Handling missing disease information due to death in diseases that need two visits to diagnose

In studies that assess disease status periodically, time of disease onset is interval censored between visits. Participants who die between two visits may have unknown disease status after their last visit. In this work, we consider an additional scenario where diagnosis requires two consecutive positive tests, such that disease status can also be unknown at the last visit preceding death. We show that this impacts the choice of censoring time for those who die without an observed disease diagnosis. We investigate two classes of models that quantify the effect of risk factors on disease outcome: a Cox proportional hazards model with death as a competing risk and an illness death model that treats disease as a possible intermediate state. We also consider four censoring strategies: participants without observed disease are censored at death (Cox model only), the last visit, the last visit with a negative test, or the second last visit. We evaluate the performance of model and censoring strategy combinations on simulated data with a binary risk factor and illustrate with a real data application. We find that the illness death model with censoring at the second last visit shows the best performance in all simulation settings. Other combinations show bias that varies in magnitude and direction depending on the differential mortality between diseased and disease-free subjects, the gap between visits, and the choice of the censoring time.

Associations between postoperative anaemia and unplanned readmission to hospital after major surgery: a retrospective cohort study†

BACKGROUND

Anaemia following major surgery may be associated with unplanned readmission to hospital. However, the severity-response relationship between the degree of anaemia at discharge and the risk of unplanned readmission is poorly defined. We aimed to describe the severity-response relationship between haemoglobin concentration at the time of discharge and the risk of unplanned readmission in a cohort of patients undergoing different types of major surgery.

METHODS

We performed a retrospective cohort study in a single tertiary health service, including all patients who underwent major surgery (orthopaedic, abdominal, cardiac or thoracic) between 1 May 2011 and 1 February 2022. The primary outcome was unplanned readmission to hospital in the 90 days following discharge after the index surgical procedure. These complex, non-linear relationships were modelled with restricted cubic splines.

RESULTS

We identified 22,134 patients and included 14,635 in the primary analysis, of whom 1804 (12%) experienced at least one unplanned readmission. The odds of unplanned readmission rose when the discharge haemoglobin concentration was < 100 g.l-1 (p < 0.001). On subgroup analysis, the haemoglobin threshold below which odds of readmission began to increase appeared to be higher in patients undergoing emergency surgery (110 g.l-1; p < 0.001) compared with elective surgery. Declining discharge haemoglobin concentration was associated with increased odds ratios (95%CI) of unplanned readmission in patients undergoing orthopaedic (1.08 (1.01-1.15), p = 0.03), abdominal (1.13 (1.07-1.19), p < 0.001) and thoracic (1.12 (1.01-1.24), p = 0.03) procedures, but not cardiac surgery (1.09 (0.99-1.19), p = 0.07).

CONCLUSIONS

Our findings suggest that a haemoglobin concentration < 100 g.l-1 following elective procedures and < 110 g.l-1 following emergency procedures, at the time of hospital discharge after major surgery, was associated with unplanned readmission. Future interventional trials that aim to treat postoperative anaemia and reduce unplanned readmission should include patients with discharge haemoglobin below these thresholds.

Advancing randomized controlled trial methodologies: The place of innovative trial design in eating disorders research

Randomized controlled trials can be used to generate evidence on the efficacy and safety of new treatments in eating disorders research. Many of the trials previously conducted in this area have been deemed to be of low quality, in part due to a number of practical constraints. This article provides an overview of established and more innovative clinical trial designs, accompanied by pertinent examples, to highlight how design choices can enhance flexibility and improve efficiency of both resource allocation and participant involvement. Trial designs include individually randomized, cluster randomized, and designs with randomizations at multiple time points and/or addressing several research questions (master protocol studies). Design features include the use of adaptations and considerations for pragmatic or registry-based trials. The appropriate choice of trial design, together with rigorous trial conduct, reporting and analysis, can establish high-quality evidence to advance knowledge in the field. It is anticipated that this article will provide a broad and contemporary introduction to trial designs and will help researchers make informed trial design choices for improved testing of new interventions in eating disorders. PUBLIC SIGNIFICANCE: There is a paucity of high quality randomized controlled trials that have been conducted in eating disorders, highlighting the need to identify where efficiency gains in trial design may be possible to advance the eating disorder research field. We provide an overview of some key trial designs and features which may offer solutions to practical constraints and increase trial efficiency.

Efficacy and safety of avatrombopag in combination with immunosuppressive therapy in treatment-naïve and relapsed/refractory severe aplastic anaemia: protocol for the DIAAMOND-Ava-FIRST and DIAAMOND-Ava-NEXT Bayesian Optimal Phase II trials

INTRODUCTION

Immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and ciclosporin is standard of care for patients with severe aplastic anaemia (sAA) not eligible or suitable for allogeneic stem cell transplant. While patients respond to IST, few achieve complete responses and a significant proportion are refractory or relapse. The addition of eltrombopag, a thrombopoietin-receptor agonist (TPO-A), to IST has been shown to improve haematological responses in sAA. Avatrombopag is a second-generation TPO-A with potential advantages over eltrombopag. However, to date avatrombopag has not been studied in sAA.

