Assessment of the impact of social deprivation, distance to hospital and time to diagnosis on survival in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive condition associated with a variable prognosis. The relationship between socioeconomic status or distance travelled to respiratory clinics and prognosis is unclear. RESEARCH QUESTION: To determine whether socioeconomic status, distance to hospital and time to referral affects survival in patients with IPF. STUDY DESIGN AND METHODS: In this retrospective cohort study, we used data collected from the British Thoracic Society Interstitial Lung Diseases Registry, between 2013 and 2021 (n = 2359) and calculated the quintile of Index of Multiple Deprivation 2019 score, time from initial symptoms to hospital attendance and distance as the linear distance between hospital and home post codes. Survival was assessed using Cox proportional hazards models. RESULTS: There was a significant association between increasing quintile of deprivation and duration of symptoms prior to hospital presentation, Gender Age Physiology (GAP) index and receipt of supplemental oxygen and antifibrotic therapies at presentation. The most deprived patients had worse overall survival compared to least deprived after adjusting for smoking status, GAP index, distance to hospital and time to referral (HR = 1.39 [1.11, 1.73]; p = 0.003). Patients living furthest from a respiratory clinic also had worse survival compared to those living closest (HR = 1.29 [1.01, 1.64]; p = 0.041). INTERPRETATION: The most deprived patients with IPF have more severe disease at presentation and worse outcomes. Living far from hospital was also associated with poor outcomes. This suggests inequalities in access to healthcare and requires consideration in delivering effective and equitable care to patients with IPF.

Hospital-based caregiver intervention for people following hip fracture surgery (HIP HELPER): multicentre randomised controlled feasibility trial with embedded qualitative study in England.

OBJECTIVES: To assess the feasibility of conducting a pragmatic, multicentre randomised controlled trial (RCT) to test the clinical and cost-effectiveness of an informal caregiver training programme to support the recovery of people following hip fracture surgery. DESIGN: Two-arm, multicentre, pragmatic, open, feasibility RCT with embedded qualitative study. SETTING: National Health Service (NHS) providers in five English hospitals. PARTICIPANTS: Community-dwelling adults, aged 60 years and over, who undergo hip fracture surgery and their informal caregivers. INTERVENTION: Usual care: usual NHS care. EXPERIMENTAL: usual NHS care plus a caregiver-patient dyad training programme (HIP HELPER). This programme comprised three, 1 hour, one-to-one training sessions for a patient and caregiver, delivered by a nurse, physiotherapist or occupational therapist in the hospital setting predischarge. After discharge, patients and caregivers were supported through three telephone coaching sessions. RANDOMISATION AND BLINDING: Central randomisation was computer generated (1:1), stratified by hospital and level of patient cognitive impairment. There was no blinding. MAIN OUTCOME MEASURES: Data collected at baseline and 4 months post randomisation included: screening logs, intervention logs, fidelity checklists, acceptability data and clinical outcomes. Interviews were conducted with a subset of participants and health professionals. RESULTS: 102 participants were enrolled (51 patients; 51 caregivers). Thirty-nine per cent (515/1311) of patients screened were eligible. Eleven per cent (56/515) of eligible patients consented to be randomised. Forty-eight per cent (12/25) of the intervention group reached compliance to their allocated intervention. There was no evidence of treatment contamination. Qualitative data demonstrated the trial and HIP HELPER programme was acceptable. CONCLUSIONS: The HIP HELPER programme was acceptable to patient-caregiver dyads and health professionals. The COVID-19 pandemic impacting on site's ability to deliver the research. Modifications are necessary to the design for a viable definitive RCT. TRIAL REGISTRATION NUMBER: ISRCTN13270387.

Informal caregiver training for people with chronic pain in musculoskeletal services (JOINT SUPPORT): protocol for a feasibility randomised controlled trial.

