Early versus delayed weight-bearing following operatively treated ankle fracture (WAX): a non-inferiority, multicentre, randomised controlled trial.

BACKGROUND: After surgery for a broken ankle, patients are usually instructed to avoid walking for 6 weeks (delayed weight-bearing). Walking 2 weeks after surgery (early weight-bearing) might be a safe and preferable rehabilitation strategy. This study aimed to determine the clinical and cost effectiveness of an early weight-bearing strategy compared with a delayed weight-bearing strategy. METHODS: This was a pragmatic, multicentre, randomised, non-inferiority trial including 561 participants (aged ≥18 years) who received acute surgery for an unstable ankle fracture in 23 UK National Health Service (NHS) hospitals who were assigned to either a delayed weight-bearing (n=280) or an early weight-bearing rehabilitation strategy (n=281). Patients treated with a hindfoot nail, those who did not have protective ankle sensation (eg, peripheral neuropathy), did not have the capacity to consent, or did not have the ability to adhere to trial procedures were excluded. Neither participants nor clinicians were masked to the treatment. The primary outcome was ankle function measured using the Olerud and Molander Ankle Score (OMAS) at 4 months after randomisation, in the per-protocol population. The pre-specified non-inferiority OMAS margin was -6 points and superiority testing was included in the intention-to-treat population in the event of non-inferiority. The trial was prospectively registered with ISRCTN Registry, ISRCTN12883981, and the trial is closed to new participants. FINDINGS: Primary outcome data were collected from 480 (86%) of 561 participants. Recruitment was conducted between Jan 13, 2020, and Oct 29, 2021. At 4 months after randomisation, the mean OMAS score was 65·9 in the early weight-bearing and 61·2 in the delayed weight-bearing group and adjusted mean difference was 4·47 (95% CI 0·58 to 8·37, p=0·024; superiority testing adjusted difference 4·42, 95% CI 0·53 to 8·32, p=0·026) in favour of early weight-bearing. 46 (16%) participants in the early weight-bearing group and 39 (14%) in the delayed weight-bearing group had one or more complications (adjusted odds ratio 1·18, 95% CI 0·80 to 1·75, p=0·40). The mean costs from the perspective of the NHS and personal social services in the early and delayed weight-bearing groups were £725 and £785, respectively (mean difference -£60 [95% CI -342 to 232]). The probability that early weight-bearing is cost-effective exceeded 80%. INTERPRETATION: An early weight-bearing strategy was found to be clinically non-inferior and highly likely to be cost-effective compared with the current standard of care (delayed weight-bearing). FUNDING: National Institute for Health and Care Research (NIHR), NIHR Barts Biomedical Research Centre, and NIHR Applied Research Collaboration Oxford and Thames Valley.

CARE: Protocol of a randomised trial evaluating the feasibility of preoperative intentional weight loss to support postoperative recovery in patients with excess weight and colorectal cancer.

AIM: Excess weight increases the risk of morbidity following colorectal cancer surgery. Weight loss may improve morbidity, but it is uncertain whether patients can follow an intensive weight loss intervention while waiting for surgery and there are concerns about muscle mass loss. The aim of this trial is to assess the feasibility of intentional weight loss in this setting and determine progression to a definitive trial. METHODS: CARE is a prospectively registered, multicentre, feasibility, parallel, randomised controlled trial with embedded evaluation and optimisation of the recruitment process. Participants with excess weight awaiting curative colorectal resection for cancer are randomised 1:1 to care as usual or a low-energy nutritionally-replete total diet replacement programme with weekly remote behavioural support by a dietitian. Progression criteria will be based on the recruitment, engagement, adherence, and retention rates. Data will be collected on the 30-day postoperative morbidity, the typical primary outcome of prehabilitation trials. Secondary outcomes will include, among others, length of hospital stay, health-related quality of life, and body composition. Qualitative interviews will be used to understand patients' experiences of and attitudes towards trial participation and intervention engagement and adherence. CONCLUSION: CARE will evaluate the feasibility of intensive intentional weight loss as prehabilitation before colorectal cancer surgery. The results will determine the planning of a definitive trial.

