have the steepest social gradient of all injuries in the UK. Children's centres provide children under five years old and their families with a range of services and information, including home safety, but their effectiveness in promoting injury prevention has yet to be evaluated. We developed a fire prevention intervention for use in children's centres comprising an Injury Prevention Briefing (IPB) which provides evidence on what works and best practice from those running injury prevention programmes, and a facilitation package to support implementation of the IPB. This protocol describes the design and methods of a trial evaluating the effectiveness and cost-effectiveness of the IPB and facilitation package in promoting fire prevention. METHODS/DESIGN: Pragmatic, multicentre cluster randomised controlled trial, with a nested qualitative study, in four study centres in England. Children's centres in the most disadvantaged areas will be eligible to participate and will be randomised to one of three treatment arms comprising: IPB with facilitation package; IPB with no facilitation package; usual care (control). The primary outcome measure will be the proportion of families who have a fire escape plan at follow-up. Eleven children's centres per arm are required to detect an absolute difference in the percentage of families with a fire escape plan of 20% in either of the two intervention arms compared with the control arm, with 80% power and a 5% significance level (2-sided), an intraclass correlation coefficient of 0.05 and assuming outcomes are assessed on 20 families per children's centre. Secondary outcomes include the assessment of the cost-effectiveness of the intervention, other fire safety behaviours and factors associated with degree of implementation of the IPB. DISCUSSION: This will be the first trial to develop and evaluate a fire prevention intervention for use in children's centres in the UK. Its findings will be generalisable to children's centres in the most disadvantaged areas of the UK and may also be generalisable to similar interventions to prevent other types of injury. TRIAL REGISTRATION: http://NCT01452191 (date of registration: 13/10/2011).

Presentational approaches used in the UK for reporting evidence synthesis using indirect and mixed treatment comparisons.

OBJECTIVES: To establish current guidance and practice in UK on presentation of indirect comparison and mixed treatment comparison analyses; to provide recommendations to improve indirect comparison/mixed treatment comparison reporting and to identify research priorities for improved presentation. METHODS: Existing institutional guidance for conducting indirect comparison/mixed treatment comparison alongside current practice in health technology assessment was reviewed. Reports published in UK by the Health Technology Assessment programme since 1997, which utilized indirect comparison/mixed treatment comparison methods, were reviewed with respect to the presentation of study data, statistical models and results. Recommendations for presentation were developed. RESULTS: Guidance exists that provide the details necessary to conduct a successful indirect comparison/mixed treatment comparison analysis but recommendations on presentation are limited. Of 205 health technology assessment reports that contained evidence synthesis for effectiveness, 19 used indirect comparison/mixed treatment comparison methods. These reports utilized numerous presentational formats from which the following key components were identified: network table/diagram for presenting data; model description to allow reproducibility; and tables, forest plots, matrix tables and summary forest plots for presenting a range of results. Recommendations were developed to ensure that reporting is explicit, transparent and reproducible. Approaches most understandable by non-technical decision makers, and areas where future research is required, are outlined. CONCLUSIONS: There is no standard presentational style used in UK for reporting indirect comparison/mixed treatment comparison, and the use of graphical tools is limited. Standardization of reporting and innovation in graphical representation of indirect comparison/mixed treatment comparison results is required.

Use of implicit and explicit bayesian methods in health technology assessment.

OBJECTIVES: The aim of this study was to examine the use of implicit and explicit Bayesian methods in health technology assessments and to identify whether this has changed over time. METHODS: A review of all health technology assessment (HTA) reports of secondary research published by the UK National Institute of Health Research (NIHR) between 1997 and 2011. Data were extracted on the use and implementation of Bayesian methods, whether defined as such by the original authors (i.e., explicit) or not (i.e., implicit). RESULTS: A total of 155 of 375 (41 percent) NIHR HTA reports, identified as relevant to this review, contained a Bayesian analysis. Of these, 128 (83 percent) contained an implicit Bayesian analysis, 3 (2 percent) an explicit Bayesian analysis and 24 (15 percent) both implicit and explicit Bayesian analyses. Of the twenty-seven reports that explicitly used Bayes theorem, only six included prior information in the form of (informative) prior distributions. Over time, the percentage of HTA reports that used Bayesian (implicit and/or explicit) methods increased from 0 percent in 1997 to nearly 80 percent in 2011. CONCLUSIONS: This review has shown that there has been an increase in the use of Bayesian methods in HTA, which is likely to be a result of the increase in freely available resources to implement the approach. Areas where Bayesian methods have the potential to advance healthcare evaluations in the future are considered in the discussion.

Evaluating the cost-effectiveness of diagnostic tests in combination: is it important to allow for performance dependency?

OBJECTIVES: To investigate the importance of accounting for potential performance dependency when evaluating the cost-effectiveness of two diagnostic tests used in combination. METHODS: Two meta-analysis models were fitted to estimate the diagnostic accuracy of Wells score and Ddimer in combination. The first model assumes that the two tests perform independently of one another; thus, two separate meta-analyses were fitted to the Ddimer and Wells score data and then combined. The second model allows for any performance dependency of the two tests by incorporating published data on the accuracy of Ddimer stratified by Wells score, as well as studies of Ddimer alone and Wells score alone. The results from the two meta-analysis models were input into a decision model to assess the impact that assumptions regarding performance dependency have on the overall cost-effectiveness of the tests. RESULTS: The results highlight the importance of accounting for potential performance dependency when evaluating the cost-effectiveness of diagnostic tests used in combination. In our example, assuming the diagnostic performance of the two tests to be independent resulted in the strategy "Wells score moderate/high risk treated for DVT and Wells score low risk tested further with Ddimer" being identified as the most cost-effective at the £20,000 willingness-to-pay threshold (probability cost-effective 0.8). However, when performance dependency is modeled, the most cost-effective strategies were "Ddimer alone" and "Wells score low/moderate risk discharged and Wells score high risk further tested with Ddimer" (probability cost-effective 0.4). CONCLUSIONS: When evaluating the effectiveness and cost-effectiveness of diagnostic tests used in combination, failure to account for diagnostic performance dependency may lead to erroneous results and nonoptimal decision making.