METHODS AND ANALYSIS

Investigator-initiated, single-arm registry-based Bayesian Optimal Phase II trial of avatrombopag conducted in two cohorts, patients with untreated sAA (FIRST cohort) and in patients with sAA that has relapsed or is refractory to IST (NEXT cohort). In the FIRST cohort, participants receive IST (equine ATG and ciclosporin) plus avatrombopag from day 1 until day 180 at 60 mg oral daily, with dose adjusted according to platelet count. Participants in the NEXT cohort receive avatrombopag at 60 mg oral daily from day 1 until day 180, with or without additional IST at the discretion of the treating clinician.For each cohort, two primary endpoints (haematological response and acquired clonal evolution) are jointly monitored and the trial reviewed at each interim analysis where a 'go/no-go' decision is made by evaluating the posterior probability of the events of interests.

ETHICS AND DISSEMINATION

The trial has received ethics approval (Monash Health RES-18-0000707A). The trial conduct will comply with ICH-GCP and all applicable regulatory requirements. The results of the trial will be submitted to a peer-review journal for publication.

TRIAL REGISTRATION NUMBER

ACTRN12619001042134, ACTRN12619001043123.

Metformin for knee osteoarthritis with obesity: study protocol for a randomised, double-blind, placebo-controlled trial

INTRODUCTION

Over half of the populations with knee osteoarthritis (OA) have obesity. These individuals have many other shared metabolic risk factors. Metformin is a safe, inexpensive, well-tolerated drug that has pleiotropic effects, including structural protection, anti-inflammatory and analgesic effects in OA, specifically the knee. The aim of this randomised, double-blind, placebo-controlled trial is to determine whether metformin reduces knee pain over 6 months in individuals with symptomatic knee OA who are overweight or obese.

METHODS AND ANALYSIS

One hundred and two participants with symptomatic knee OA and overweight or obesity will be recruited from the community in Melbourne, Australia, and randomly allocated in a 1:1 ratio to receive either metformin 2 g or identical placebo daily for 6 months. The primary outcome is reduction of knee pain [assessed by 100 mm Visual Analogue Scale (VAS)] at 6 months. The secondary outcomes are OMERACT-OARSI (Outcome Measures in Rheumatology-Osteoarthritis Research Society International) responder criteria [Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, function and participant's global assessment (VAS)] at 6 months; change in knee pain, stiffness, function using WOMAC at 6 months and quality of life at 6 months. Adverse events will be recorded. The primary analysis will be by intention to treat, including all participants in their randomised groups.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Alfred Hospital Ethics Committee (708/20) and Monash University Human Research Ethics Committee (28498). Written informed consent will be obtained from all the participants. The findings will be disseminated through peer-review publications and conference presentations.

TRIAL REGISTRATION NUMBER

ACTRN12621000710820 .

Negative back beliefs are associated with increased odds of low back pain and disability: a 10-year cohort study in men

OBJECTIVE

Although negative back beliefs are associated with high-intensity low back pain (LBP)/disability, whether they influence incident high-intensity LBP/high-disability over the long-term is unknown. This study aimed to investigate whether negative back beliefs were associated with developing high-intensity LBP and/or high-disability over 10 years in men.

METHODS

Men with no or low-intensity LBP and/or disability attending the Geelong Osteoporosis Study between 2006-2010 were included. Data on age, body mass index, mobility, education, back beliefs (Back Beliefs Questionnaire), LBP and disability (Graded Chronic Pain Scale) were collected between 2006-2010. Beliefs, LBP and disability were re-assessed in 2016-2021. Binary logistic regression was used to examine the association between negative back beliefs and incident high-intensity pain and/or high-disability, adjusting for age, body mass index, mobility, and education.

RESULTS

At baseline, 705 participants (mean age 53.8 years) had no or low LBP and no or low-disability; 441 (62.6%) participants completed a 10-year follow-up. Of these, 37 (8.4%) developed high-intensity pain and/or high-disability. In multivariate analyses, participants with more negative back beliefs at baseline were more likely to develop high-intensity pain and/or high-disability (Odds ratio 1.05, 95% CI 1.00-1.11). Developing more negative back beliefs was also associated with incident high-intensity pain and/or high-disability (Odds Ratio 1.20, 95% CI 1.12-1.30).

CONCLUSION

In a male community-based population, negative beliefs regarding the consequences of LBP were associated with an increased likelihood of developing high-intensity pain and/or high-disability. Addressing negative back beliefs in the community may reduce the incidence of high-intensity pain and/or high-disability over 10 years in men.