Mapping between headache specific and generic preference-based health-related quality of life measures.

BACKGROUND: The Headache Impact Test (HIT-6) and the Chronic Headache Questionnaire (CH-QLQ) measure headache-related quality of life but are not preference-based and therefore cannot be used to generate health utilities for cost-effectiveness analyses. There are currently no established algorithms for mapping between the HIT-6 or CH-QLQ and preference-based health-related quality-of-life measures for chronic headache population. METHODS: We developed algorithms for generating EQ-5D-5L and SF-6D utilities from the HIT-6 and the CHQLQ using both direct and response mapping approaches. A multi-stage model selection process was used to assess the predictive accuracy of the models. The estimated mapping algorithms were derived to generate UK tariffs and was validated using the Chronic Headache Education and Self-management Study (CHESS) trial dataset. RESULTS: Several models were developed that reasonably accurately predict health utilities in this context. The best performing model for predicting EQ-5D-5L utility scores from the HIT-6 scores was a Censored Least Absolute Deviations (CLAD) (1) model that only included the HIT-6 score as the covariate (mean squared error (MSE) 0.0550). The selected model for CH-QLQ to EQ-5D-5L was the CLAD (3) model that included CH-QLQ summary scores, age, and gender, squared terms and interaction terms as covariates (MSE 0.0583). The best performing model for predicting SF-6D utility scores from the HIT-6 scores was the CLAD (2) model that included the HIT-6 score and age and gender as covariates (MSE 0.0102). The selected model for CH-QLQ to SF-6D was the OLS (2) model that included CH-QLQ summary scores, age, and gender as covariates (MSE 0.0086). CONCLUSION: The developed algorithms enable the estimation of EQ-5D-5L and SF-6D utilities from two headache-specific questionnaires where preference-based health-related quality of life data are missing. However, further work is needed to help define the best approach to measuring health utilities in headache studies.

Economic costs and health utility values associated with extremely preterm birth: Evidence from the EPICure2 cohort study.

BACKGROUND: Preterm birth is associated with adverse health and developmental sequelae that impose a burden on finite resources and significant challenges for individuals, families and societies. OBJECTIVES: To estimate economic outcomes at age 11 associated with extremely preterm birth using evidence from a whole population study (EPICure2 study). METHODS: The study population comprised a sample of children born at ≤26 completed weeks of gestation during 2006 in England (n = 200) and a comparison group of classmates born at term (n = 143). Societal costs were estimated using parent and teacher reports of service utilisation, and valuations of work losses and additional care costs to families. Utility scores for the Health Utilities Index Mark 2 (HUI2) and Mark 3 (HUI3) were generated using UK and Canadian value sets. Generalised linear regression was used to estimate the impact of extremely preterm birth on societal costs and utility scores. RESULTS: Unadjusted mean societal costs that excluded provision of special educational support in mainstream schools during the 11th year after birth were £6536 for the extremely preterm group and £3275 for their classmates, generating a difference of £3262 (95% confidence interval [CI] £1912, £5543). The mean adjusted cost difference was £2916 (95% CI £1609, £4224), including special educational needs provision in mainstream schools increased the adjusted cost difference to £4772 (95% CI £3166, £6378). Compared with birth at term, extremely preterm birth generated mean-adjusted utility decrements ranging from 0.13 (95% CI 0.09, 0.18) based on the UK HUI2 statistical inference tariff to 0.28 (95% CI 0.18, 0.37) based on the Canadian HUI3 tariff. CONCLUSIONS: The adverse economic impact of extremely preterm birth persists into late childhood. Further longitudinal studies conducted from multiple perspectives are needed to understand the magnitude, trajectory and underpinning mechanisms of economic outcomes following extremely preterm birth.

Measuring health-related quality of life in chronic headache: A comparative evaluation of the Chronic Headache Quality of Life Questionnaire and Headache Impact Test (HIT-6).