INTRODUCTION: Chronic musculoskeletal (bone, joint or muscle) pain is disabling. People with it frequently have difficulties in managing everyday activities. Individuals may rely on family members or friends to support them. These people are known as informal caregivers. No interventions have previously addressed the health needs of people with chronic musculoskeletal pain and their caregivers. In response, the JOINT SUPPORT programme was developed. In this study, we will assess the feasibility and acceptability of conducting a pragmatic, multicentre, randomised controlled trial (RCT) to test the clinical and cost-effectiveness of the JOINT SUPPORT programme to support these individuals. METHODS AND ANALYSIS: This will be a mixed-methods feasibility RCT. We will recruit 80 patients with chronic musculoskeletal pain with their informal caregivers. Patients will be randomised to usual National Health Service (NHS) care OR usual NHS care plus a caregiver-patient dyad training programme (JOINT SUPPORT). This programme comprises of five, 1-hour, group-based sessions for patients and caregivers, delivered by trained physiotherapists or occupational therapists. It includes developing skills in: understanding pain, pacing, graded activity, fear avoidance and goal-setting, understanding benefits of physical activity and skills in medication management. This will be re-enforced with a workbook. After the group-based sessions, patients and caregivers will be supported through three telephone sessions with a therapist. Data collected at baseline and 3 months will include: screening logs, intervention logs, fidelity checklists and clinical outcomes on quality of life, physical and emotional outcomes, adverse events and resource use. Qualitative research with 24 patient-caregiver dyads and 12 healthcare professionals will explore the acceptability of trial processes. Stop-go criteria will inform the progression to a full trial. ETHICS AND DISSEMINATION: Ethical approval was obtained on 22 February 2022 (National Research Ethics Committee Number: 22/NW/0015). Results will be reported at conferences, peer-review publications and across social media channels. TRIAL REGISTRATION NUMBER: ISRCTN78169443.

Cessation of smoking trial in the emergency department (CoSTED): protocol for a multicentre randomised controlled trial.

INTRODUCTION: Attendees of emergency departments (EDs) have a higher than expected prevalence of smoking. ED attendance may be a good opportunity to prompt positive behaviour change, even for smokers not currently motivated to quit. This study aims to determine whether an opportunist smoking cessation intervention delivered in the ED can help daily smokers attending the ED quit smoking and is cost-effective. METHODS AND ANALYSIS: A two-arm pragmatic, multicentred, parallel-group, individually randomised, controlled superiority trial with an internal pilot, economic evaluation and mixed methods process evaluation. The trial will compare ED-based brief smoking cessation advice, including provision of an e-cigarette and referral to local stop smoking services (intervention) with the provision of contact details for local stop smoking services (control). Target sample size is 972, recruiting across 6 National Health Service EDs in England and Scotland. Outcomes will be collected at 1, 3 and 6 months. The primary outcome at 6 months is carbon monoxide verified continuous smoking abstinence. ETHICS AND DISSEMINATION: The trial was approved by the South Central-Oxford B Research Committee (21/SC/0288). Dissemination will include the publication of outcomes, and the process and economic evaluations in peer-reviewed journals. The findings will also be appropriately disseminated to relevant practice, policy and patient representative groups. TRIAL REGISTRATION NUMBER: NCT04854616; protocol V.4.2.

Treating common mental disorder including psychotic experiences in the primary care improving access to psychological therapies programme (the TYPPEX study): protocol for a stepped wedge cluster randomised controlled trial with nested economic and process evaluation of a training package for therapists.