STAREE-Mind Imaging Study: a randomised placebo-controlled trial of atorvastatin for prevention of cerebrovascular decline and neurodegeneration in older individuals

Introduction

Cerebrovascular disease and neurodegeneration are causes of cognitive decline and dementia, for which primary prevention options are currently lacking. Statins are well-tolerated and widely available medications that potentially have neuroprotective effects. The STAREE-Mind Imaging Study is a randomised, double-blind, placebo-controlled clinical trial that will investigate the impact of atorvastatin on markers of neurovascular health and brain atrophy in a healthy, older population using MRI. This is a nested substudy of the 'Statins for Reducing Events in the Elderly' (STAREE) primary prevention trial.

Methods

Participants aged 70 years or older (n=340) will be randomised to atorvastatin or placebo. Comprehensive brain MRI assessment will be undertaken at baseline and up to 4 years follow-up, including structural, diffusion, perfusion and susceptibility imaging. The primary outcome measures will be change in brain free water fraction (a composite marker of vascular leakage, neuroinflammation and neurodegeneration) and white matter hyperintensity volume (small vessel disease). Secondary outcomes will include change in perivascular space volume (glymphatic drainage), cortical thickness, hippocampal volume, microbleeds and lacunae, prefrontal cerebral perfusion and white matter microstructure.

Ethics and dissemination

Academic publications from this work will address the current uncertainty regarding the impact of statins on brain structure and vascular integrity. This study will inform the utility of repurposing these well-tolerated, inexpensive and widely available drugs for primary prevention of neurological outcomes in older individuals. Ethics approval was given by Monash University Human Research Ethics Committee, Protocol 12206.

Trial registration number

ClinicalTrials.gov Identifier: NCT05586750.

Effect of 6-week treatment with topical betamethasone dipropionate in patients with symptomatic hand osteoarthritis: A randomized double-blind, placebo-controlled trial

Objective

To examine the efficacy and safety of topical corticosteroid over 6 weeks in patients with symptomatic hand osteoarthritis.

Design

In a randomized, double-blind, placebo-controlled trial, community-based participants with hand osteoarthritis were randomly assigned (1:1) to topical Diprosone OV (betamethasone dipropionate 0.5 ​mg/g in optimised vehicle, n=54) or placebo (plain paraffin, n=52) ointment to painful joints 3 times daily for 6 weeks. Primary outcome was pain reduction [assessed by 100 ​mm visual analogue scale (VAS)] at 6 weeks. Secondary outcomes included changes in pain and function using the Australian Canadian Osteoarthritis Hand Index (AUSCAN), Functional Index for Hand Osteoarthritis (FIHOA), and Michigan Hand Outcomes Questionnaire (MHQ) at 6 weeks. Adverse events were recorded.

Results

Of 106 participants (mean age 64.2 years, 85.9% female), 103 (97.2%) completed the study. Change in VAS at 6 weeks was similar in the Diprosone OV and placebo groups (-19.9 vs. -20.9, adjusted difference 0.6, 95% CI -8.9 to 10.2). There were no significant between-group differences in change in AUSCAN pain [adjusted difference 25.8 (-16.0 to 67.5)], AUSCAN function [21.2 (-55.0 to 97.4)], FIHOA [-0.1 (-1.7 to 1.5)], or MHQ [-1.2 (-6.0 to 3.6)]. Incidence of adverse events was 16.7% in Diprosone OV and 19.2% in placebo group.

Conclusions

Topical Diprosone OV ointment, although well-tolerated, was no better than placebo in improving pain or function over 6 weeks in patient with symptomatic hand osteoarthritis. Future studies should consider examining joints with synovitis and whether delivery approaches enhancing transdermal penetration of corticosteroids into joints are effective in hand osteoarthritis.

Trial registration

ACTRN 12620000599976. Registered May 22, 2020.

High levels of back disability, not back pain, are associated with reduced physical activity across key activity domains

BACKGROUND

Although remaining physically active is the cornerstone of management for low back pain, our understanding of the physical activity performed by those with back pain is limited.

OBJECTIVES

To examine the physical activity reported by individuals with different levels of low back pain and disability across key activity domains.

DESIGN

Community-based, cross-sectional study.

METHODS

542 women were recruited from a research database formed from an electoral roll and completed validated, self-report questionnaires. The amount and intensity of physical activity was reported using the International Physical Activity Questionnaire. Low back pain and disability were examined using the Graded Chronic Pain Scale. Participants were categorised into no, low or high pain and disability groups.