OBJECTIVE: To compare the quality and acceptability of a new headache-specific patient-reported measure, the Chronic Headache Quality of Life Questionnaire (CHQLQ) with the six-item Headache Impact Test (HIT-6), in people meeting an epidemiological definition of chronic headaches. METHODS: Participants in the feasibility stage of the Chronic Headache Education and Self-management Study (CHESS) (n = 130) completed measures three times during a 12-week prospective cohort study. Data quality, measurement acceptability, reliability, validity, responsiveness to change, and score interpretation were determined. Semi-structured cognitive interviews explored measurement relevance, acceptability, clarity, and comprehensiveness. RESULTS: Both measures were well completed with few missing items. The CHQLQ's inclusion of emotional wellbeing items increased its relevance to participant's experience of chronic headache. End effects were present at item level only for both measures. Structural assessment supported the three and one-factor solutions of the CHQLQ and HIT-6, respectively. Both the CHQLQ (range 0.87 to 0.94) and HIT-6 (0.90) were internally consistent, with acceptable temporal stability over 2 weeks (CHQLQ range 0.74 to 0.80; HIT-6 0.86). Both measures responded to change in headache-specific health at 12 weeks (CHQLQ smallest detectable change (improvement) range 3 to 5; HIT-6 2.1). CONCLUSIONS: While both measures are structurally valid, internally consistent, temporally stable, and responsive to change, the CHQLQ has greater relevance to the patient experience of chronic headache.Trial registration number: ISRCTN79708100. Registered 16th December 2015, http://www.isrctn.com/ISRCTN79708100.

Can levosimendan reduce ECMO weaning failure in cardiogenic shock?: a cohort study with propensity score analysis.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has been increasingly used over the last decade in patients with refractory cardiogenic shock. ECMO weaning can, however, be challenging and lead to circulatory failure and death. Recent data suggest a potential benefit of levosimendan for ECMO weaning. We sought to further investigate whether the use of levosimendan could decrease the rate of ECMO weaning failure in adult patients with refractory cardiogenic shock. METHODS: We performed an observational single-center cohort study. All patients undergoing VA-ECMO from January 2012 to December 2018 were eligible and divided into two groups: group levosimendan and group control (without levosimendan). The primary endpoint was VA-ECMO weaning failure defined as death during VA-ECMO treatment or within 24 h after VA-ECMO removal. Secondary outcomes were mortality at day 28 and at 6 months. The two groups were compared after propensity score matching. P < 0.05 was considered statistically significant. RESULTS: Two hundred patients were analyzed (levosimendan group: n = 53 and control group: n = 147). No significant difference was found between groups on baseline characteristics except for ECMO duration, which was longer in the levosimendan group (10.6 ± 4.8 vs. 6.5 ± 4.7 days, p < 0.001). Levosimendan administration started 6.6 ± 5.4 days on average following ECMO implantation. After matching of 48 levosimendan patients to 78 control patients, the duration of ECMO was similar in both groups. The rate of weaning failure was 29.1% and 35.4% in levosimendan and control groups, respectively (OR: 0.69, 95%CI: 0.25-1.88). No significant difference was found between groups for all secondary outcomes. CONCLUSION: Levosimendan did not improve the rate of successful VA-ECMO weaning in patients with refractory cardiogenic shock. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04323709 .

Correction to: Can levosimendan reduce ECMO weaning failure in cardiogenic shock?: a cohort study with propensity score analysis.

An amendment to this paper has been published and can be accessed via the original article.

Cost-effectiveness of adrenaline for out-of-hospital cardiac arrest.