INTRODUCTION: At least one in four people treated by the primary care improving access to psychological therapies (IAPT) programme in England experiences distressing psychotic experiences (PE) in addition to common mental disorder (CMD). These individuals are less likely to achieve recovery. IAPT services do not routinely screen for nor offer specific treatments for CMD including PE. The Tailoring evidence-based psychological therapY for People with common mental disorder including Psychotic EXperiences study will evaluate the clinical and cost-effectiveness of an enhanced training for cognitive behavioural therapists that aims to address this clinical gap. METHODS AND ANALYSIS: This is a multisite, stepped-wedge cluster randomised controlled trial. The setting will be IAPT services within three mental health trusts. The participants will be (1) 56-80 qualified IAPT cognitive behavioural therapists and (2) 600 service users who are triaged as appropriate for cognitive behavioural therapy in an IAPT service and have PE according to the Community Assessment of Psychic Experiences-Positive 15-items Scale. IAPT therapists will be grouped into eight study clusters subsequently randomised to the control-intervention sequence. We will obtain pseudonymous clinical outcome data from IAPT clinical records for eligible service users. We will invite service users to complete health economic measures at baseline, 3, 6, 9 and 12-month follow-up. The primary outcome will be the proportion of patients with common mental disorder psychotic experiences who have recovered by the end of treatment as measured by the official IAPT measure for recovery. ETHICS AND DISSEMINATION: The study received the following approvals: South Central-Berkshire Research Ethics Committee on 28 April 2020 (REC reference 20/SC/0135) and Health Research Authority (HRA) on 23 June 2020. An amendment was approved by the Ethics Committee on 01 October 2020 and HRA on 27 October 2020. Results will be made available to patients and the public, the funders, stakeholders in the IAPT services and other researchers. TRIAL REGISTRATION NUMBER: ISRCTN93895792.

A multidomain decision support tool to prevent falls in older people: the FinCH cluster RCT.

BACKGROUND: Falls in care home residents are common, unpleasant, costly and difficult to prevent. OBJECTIVES: The objectives were to evaluate the clinical effectiveness and cost-effectiveness of the Guide to Action for falls prevention in Care Homes (GtACH) programme. DESIGN: A multicentre, cluster, parallel, 1 : 1 randomised controlled trial with embedded process evaluation and economic evaluation. Care homes were randomised on a 1 : 1 basis to the GtACH programme or usual care using a secure web-based randomisation service. Research assistants, participating residents and staff informants were blind to allocation at recruitment; research assistants were blind to allocation at follow-up. NHS Digital data were extracted blindly. SETTING: Older people's care homes from 10 UK sites. PARTICIPANTS: Older care home residents. INTERVENTION: The GtACH programme, which includes care home staff training, systematic use of a multidomain decision support tool and implementation of falls prevention actions, compared to usual falls prevention care. OUTCOMES: The primary trial outcome was the rate of falls per participating resident occurring during the 90-day period between 91 and 180 days post randomisation. The primary outcome for the cost-effectiveness analysis was the cost per fall averted, and the primary outcome for the cost-utility analysis was the incremental cost per quality adjusted life-year. Secondary outcomes included the rate of falls over days 0-90 and 181-360 post randomisation, activity levels, dependency and fractures. The number of falls per resident was compared between arms using a negative binomial regression model (generalised estimating equation). RESULTS: A total of 84 care homes were randomised: 39 to the GtACH arm and 45 to the control arm. A total of 1657 residents consented and provided baseline measures (mean age 85 years, 32% men). GtACH programme training was delivered to 1051 staff (71% of eligible staff) over 146 group sessions. Primary outcome data were available for 630 GtACH participants and 712 control participants. The primary outcome result showed an unadjusted incidence rate ratio of 0.57 (95% CI 0.45 to 0.71; p < 0.01) in favour of the GtACH programme. Falls rates were lower in the GtACH arm in the period 0-90 days. There were no other differences between arms in the secondary outcomes. Care home staff valued the training, systematic strategies and specialist peer support, but the incorporation of the GtACH programme documentation into routine care home practice was limited. No adverse events were recorded. The incremental cost was £20,889.42 per Dementia Specific Quality of Life-based quality-adjusted life-year and £4543.69 per quality-adjusted life-year based on the EuroQol-5 dimensions, five-level version. The mean number of falls was 1.889 (standard deviation 3.662) in the GtACH arm and 2.747 (standard deviation 7.414) in the control arm. Therefore, 0.858 falls were averted. The base-case incremental cost per fall averted was £190.62. CONCLUSION: The GtACH programme significantly reduced the falls rate in the study care homes without restricting residents' activity levels or increasing their dependency, and was cost-effective at current thresholds in the NHS. FUTURE WORK: Future work should include a broad implementation programme, focusing on scale and sustainability of the GtACH programme. LIMITATIONS: A key limitation was the fact that care home staff were not blinded, although risk was small because of the UK statutory requirement to record falls in care homes. TRIAL REGISTRATION: This trial is registered as ISRCTN34353836. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 9. See the NIHR Journals Library website for further project information.