RESULTS

Individuals who reported high disability performed 55% of the physical activity of those without disability (MET(hours/week):median(95%CI) = 27.1(13.2-41.0); 48.8(37.8-59.9),p = 0.01), including less moderate (18.0(10.4-25.6); 31.0(24.0-38.1),p = 0.007), and domestic and gardening activity (14.7(7.2-22.3); 25.7(19.8-31.7),p = 0.001). Fewer women with high disability performed vigorous (OR(95%CI) = 0.29(0.13-0.65),p = 0.002) and leisure activities (0.17(0.04-0.75),p = 0.02) compared to those with no disability. Those with low disability reported less leisure activity ((0.55(0.35-0.88),p = 0.01), but more work-related activities and active transport than individuals without disability (1.65(1.01-2.7),p = 0.04; 1.6(1.04-2.6),p = 0.03). There were no differences in activity between pain groups, with the exception of those with low intensity pain performing less leisure activity (0.51(0.30-0.88),p = 0.01).

CONCLUSIONS

Individuals who reported high back disability, not back pain, were found to perform reduced physical activity, including less total, moderate, vigorous, and discretionary activity. These findings highlight the altered activity levels of people with back disability and the need to examine its impact on their health and wellbeing.

Use of a novel smartphone-based application tool for enrolment and randomisation in pre-hospital clinical trials

The effective recruitment and randomisation of patients in pre-hospital clinical trials presents unique challenges. Owing to the time critical nature of many pre-hospital emergencies and limited resourcing, the use of traditional methods of randomisation that may include centralised telephone or web-based systems are often not practicable or feasible. Previous technological limitations have necessitated that pre-hospital trialists strike a compromise between implementing pragmatic, deliverable study designs, and robust enrolment and randomisation methodologies. In this commentary piece, we present a novel smartphone-based solution that has the potential to align pre-hospital clinical trial recruitment processes to that of best-in-practice in-hospital and ambulatory care setting studies. Running title: Smartphone application based randomisation in pre-hospital clinical trials.

A Systematic Review of Joint Spatial and Spatiotemporal Models in Health Research

With the advancement of spatial analysis approaches, methodological research addressing the technical and statistical issues related to joint spatial and spatiotemporal models has increased. Despite the benefits of spatial modelling of several interrelated outcomes simultaneously, there has been no published systematic review on this topic, specifically when such models would be useful. This systematic review therefore aimed at reviewing health research published using joint spatial and spatiotemporal models. A systematic search of published studies that applied joint spatial and spatiotemporal models was performed using six electronic databases without geographic restriction. A search with the developed search terms yielded 4077 studies, from which 43 studies were included for the systematic review, including 15 studies focused on infectious diseases and 11 on cancer. Most of the studies (81.40%) were performed based on the Bayesian framework. Different joint spatial and spatiotemporal models were applied based on the nature of the data, population size, the incidence of outcomes, and assumptions. This review found that when the outcome is rare or the population is small, joint spatial and spatiotemporal models provide better performance by borrowing strength from related health outcomes which have a higher prevalence. A framework for the design, analysis, and reporting of such studies is also needed.

A protocol for a prospective, multicentre observational study to determine if nonanaemic iron deficiency worsens postoperative outcome in patients undergoing elective surgery for resection of colorectal cancer: The NATO study

BACKGROUND

Preoperative absolute and functional iron deficiency anaemia is associated with poor postoperative outcomes in patients undergoing surgery for colorectal cancer. It is biologically plausible that "early", or "nonanaemic" iron deficiency may also be associated with worse postoperative outcomes in similar cohorts, albeit at lesser severity than that seen for anaemia. The evidence supporting this assertion is of low quality.

METHODS

We have designed a prospective, observational study to delineate associations between preoperative non-anaemic iron deficiency and postoperative outcomes after surgery for colorectal cancer. Patients without anaemia, undergoing elective surgery for colorectal cancer will be allocated to an iron replete or an iron deficient group based on preoperative transferrin saturation. The primary outcome is days alive and at home on postoperative day 90. Secondary outcomes include days alive and at home on postoperative day 30, length of hospital stay, readmission to acute care, postoperative complications, health-related quality of life scores, quality of postoperative recovery, and requirement for allogeneic blood transfusion. The planned sample size is 422 patients, which has 80% power to detect a two-day difference in the primary outcome. The study commenced in May 2019.

CONCLUSION

The results of this study will provide patients and clinicians with high-quality evidence concerning associations between nonanaemic iron deficiency and patient-centred outcomes after surgery for colorectal cancer. The study will be conducted in multiple urban and rural centres across Australia and New Zealand. The results will be highly generalisable to contemporary surgical practice and should be rapidly translated.