BACKGROUND: The 'Prehospital Assessment of the Role of Adrenaline: Measuring the Effectiveness of Drug Administration In Cardiac Arrest' (PARAMEDIC2) trial showed that adrenaline improves overall survival, but not neurological outcomes. We sought to determine the within-trial and lifetime health and social care costs and benefits associated with adrenaline, including secondary benefits from organ donation. METHODS: We estimated the costs, benefits (quality-adjusted life years (QALYs)) and incremental cost-effectiveness ratios (ICERs) associated with adrenaline during the 6-month trial follow-up. Model-based analyses explored how results altered when the time horizon was extended beyond 6 months and the scope extended to include recipients of donated organs. RESULTS: The within-trial (6 months) and lifetime horizon economic evaluations focussed on the trial population produced ICERs of £1,693,003 (€1,946,953) and £81,070 (€93,231) per QALY gained in 2017 prices, respectively, reflecting significantly higher mean costs and only marginally higher mean QALYs in the adrenaline group. The probability that adrenaline is cost-effective was less than 1% across a range of cost-effectiveness thresholds. Combined direct economic effects over the lifetimes of survivors and indirect economic effects in organ recipients produced an ICER of £16,086 (€18,499) per QALY gained for adrenaline with the probability that adrenaline is cost-effective increasing to 90% at a £30,000 (€34,500) per QALY cost-effectiveness threshold. CONCLUSIONS: Adrenaline was not cost-effective when only directly related costs and consequences are considered. However, incorporating the indirect economic effects associated with transplanted organs substantially alters cost-effectiveness, suggesting decision-makers should consider the complexity of direct and indirect economic impacts of adrenaline. TRIAL REGISTRATION: ISRCTN73485024 . Registered on 13 March 2014.

COSCA (Core Outcome Set for Cardiac Arrest) in Adults: An Advisory Statement From the International Liaison Committee on Resuscitation.

Cardiac arrest effectiveness trials have traditionally reported outcomes that focus on survival. A lack of consistency in outcome reporting between trials limits the opportunities to pool results for meta-analysis. The COSCA initiative (Core Outcome Set for Cardiac Arrest), a partnership between patients, their partners, clinicians, research scientists, and the International Liaison Committee on Resuscitation, sought to develop a consensus core outcome set for cardiac arrest for effectiveness trials. Core outcome sets are primarily intended for large, randomized clinical effectiveness trials (sometimes referred to as pragmatic trials or phase III/IV trials) rather than for pilot or efficacy studies. A systematic review of the literature combined with qualitative interviews among cardiac arrest survivors was used to generate a list of potential outcome domains. This list was prioritized through a Delphi process, which involved clinicians, patients, and their relatives/partners. An international advisory panel narrowed these down to 3 core domains by debate that led to consensus. The writing group refined recommendations for when these outcomes should be measured and further characterized relevant measurement tools. Consensus emerged that a core outcome set for reporting on effectiveness studies of cardiac arrest (COSCA) in adults should include survival, neurological function, and health-related quality of life. This should be reported as survival status and modified Rankin scale score at hospital discharge, at 30 days, or both. Health-related quality of life should be measured with ≥1 tools from Health Utilities Index version 3, Short-Form 36-Item Health Survey, and EuroQol 5D-5L at 90 days and at periodic intervals up to 1 year after cardiac arrest, if resources allow.

Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial.