Falls in care home residents are common, unpleasant, costly and hard to prevent. We tested whether or not the Guide to Action for falls prevention in Care Homes (GtACH) programme was effective in preventing falls. In this programme, care home staff were systematically trained and supported in the assessment of residents' risk of falling and the generation of a falls reduction care plan. We undertook a randomised controlled trial comparing the GtACH programme with usual care, which does not involve this systematic attention to falls prevention. We also undertook a process evaluation, observing organisational and care processes, and an economic study to evaluate value for money. A total of 39 care homes were randomly allocated to the GtACH programme and 45 care homes were randomly allocated to usual care, involving a total of 1657 residents. The main comparison between the two arms was the rate of falls during months 4­6 after randomisation, when we expected any effect to be at its peak. We also assessed the falls rates before and 6 months after this period. We measured activity and dependency levels, as it was important to be sure that any reduction in the rate of falls was not achieved through restrictive care practices. We saw a 43% reduction in the falls rates of the GtACH programme participants during months 4­6, without observing any reduction in residents' activity or dependency. Care home staff and relatives were positive about the GtACH programme. The GtACH programme was good value for money, as it was likely to be cost-effective. The effect of the programme waned over months 6­12, which may be because some staff did not embed the GtACH programme in their usual practice routines, and awareness levels may have dropped.

Design and rationale of a multi-center, pragmatic, open-label randomized trial of antimicrobial therapy - the study of clinical efficacy of antimicrobial therapy strategy using pragmatic design in Idiopathic Pulmonary Fibrosis (CleanUP-IPF) clinical trial.

Compelling data have linked disease progression in patients with idiopathic pulmonary fibrosis (IPF) with lung dysbiosis and the resulting dysregulated local and systemic immune response. Moreover, prior therapeutic trials have suggested improved outcomes in these patients treated with either sulfamethoxazole/ trimethoprim or doxycycline. These trials have been limited by methodological concerns. This trial addresses the primary hypothesis that long-term treatment with antimicrobial therapy increases the time-to-event endpoint of respiratory hospitalization or all-cause mortality compared to usual care treatment in patients with IPF. We invoke numerous innovative features to achieve this goal, including: 1) utilizing a pragmatic randomized trial design; 2) collecting targeted biological samples to allow future exploration of 'personalized' therapy; and 3) developing a strong partnership between the NHLBI, a broad range of investigators, industry, and philanthropic organizations. The trial will randomize approximately 500 individuals in a 1:1 ratio to either antimicrobial therapy or usual care. The site principal investigator will declare their preferred initial antimicrobial treatment strategy (trimethoprim 160 mg/ sulfamethoxazole 800 mg twice a day plus folic acid 5 mg daily or doxycycline 100 mg once daily if body weight is < 50 kg or 100 mg twice daily if ≥50 kg) for the participant prior to randomization. Participants randomized to antimicrobial therapy will receive a voucher to help cover the additional prescription drug costs. Additionally, those participants will have 4-5 scheduled blood draws over the initial 24 months of therapy for safety monitoring. Blood sampling for DNA sequencing and genome wide transcriptomics will be collected before therapy. Blood sampling for transcriptomics and oral and fecal swabs for determination of the microbiome communities will be collected before and after study completion. As a pragmatic study, participants in both treatment arms will have limited in-person visits with the enrolling clinical center. Visits are limited to assessments of lung function and other clinical parameters at time points prior to randomization and at months 12, 24, and 36. All participants will be followed until the study completion for the assessment of clinical endpoints related to hospitalization and mortality events. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02759120.