Penalized likelihood estimation of the proportional hazards model for survival data with interval censoring

This paper considers the problem of semi-parametric proportional hazards model fitting where observed survival times contain event times and also interval, left and right censoring times. Although this is not a new topic, many existing methods suffer from poor computational performance. In this paper, we adopt a more versatile penalized likelihood method to estimate the baseline hazard and the regression coefficients simultaneously. The baseline hazard is approximated using basis functions such as M-splines. A penalty is introduced to regularize the baseline hazard estimate and also to ease dependence of the estimates on the knots of the basis functions. We propose a Newton-MI (multiplicative iterative) algorithm to fit this model. We also present novel asymptotic properties of our estimates, allowing for the possibility that some parameters of the approximate baseline hazard may lie on the parameter space boundary. Comparisons of our method against other similar approaches are made through an intensive simulation study. Results demonstrate that our method is very stable and encounters virtually no numerical issues. A real data application involving melanoma recurrence is presented and an R package 'survivalMPL' implementing the method is available on R CRAN.

Platform trials for anaesthesia and perioperative medicine: a narrative review

Large randomised trials provide the most reliable evidence of effectiveness of new treatments in clinical practice. However, the time and resources required to complete such trials can be daunting. An overarching clinical trial platform focused on a single condition or type of surgery, aiming to compare several treatments, with an option to stop any or add in new treatment options, can provide greater efficiency. This has the potential to accelerate knowledge acquisition and identify effective, ineffective, or harmful treatments faster. The master protocol of the platform defines the study population(s) and standardised procedures. Ineffective or harmful treatments can be discarded or study drug dose modified during the life cycle of the trial. Other adaptive elements that can be modified include eligibility criteria, required sample size for any comparison(s), randomisation assignment ratio, and the addition of other promising treatment options. There are excellent opportunities for anaesthetists to establish platform trials in perioperative medicine. Platform trials are highly efficient, with the potential to provide quicker answers to important clinical questions that lead to improved patient care.

Examining evidence of time-dependent treatment effects: an illustration using regression methods

BACKGROUND

For the design and analysis of clinical trials with time-to-event outcomes, the Cox proportional hazards model and the logrank test have been the cornerstone methods for many decades. Increasingly, the key assumption of proportionality-or time-fixed effects-that underpins these methods has been called into question. The availability of novel therapies with new mechanisms of action and clinical trials of longer duration mean that non-proportional hazards are now more frequently encountered.

METHODS

We compared several regression-based methods to model time-dependent treatment effects. For illustration purposes, we used selected endpoints from a large, community-based clinical trial of low dose daily aspirin in older persons. Relative and absolute estimands were defined, and analyses were conducted in all participants. Additional exploratory analyses were undertaken by selected subgroups of interest using interaction terms in the regression models.

DISCUSSION

In the trial with median 4.7 years follow-up, we found evidence for non-proportionality and a time-dependent treatment effect of aspirin on cancer mortality not previously reported in trial findings. We also found some evidence of time-dependence to an aspirin by age interaction for major adverse cardiovascular events. For other endpoints, time-fixed treatment effect estimates were confirmed as appropriate.

CONCLUSIONS

The consideration of treatment effects using both absolute and relative estimands enhanced clinical insights into potential dynamic treatment effects. We recommend these analytical approaches as an adjunct to primary analyses to fully explore findings from clinical trials.

Bayesian adaptive clinical trial designs for respiratory medicine

The use of Bayesian adaptive designs for clinical trials has increased in recent years, particularly during the COVID‐19 pandemic. Bayesian adaptive designs offer a flexible and efficient framework for conducting clinical trials and may provide results that are more useful and natural to interpret for clinicians, compared to traditional approaches. In this review, we provide an introduction to Bayesian adaptive designs and discuss its use in recent clinical trials conducted in respiratory medicine. We illustrate this approach by constructing a Bayesian adaptive design for a multi‐arm trial that compares two non‐invasive ventilation treatments to standard oxygen therapy for patients with acute cardiogenic pulmonary oedema. We highlight the benefits and some of the challenges involved in designing and implementing Bayesian adaptive trials.

A biomarker-guided Bayesian response-adaptive phase II trial for metastatic melanoma: The Personalized Immunotherapy Platform (PIP) trial design

TPS9599

Background: Anti-PD1-based immunotherapies have been approved for many cancer types and are now a standard therapy for advanced melanoma. Despite this, ̃50% of advanced melanoma patients (pts) fail to respond or eventually progress after response. It is therefore critical to identify pts with a low likelihood of response to anti-PD1-based therapy and efficiently assess activity of rationally-selected alternative novel immunotherapies. Methods: We designed this investigator-initiated phase II PIP-Trial to evaluate two consecutive biomarker testing platforms, followed by the activity of rationally selected 5 novel agents in pts with advanced melanoma. Two separate pt populations are included: Part-A) treatment-naïve pts predicted to be resistant to either anti-PD-1 alone or combined with ipilimumab using Biomarker Test-1); and Part-B) pts who had progressed on 1 prior line of PD1-based therapy. Part-A) is a Bayesian adaptive multi-arm multi-stage design using response adaptive randomisation after a burn-in period where pts are randomised to the existing arms with equal probability. From then on, regular interim analyses will be carried out with the objective to either drop poorly performing arms or continue. Part-B) is an open platform without control that combined a selection and an expansion phase to identify best novel agent(s) as second-line therapy. Expansion phase decisions will be based on enrichment for biomarker Test-2. Dropping an arm occurs when the posterior probability of observing a clinically significant effect on the primary outcome (i.e. 6-month RECIST objective response rate (ORR)) is low. The operational characteristics of the design were investigated through simulations considering 4 plausible scenarios with 40% ORR in the control arm (anti-PD1 + Anti-CTLA4). Simulations were based on the upcoming R package BATS. Part-A has at least 85% power to detect a 30% absolute improvement in ORR with respect to the control arm (with a max N = 216 – Table below). Part-B will be able to select two promising treatments in the expansion phase and formally test their efficacy against a minimum ORR of 25% at 80% power (max N = 150). [Table: see text]