BACKGROUND: Femoroacetabular impingement syndrome is an important cause of hip pain in young adults. It can be treated by arthroscopic hip surgery, including reshaping the hip, or with physiotherapist-led conservative care. We aimed to compare the clinical effectiveness of hip arthroscopy with best conservative care. METHODS: UK FASHIoN is a pragmatic, multicentre, assessor-blinded randomised controlled trial, done at 23 National Health Service hospitals in the UK. We enrolled patients with femoroacetabular impingement syndrome who presented at these hospitals. Eligible patients were at least 16 years old, had hip pain with radiographic features of cam or pincer morphology but no osteoarthritis, and were believed to be likely to benefit from hip arthroscopy. Patients with bilateral femoroacetabular impingement syndrome were eligible; only the most symptomatic hip was randomly assigned to treatment and followed-up. Participants were randomly allocated (1:1) to receive hip arthroscopy or personalised hip therapy (an individualised, supervised, and progressive physiotherapist-led programme of conservative care). Randomisation was stratified by impingement type and recruiting centre and was done by research staff at each hospital, using a central telephone randomisation service. Patients and treating clinicians were not masked to treatment allocation, but researchers who collected the outcome assessments and analysed the results were masked. The primary outcome was hip-related quality of life, as measured by the patient-reported International Hip Outcome Tool (iHOT-33) 12 months after randomisation, and analysed in all eligible participants who were allocated to treatment (the intention-to-treat population). This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN64081839, and is closed to recruitment. FINDINGS: Between July 20, 2012, and July 15, 2016, we identified 648 eligible patients and recruited 348 participants: 171 participants were allocated to receive hip arthroscopy and 177 to receive personalised hip therapy. Three further patients were excluded from the trial after randomisation because they did not meet the eligibility criteria. Follow-up at the primary outcome assessment was 92% (319 of 348 participants). At 12 months after randomisation, mean iHOT-33 scores had improved from 39·2 (SD 20·9) to 58·8 (27·2) for participants in the hip arthroscopy group, and from 35·6 (18·2) to 49·7 (25·5) in the personalised hip therapy group. In the primary analysis, the mean difference in iHOT-33 scores, adjusted for impingement type, sex, baseline iHOT-33 score, and centre, was 6·8 (95% CI 1·7-12·0) in favour of hip arthroscopy (p=0·0093). This estimate of treatment effect exceeded the minimum clinically important difference (6·1 points). There were 147 patient-reported adverse events (in 100 [72%] of 138 patients) in the hip arthroscopy group) versus 102 events (in 88 [60%] of 146 patients) in the personalised hip therapy group, with muscle soreness being the most common of these (58 [42%] vs 69 [47%]). There were seven serious adverse events reported by participating hospitals. Five (83%) of six serious adverse events in the hip arthroscopy group were related to treatment, and the one in the personalised hip therapy group was not. There were no treatment-related deaths, but one patient in the hip arthroscopy group developed a hip joint infection after surgery. INTERPRETATION: Hip arthroscopy and personalised hip therapy both improved hip-related quality of life for patients with femoroacetabular impingement syndrome. Hip arthroscopy led to a greater improvement than did personalised hip therapy, and this difference was clinically significant. Further follow-up will reveal whether the clinical benefits of hip arthroscopy are maintained and whether it is cost effective in the long term. FUNDING: The Health Technology Assessment Programme of the National Institute of Health Research.

A bootstrapping approach for generating an inverse distance weight matrix when multiple observations have an identical location in large health surveys.

Spatial weight matrices play a key role in econometrics to capture spatial effects. However, these constructs are prone to clustering and can be challenging to analyse in common statistical packages such as STATA. Multiple observations of survey participants in the same location (or cluster) have traditionally not been dealt with appropriately by statistical packages. It is common that participants are assigned Geographic Information System (GIS) data at a regional or district level rather than at a small area level. For example, the Demographic Health Survey (DHS) generates GIS data at a cluster level, such as a regional or district level, rather than providing coordinates for each participant. Moreover, current statistical packages are not suitable for estimating large matrices such as 20,000 × 20,000 (reflective of data within large health surveys) since the statistical package limits the N to a smaller number. In addition, in many cases, GIS information is offered at an aggregated level of geographical areas. To alleviate this problem, this paper proposes a bootstrap approach that generates an inverse distance spatial weight matrix for application in econometric analyses of health survey data. The new approach is illustrated using DHS data on uptake of HIV testing in low and middle income countries.

Cost-effectiveness of internet-based training for primary care clinicians on antibiotic prescribing for acute respiratory tract infections in Europe.

Objectives: Overprescribing of antibiotics by general practitioners (GPs) is seen as a major driver of antibiotic resistance. Training in communication skills and C-reactive protein (CRP) testing both appear effective in reducing such prescribing. This study assesses the cost-effectiveness (compared with usual care) of: (i) training GPs in the use of CRP testing; (ii) training GPs in communication skills; and (iii) training GPs in both CRP testing and communication skills. Methods: Economic analyses [cost-utility analysis (CUA) accounting for the cost of antibiotic resistance and cost-effectiveness analysis (CEA)] were both conducted from a healthcare perspective with a time horizon of 28 days alongside a multinational, cluster, randomized, factorial controlled trial in patients with respiratory tract infections in five European countries. The primary outcome measures were QALYs and percentage reduction in antibiotic prescribing. Hierarchical modelling was used to estimate an incremental cost per QALY gained and an incremental cost per percentage reduction in antibiotic prescribing. Results: Overall, the results of both the CUA and CEA showed that training in communication skills is the most cost-effective option. However, excluding the cost of antibiotic resistance in the CUA resulted in usual care being the most cost-effective option. Country-specific results from the CUA showed that training in communication skills was cost-effective in Belgium, UK and Netherlands whilst training in CRP was cost-effective in Poland. Conclusions: Internet-based training in communication skills is a cost-effective intervention to reduce antibiotic prescribing for respiratory tract infections in primary care if the cost of antibiotic resistance is accounted for.