Self-Monitoring and Management of Blood Pressure in Patients with Stroke or TIA: An Economic Evaluation of TEST-BP, A Randomised Controlled Trial.

BACKGROUND: Prevention of secondary stroke following initial ictus is an important focus of after-stroke care. Blood pressure (BP) is a key risk factor, so usual care following stroke or transient ischaemic attack includes regular BP checks and monitoring of anti-hypertensive medication. This is traditionally carried out in primary care, but the evidence supporting self-monitoring and self-guided management of BP in the general population with hypertension is growing. OBJECTIVE: Our objective was to estimate the cost effectiveness of treatment as usual (TAU) versus (1) self-monitoring of BP (S-MON) and (2) self-monitoring and guided self-management of anti-hypertensive medication (S-MAN). METHODS: This was a within-trial economic evaluation of a randomised controlled trial estimating the incremental cost per 1 mmHg BP reduction and per quality-adjusted life-year (QALY) gained over a 6-month time horizon from the perspective of the UK National Health Service (NHS). RESULTS: Data were evaluable for 140 participants. Costs per patient were £473, £853 and £1035; mean reduction in systolic BP (SBP) was 3.6, 6.7 and 6.1 mmHg, and QALYs accrued were 0.427, 0.422 and 0.423 for TAU, S-MON and S-MAN, respectively. No statistically significant differences in incremental costs or outcomes were detected. On average, S-MAN was dominated or extended dominated. The incremental cost per 1 mmHg BP reduction from S-MON versus TAU was £137. CONCLUSION: On average, S-MAN is an inefficient intervention. S-MON may be cost effective, depending on the willingness to pay for a 1 mmHg BP reduction, although it yielded fewer QALYs over the within-trial time horizon. Decision modelling is required to explore the longer-term costs and outcomes.

At-risk registers integrated into primary care to stop asthma crises in the UK (ARRISA-UK): study protocol for a pragmatic, cluster randomised trial with nested health economic and process evaluations.

BACKGROUND: Despite effective treatments and long-standing management guidelines, there are approximately 1400 hospital admissions for asthma weekly in the United Kingdom (UK), many of which could be avoided. In our previous research, a secondary analysis of the intervention (ARRISA) suggested an improvement in the management of at-risk asthma patients in primary care. ARRISA involved identifying individuals at risk of adverse asthma events, flagging their electronic health records, training practice staff to develop and implement practice-wide processes of care when alerted by the flag, plus motivational reminders. We now seek to determine the effectiveness and cost-effectiveness of ARRISA in reducing asthma-related crisis events. METHODS: We are undertaking a pragmatic, two-arm, multicentre, cluster randomised controlled trial, plus health economic and process evaluation. We will randomise 270 primary care practices from throughout the UK covering over 10,000 registered patients with 'at-risk asthma' identified according to a validated algorithm. Staff in practices randomised to the intervention will complete two 45-min eLearning modules (an individually completed module giving background to ARRISA and a group-completed module to develop practice-wide pathways of care) plus a 30-min webinar with other practices. On completion of training at-risk patients' records will be coded so that a flag appears whenever their record is accessed. Practices will receive a phone call at 4 weeks and a reminder video at 6 weeks and 6 months. Control practices will continue to provide usual care. We will extract anonymised routine patient data from primary care records (with linkage to secondary care data) to determine the percentage of at-risk patients with an asthma-related crisis event (accident and emergency attendances, hospitalisations and deaths) after 12 months (primary outcome). We will also capture the time to crisis event, all-cause hospitalisations, asthma control and any changes in practice asthma management for at-risk and all patients with asthma. Cost-effectiveness analysis and mixed-methods process evaluations will also be conducted. DISCUSSION: This study is novel in terms of using a practice-wide intervention to target and engage with patients at risk from their asthma and is innovative in the use of routinely captured data with record linkage to obtain trial outcomes. TRIAL REGISTRATION: ISRCTN95472706 . Registered on 5 December 2014.