Evaluating the performance of Bayesian and restricted maximum likelihood estimation for stepped wedge cluster randomized trials with a small number of clusters

Background

Stepped wedge trials are an appealing and potentially powerful cluster randomized trial design. However, they are frequently implemented with a small number of clusters. Standard analysis methods for these trials such as a linear mixed model with estimation via maximum likelihood or restricted maximum likelihood (REML) rely on asymptotic properties and have been shown to yield inflated type I error when applied to studies with a small number of clusters. Small-sample methods such as the Kenward-Roger approximation in combination with REML can potentially improve estimation of the fixed effects such as the treatment effect. A Bayesian approach may also be promising for such multilevel models but has not yet seen much application in cluster randomized trials.

Methods

We conducted a simulation study comparing the performance of REML with and without a Kenward-Roger approximation to a Bayesian approach using weakly informative prior distributions on the intracluster correlation parameters. We considered a continuous outcome and a range of stepped wedge trial configurations with between 4 and 40 clusters. To assess method performance we calculated bias and mean squared error for the treatment effect and correlation parameters and the coverage of 95% confidence/credible intervals and relative percent error in model-based standard error for the treatment effect.

Results

Both REML with a Kenward-Roger standard error and degrees of freedom correction and the Bayesian method performed similarly well for the estimation of the treatment effect, while intracluster correlation parameter estimates obtained via the Bayesian method were less variable than REML estimates with different relative levels of bias.

Conclusions

The use of REML with a Kenward-Roger approximation may be sufficient for the analysis of stepped wedge cluster randomized trials with a small number of clusters. However, a Bayesian approach with weakly informative prior distributions on the intracluster correlation parameters offers a viable alternative, particularly when there is interest in the probability-based inferences permitted within this paradigm.

Supplementary Information

The online version contains supplementary material available at (10.1186/s12874-022-01550-8).

A protocol for prospective observational study to determine if non-anaemic iron deficiency worsens postoperative outcome in adult patients undergoing elective cardiac surgery: the IDOCS study

Background

Pre-operative anaemia has been associated independently with worse outcomes after cardiac surgery in adults and is often caused by absolute or functional iron deficiency. Iron deficiency is a continuum ending with anaemia, and therefore it is plausible that pre-operative early or ‘non-anaemic’ iron deficiency may also be associated with worse outcomes in patients undergoing cardiac surgery.

Methods

We have designed a prospective, observational study to determine if there is an association between non-anaemic iron deficiency and worse outcomes after cardiac surgery in adults. Patients without anaemia undergoing elective cardiac surgery will be allocated to an iron-deficient and an iron-replete group based on standard pre-operative blood tests (ferritin, transferrin saturation and C-reactive protein). The primary outcome is days alive and at home on postoperative day 30. The key secondary outcomes are days alive and at home on postoperative day 90 and readmission to acute care. Other secondary outcomes include health-related quality of life questionnaires, quality of postoperative recovery, postoperative complications, changes in haemoglobin concentration, and requirement for allogeneic blood products. The planned study sample size is 240 patients per group, which has 83% power to detect a median difference of 1.25 days in the primary outcome. The study commenced in March 2018, and recently completed recruitment, with data audit and cleaning ongoing.

Discussion

This study will be conducted using a rigorous, prospective observational design; it will provide peak bodies and clinicians with high-quality evidence concerning the associations between non-anaemic iron deficiency and patient-centred outcomes after elective cardiac surgery. Our primary and key secondary outcomes are known to have great importance to clinicians and patients alike and align with the recommendations of the StEP-COMPAC group for outcomes in prospective peri-operative research. The definition used for iron deficiency accounts for both absolute and functional iron deficiency and make use of standard pre-operative blood tests to make this determination, easing the transition of results into clinical practice. The study will be conducted in two relatively high-volume centres in a single high-income country. This limits the generalisability of study results to similar centres.

Trial registration

Australian and New Zealand Clinical Trials Registry (ACTRN12618000185268). Registered 5 February 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13741-022-00239-2.