Long-term mortality after acute myocardial infarction among individuals with and without diabetes: A systematic review and meta-analysis of studies in the post-reperfusion era.

AIMS: To conduct a systematic review and meta-analysis with the aim of providing robust estimates of the association between diabetes and long-term (≥1 year) mortality after acute myocardial infarction (AMI). MATERIAL AND METHODS: Medline, Embase and Web of Science databases were searched (January 1985 to July 2016) for terms related to long-term mortality, diabetes and AMI. Two authors independently abstracted the data. Hazard ratios (HRs) comparing mortality in people with and without diabetes were pooled across studies using Bayesian random-effects meta-analysis. RESULTS: A total of 10 randomized controlled trials and 56 cohort studies, including 714 780 patients, reported an estimated total of 202 411 deaths over the median (range) follow-up of 2.0 (1-20) years. The risk of death over time was significantly higher among those with diabetes compared with those without (unadjusted HR 1.82, 95% credible interval [CrI] 1.73-1.91). Mortality remained higher in the analysis restricted to 23/64 cohorts reporting data adjusted for confounders (adjusted HR 1.48, 95% CrI 1.43-1.53). The excess long-term mortality in diabetes was evident irrespective of the phenotype and modern treatment of AMI, and persisted in early survivors (unadjusted HR 1.82, 95% CrI 1.70-1.95). CONCLUSIONS: Despite medical advances, individuals with diabetes have a 50% greater long-term mortality compared with those without. Further research to understand the determinants of this excess risk are important for public health, given the predicted rise in global diabetes prevalence.

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.

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.

Childhood Transitions Between Weight Status Categories: Evidence from the UK Millennium Cohort Study.

BACKGROUND: Assessing the cost-effectiveness of interventions targeting childhood excess weight requires estimates of the hazards of transitioning between weight status categories. Current estimates are based on studies characterized by insufficient sample sizes, a lack of national representativeness, and untested assumptions. OBJECTIVES: We sought to (1) estimate transition probabilities and hazard ratios for transitioning between childhood weight status categories, (2) test the validity of the underlying assumption in the literature that transitions between childhood bodyweight categories are time-homogeneous, (3) account for complex sampling procedures when deriving nationally representative transition estimates, and (4) explore the impact of child, maternal, and sociodemographic characteristics. METHODS: We applied a multistate transition modeling approach accounting for complex survey design to UK Millennium Cohort Study (MCS) data to predict transition probabilities and hazard ratios for weight status movements for children aged 3-17. Surveys were conducted at ages 3 (wave 2 in 2004), 5 (wave 3 in 2006), 7 (wave 4 in 2008), 11 (wave 5 in 2012), 14 (wave 6 in 2015), and 17 (wave 7 in 2018) years. We derived datasets that included repeated body mass index measurements across waves after excluding multiple births and children with missing or implausible bodyweight records. To account for the stratified cluster sample design of the MCS, we incorporated survey weights and jackknife replicates of survey weights. Using a validation dataset from the MCS, we tested the validity of our models. Finally, we estimated the relationships between state transitions and child, maternal, and sociodemographic factors. RESULTS: The datasets for our primary analysis consisted of 10,399 children for waves 2-3, 10,729 for waves 3-4, 9685 for waves 4-5, 8593 for waves 5-6, and 7085 for waves 6-7. All datasets consisted of roughly equal splits of boys and girls. Under the assumption of time-heterogeneous transition rates (our base-case model), younger children (ages 3-5 and 5-7 years) had significantly higher annual transition probabilities of moving from healthy weight to overweight (0.033, 95% confidence interval [CI] 0.026-0.041, and 0.027, 95% CI 0.021-0.033, respectively) compared to older children (0.015, 95% CI 0.012-0.018, at ages 7-11; 0.018, 95% CI 0.013-0.023, at ages 11-14; and 0.018, 95% CI 0.013-0.025 at ages 14-17 years). However, the resolution of unhealthy weight was more strongly age-dependent than transitions from healthy weight to non-healthy weight states. Transition hazards differed by child, maternal, and sociodemographic factors. CONCLUSIONS: Our models generated estimates of bodyweight status transitions in a representative UK childhood population. Compared to our scenario models (i.e., time-homogeneous transition rates), our base-case model fits the observed data best, indicating a non-time-homogeneous pattern in transitions between bodyweight categories during childhood. Transition hazards varied significantly by age and across subpopulations, suggesting that conducting subgroup-specific cost-effectiveness analyses of childhood weight management interventions will optimize decision-making.