Improving access to high-quality primary care for socioeconomically disadvantaged older people in rural areas: a mixed method study protocol.

INTRODUCTION: The UK has an ageing population, especially in rural areas, where deprivation is high among older people. Previous research has identified this group as at high risk of poor access to healthcare. The aim of this study is to generate a theory of how socioeconomically disadvantaged older people from rural areas access primary care, to develop an intervention based on this theory and test it in a feasibility trial. METHODS AND ANALYSIS: On the basis of the MRC Framework for Developing and Evaluating Complex Interventions, three methods will be used to generate the theory. First, a realist review will elucidate the patient pathway based on existing literature. Second, an analysis of the English Longitudinal Study of Ageing will be completed using structural equation modelling. Third, 15 semistructured interviews will be undertaken with patients and four focus groups with health professionals. A triangulation protocol will be used to allow each of these methods to inform and be informed by each other, and to integrate data into one overall realist theory. Based on this theory, an intervention will be developed in discussion with stakeholders to ensure that the intervention is feasible and practical. The intervention will be tested within a feasibility trial, the design of which will depend on the intervention. Lessons from the feasibility trial will be used to refine the intervention and gather the information needed for a definitive trial. ETHICS AND DISSEMINATION: Ethics approval from the regional ethics committee has been granted for the focus groups with health professionals and interviews with patients. Ethics approval will be sought for the feasibility trial after the intervention has been designed. Findings will be disseminated to the key stakeholders involved in intervention development, to researchers, clinicians and health planners through peer-reviewed journal articles and conference publications, and locally through a dissemination event.

Treating idiopathic pulmonary fibrosis with the addition of co-trimoxazole: an economic evaluation alongside a randomised controlled trial.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a fibrotic disease of the lungs of unknown origin with a poor prognosis. A small trial of co-trimoxazole demonstrated improvements in symptoms and functional parameters over a 3-month period. We therefore conducted a larger trial with a concurrent economic evaluation to investigate this antibiotic further. METHODS: We report an economic evaluation alongside a multi-centre, randomised, placebo-controlled, double-blind trial of 12 months therapy with 960 mg co-trimoxazole daily in 181 patients with fibrotic idiopathic interstitial pneumonia (IIP). Patients were recruited from 28 university and district hospitals in the UK and were aged over 40 years with fibrotic IIP. We report costs to the National Health Service (NHS) and society, change in forced vital capacity (primary endpoint) and quality-adjusted life-years (QALYs) gained, incremental cost effectiveness and cost utility ratios over 12 months. RESULTS: From the perspective of society, mean cost per patient in the co-trimoxazole arm was approximately £1177 higher than in the placebo arm, but mean QALYs were 0.053 higher yielding an incremental cost-effectiveness ratio of £22,012 per QALY gained with a 54.44 % probability of being below £30,000. The cost of IPF to UK society in 2011 is tentatively estimated at £124 million, of which 13 % is NHS costs, 1 % social services, 2 % patient out-of-pocket costs and 84 % lost productivity. CONCLUSIONS: Given commonly employed thresholds in the UK NHS, on balance co-trimoxazole may be a cost-effective treatment for IPF, although there is substantial decision uncertainty. However, recent guidance on the use of immunosuppressive therapy in IPF patients should be taken into account prior to any policy decision.

Do referral-management schemes reduce hospital outpatient attendances? Time-series evaluation of primary care referral management.