Topical corticosteroid for treatment of hand osteoarthritis: study protocol for a randomised controlled trial

Background

Hand osteoarthritis is a common and disabling chronic joint disease with a lack of effective therapies. Emerging evidence suggests the role of local inflammation in causing pain in hand osteoarthritis. Corticosteroids are potent anti-inflammatory drugs used in many rheumatic diseases. The aim of this randomised, double-blind, placebo-controlled trial is to determine whether topical corticosteroid reduces pain over 6 weeks in patients with hand osteoarthritis.

Methods

One hundred participants with hand osteoarthritis will be recruited from the community in Melbourne, Australia, and randomly allocated in a 1:1 ratio to receive either topical Diprosone OV or placebo ointment administered 3 times daily on the painful hand joints for 6 weeks. The primary outcome is pain reduction (assessed by 100 mm visual analogue scale) at 6 weeks. The secondary outcomes include changes in pain and function assessed using Functional Index for Hand Osteoarthritis, Australian Canadian Osteoarthritis Hand Index, Michigan Hand Outcomes Questionnaire, and tender and swollen joint count at 6 weeks. Adverse events will be recorded. The primary analysis will be by intention to treat, including all participants in their randomised groups.

Discussion

This study will provide high-quality evidence to determine whether topical corticosteroid reduces pain over 6 weeks in patients with hand osteoarthritis, with major clinical and public health importance by informing clinical practice guidelines for the management of hand osteoarthritis and reducing the burden of the disabling disease.

Trial registration

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12620000599976. Registered 22 May 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04921-2.

Rationale and design of the intravenous iron for treatment of anemia before cardiac surgery trial

Background Approximately 20% to 30% of patients awaiting cardiac surgery are anemic. Anemia increases the likelihood of requiring a red cell transfusion and is associated with increased complications, intensive care, and hospital stay following surgery. Iron deficiency is the commonest cause of anemia and preoperative intravenous (IV) iron therapy thus may improve anemia and therefore patient outcome following cardiac surgery. We have initiated the intravenous iron for treatment of anemia before cardiac surgery (ITACS) Trial to test the hypothesis that in patients with anemia awaiting elective cardiac surgery, IV iron will reduce complications, and facilitate recovery after surgery. Methods ITACS is a 1,000 patient, international randomized trial in patients with anemia undergoing elective cardiac surgery. The patients, health care providers, data collectors, and statistician are blinded to whether patients receive IV iron 1,000 mg, or placebo, at 1-26 weeks before their planned date of surgery. The primary endpoint is the number of days alive and at home up to 90 days after surgery. Results To date, ITACS has enrolled 615 patients in 30 hospitals in 9 countries. Patient mean (SD) age is 66 (12) years, 63% are male, with a mean (SD) hemoglobin at baseline of 118 (12) g/L; 40% have evidence (ferritin <100 ng/mL and/or transferrin saturation <25%) suggestive of iron deficiency. Most (59%) patients have undergone coronary artery surgery with or without valve surgery. Conclusions The ITACS Trial will be the largest study yet conducted to ascertain the benefits and risks of IV iron administration in anemic patients awaiting cardiac surgery.

707High levels of back disability,but not back pain,are associated with reduced physical activity in women

Background

Although clinical guidelines recommend physical activity for low back pain (LBP), our understanding of the physical activity undertaken by people with LBP is limited. We examined the amounts, intensities and types of physical activity performed by community-based women with different levels of pain and disability.

Methods

542 women were invited to participate. Physical activity was measured using the International Physical Activity Questionnaire, and LBP and disability were assessed using the Chronic Pain Grade Questionnaire. Participants were categorised into no/low or high pain intensity and disability groups.

Results

Women with high levels of back disability performed half the total physical activity of those with no/low levels of back disability (MET(hours/week): median(95%CI)=27.3(13.2-41.4) vs. 53.9(44.9-62.8),p=0.002), including less moderate (17.5(10.4-24.7) vs. 32.1(26.8-37.4),p&lt;0.001) and domestic and gardening activity (14.4(7.2- 21.7) vs. 23.5(19.0-28.0), p = 0.02). Moreover, fewer women with high disability participated in vigorous (3(8.11%) vs. 134(32.0%),OR(95%CI)=0.17(0.04-0.75),p=0.02) and leisure activities (17(45.9%) vs. 294(70.2%),OR(95% CI)=0.44(0.21-0.94),p=0.03) compared to those with no/low disability. There were no differences in physical activity between women with no/low and high pain intensity (all p &gt; 0.05).

Conclusions

High levels of back disability, but not back pain intensity, were associated with reduced physical activity, including less total activity, moderate and vigorous intense activity, and discretionary activity.

Key messages

These findings highlight the impact of high levels of disability on physical activity. Further work is needed to determine whether targeting these types and intensities of physical activity will help in reducing back disability.