Pre-existing musculoskeletal pain and its association with mortality in newly diagnosed co-morbid conditions: an electronic health record cohort study.

Objective: Musculoskeletal pain is a common risk factor for co-morbid conditions and might increase the risk of poor outcomes. The objective was to determine whether patients with pre-existing musculoskeletal pain have an increased risk for mortality following a new diagnosis of a co-morbid condition. Methods: Patients aged ≥45 years with a new diagnosis of acute coronary syndrome (ACS), stroke, cancer, dementia or pneumonia recorded in a UK electronic primary care database linked to hospital and mortality records were examined. The association of mortality with musculoskeletal pain (inflammatory conditions, OA and regional pain) was determined. Results: The sample size varied from 128 649 (stroke) to 406 289 (cancer) by cohort, with 22-31% having pre-existing musculoskeletal conditions. In the ACS cohort, there was a higher rate of mortality for all musculoskeletal types. There were also higher unadjusted mortality rates in patients with inflammatory arthritis compared with those without musculoskeletal pain in the stroke, cancer and dementia cohorts and for patients with OA in the stroke and cancer cohorts. After adjustment for the number of prescribed medications and age, the increased risk of mortality remained only for patients with inflammatory arthritis in the ACS cohort (adjusted hazard ratio = 1.07; 95% CI 1.03, 1.10). Conclusion: Older adults with inflammatory arthritis and OA have increased risk of mortality when they develop a new condition, which seems to be related to the prescription of multiple medicines. Pre-existing musculoskeletal pain is an indicator of a complex patient who is at risk of poorer outcomes at the onset of new illnesses.

Extending methods for investigating the relationship between treatment effect and baseline risk from pairwise meta-analysis to network meta-analysis.

Baseline risk is a proxy for unmeasured but important patient-level characteristics, which may be modifiers of treatment effect, and is a potential source of heterogeneity in meta-analysis. Models adjusting for baseline risk have been developed for pairwise meta-analysis using the observed event rate in the placebo arm and taking into account the measurement error in the covariate to ensure that an unbiased estimate of the relationship is obtained. Our objective is to extend these methods to network meta-analysis where it is of interest to adjust for baseline imbalances in the non-intervention group event rate to reduce both heterogeneity and possibly inconsistency. This objective is complicated in network meta-analysis by this covariate being sometimes missing, because of the fact that not all studies in a network may have a non-active intervention arm. A random-effects meta-regression model allowing for inclusion of multi-arm trials and trials without a 'non-intervention' arm is developed. Analyses are conducted within a Bayesian framework using the WinBUGS software. The method is illustrated using two examples: (i) interventions to promote functional smoke alarm ownership by households with children and (ii) analgesics to reduce post-operative morphine consumption following a major surgery. The results showed no evidence of baseline effect in the smoke alarm example, but the analgesics example shows that the adjustment can greatly reduce heterogeneity and improve overall model fit.