BACKGROUND: Ninety-one per cent of primary care trusts were using some form of referral management in 2009, although evidence for its effectiveness is limited. AIM: To assess the impact of three referral-management centres (RMCs) and two internal peer-review approaches to referral management on hospital outpatient attendance rates. DESIGN AND SETTING: A retrospective time-series analysis of 376 000 outpatient attendances over 3 years from 85 practices divided into five groups, with 714 000 registered patients in one English primary care trust. METHOD: The age-standardised GP-referred first outpatient monthly attendance rate was calculated for each group from April 2009 to March 2012. This was divided by the equivalent monthly England rate, to derive a rate ratio. Linear regression tested for association between the introduction of referral management and change in the outpatient attendance rate and rate ratio. Annual group budgets for referral management were obtained. RESULTS: Referral management was not associated with a reduction in the outpatient attendance rate in any group. There was a statistically significant increase in attendance rate in one group (a RMC), which had an increase of 1.05 attendances per 1000 persons per month (95% confidence interval = 0.46 to 1.64; attendance rate ratio increase of 0.07) after adjustment for autocorrelation. Mean annual budgets ranged from £0.55 to £6.23 per registered patient in 2011/2012. RMCs were more expensive (mean annual budget £5.18 per registered patient) than internal peer-review approaches (mean annual budget £0.97 per registered patient). CONCLUSION: Referral-management schemes did not reduce outpatient attendance rates. RMCs were more expensive than internal peer review.

Health sector costs of self-reported food allergy in Europe: a patient-based cost of illness study.

INTRODUCTION: Food allergy is a recognized health problem, but little has been reported on its cost for health services. The EuroPrevall project was a European study investigating the patterns, prevalence and socio-economic cost of food allergy. AIMS: To investigate the health service cost for food-allergic Europeans and the relationship between severity and cost of illness. METHODS: Participants recruited through EuroPrevall studies in a case-control study in four countries, and cases only in five countries, completed a validated economics questionnaire. Individuals with possible food allergy were identified by clinical history, and those with food-specific immunoglobulin E were defined as having probable allergy. Data on resource use were used to estimate total health care costs of illness. Mean costs were compared in the case-control cohorts. Regression analysis was conducted on cases from all 9 countries to assess impact of country, severity and age group. RESULTS: Food-allergic individuals had higher health care costs than controls. The mean annual cost of health care was international dollars (I$)2016 for food-allergic adults and I$1089 for controls, a difference of I$927 (95% confidence interval I$324-I$1530). A similar result was found for adults in each country, and for children, and was not sensitive to baseline demographic differences. Cost was significantly related to severity of illness in cases in nine countries. CONCLUSIONS: Food allergy is associated with higher health care costs. Severity of allergic symptoms is a key explanatory factor.

Bayesian methods of analysis for cluster randomized trials with count outcome data.

Bayesian approaches to inference in cluster randomized trials have been investigated for normally distributed and binary outcome measures. However, relatively little attention has been paid to outcome measures which are counts of events. We discuss an extension of previously published Bayesian hierarchical models to count data, which usually can be assumed to be distributed according to a Poisson distribution. We develop two models, one based on the traditional rate ratio, and one based on the rate difference which may often be more intuitively interpreted for clinical trials, and is needed for economic evaluation of interventions. We examine the relationship between the intracluster correlation coefficient (ICC) and the between-cluster variance for each of these two models. In practice, this allows one to use the previously published evidence on ICCs to derive an informative prior distribution which can then be used to increase the precision of the posterior distribution of the ICC. We demonstrate our models using a previously published trial assessing the effectiveness of an educational intervention and a prior distribution previously derived. We assess the robustness of the posterior distribution for effectiveness to departures from a normal distribution of the random effects.

Surveillance of individual level disease maps.

Methods for the production of individual (address) level disease maps are often retrospective; they estimate a map of the average relative risk of disease over a study period. However, recently, epidemiologists have started to look at weekly or monthly reports of disease and assess them for any change in the distribution of relative risk. For example, in the United States of America, the Centre for Disease Control and Prevention now routinely collects information on over 50 notifiable diseases every week. In this paper we present a method for the detection of a sudden change in the geographical distribution of the disease in a prospective study. The method is based on an estimate of the directional derivative of the conditional probability of a case, given either a case or control has occurred. It is based on standard kernel approaches to nonparametric regression and it is readily applied in any standard statistical software package. Two simulated examples of sudden clustering around a fixed point are provided.