Impact of a non-constant baseline hazard on detection of time-dependent treatment effects: a simulation study

Background

Non-proportional hazards are common with time-to-event data but the majority of randomised clinical trials (RCTs) are designed and analysed using approaches which assume the treatment effect follows proportional hazards (PH). Recent advances in oncology treatments have identified two forms of non-PH of particular importance - a time lag until treatment becomes effective, and an early effect of treatment that ceases after a period of time. In sample size calculations for treatment effects on time-to-event outcomes where information is based on the number of events rather than the number of participants, there is crucial importance in correct specification of the baseline hazard rate amongst other considerations. Under PH, the shape of the baseline hazard has no effect on the resultant power and magnitude of treatment effects using standard analytical approaches. However, in a non-PH context the appropriateness of analytical approaches can depend on the shape of the underlying hazard.

Methods

A simulation study was undertaken to assess the impact of clinically plausible non-constant baseline hazard rates on the power, magnitude and coverage of commonly utilized regression-based measures of treatment effect and tests of survival curve difference for these two forms of non-PH used in RCTs with time-to-event outcomes.

Results

In the presence of even mild departures from PH, the power, average treatment effect size and coverage were adversely affected. Depending on the nature of the non-proportionality, non-constant event rates could further exacerbate or somewhat ameliorate the losses in power, treatment effect magnitude and coverage observed. No single summary measure of treatment effect was able to adequately describe the full extent of a potentially time-limited treatment benefit whilst maintaining power at nominal levels.

Conclusions

Our results show the increased importance of considering plausible potentially non-constant event rates when non-proportionality of treatment effects could be anticipated. In planning clinical trials with the potential for non-PH, even modest departures from an assumed constant baseline hazard could appreciably impact the power to detect treatment effects depending on the nature of the non-PH. Comprehensive analysis plans may be required to accommodate the description of time-dependent treatment effects.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-021-01372-0.

Why do strategies to strengthen primary health care succeed in some places and fail in others? Exploring local variation in the effectiveness of a community health worker managed digital health intervention in rural India

Introduction

Digital health interventions (DHIs) have huge potential as support modalities to identify and manage cardiovascular disease (CVD) risk in resource-constrained settings, but studies assessing them show modest effects. This study aims to identify variation in outcomes and implementation of SMARTHealth India, a cluster randomised trial of an ASHA-managed digitally enabled primary healthcare (PHC) service strengthening strategy for CVD risk management, and to explain how and in what contexts the intervention was effective.

Methods

We analysed trial outcome and implementation data for 18 PHC centres and collected qualitative data via focus groups with ASHAs (n=14) and interviews with ASHAs, PHC facility doctors and fieldteam mangers (n=12) Drawing on principles of realist evaluation and an explanatory mixed-methods design we developed mechanism-based explanations for observed outcomes.

Results

There was substantial between-cluster variation in the primary outcome (overall: I²=62.4%, p<=0.001). The observed heterogeneity in trial outcomes was not attributable to any single factor. Key mechanisms for intervention effectiveness were community trust and acceptability of doctors’ and ASHAs’ new roles, and risk awareness. Enabling local contexts were seen to evolve over time and in response to the intervention. These included obtaining legitimacy for ASHAs’ new roles from trusted providers of curative care; ASHAs’ connections to community and to qualified providers; their responsiveness to community needs; and the accessibility, quality and appropriateness of care provided by higher level medical providers, including those outside of the implementing (public) subsystem.

Conclusion

Local contextual factors were significant influences on the effectiveness of this DHI-enabled PHC service strategy intervention. Local adaptions need to be planned for, monitored and responded to over time. By identifying plausible explanations for variation in outcomes between clusters, we identify potential strategies to strengthen such interventions.

Impact of age at type 2 diabetes mellitus diagnosis on mortality and vascular complications: systematic review and meta-analyses

AIMS/HYPOTHESIS

Few studies examine the association between age at diagnosis and subsequent complications from type 2 diabetes. This paper aims to summarise the risk of mortality, macrovascular complications and microvascular complications associated with age at diagnosis of type 2 diabetes.

METHODS

Data were sourced from MEDLINE and All EBM (Evidence Based Medicine) databases from inception to July 2018. Observational studies, investigating the effect of age at diabetes diagnosis on macrovascular and microvascular diabetes complications in adults with type 2 diabetes were selected according to pre-specified criteria. Two investigators independently extracted data and evaluated all studies. If data were not reported in a comparable format, data were obtained from authors, presented as minimally adjusted ORs (and 95% CIs) per 1 year increase in age at diabetes diagnosis, adjusted for current age for each outcome of interest. The study protocol was recorded with PROSPERO International Prospective Register of Systematic Reviews (CRD42016043593).

RESULTS

Data from 26 observational studies comprising 1,325,493 individuals from 30 countries were included. Random-effects meta-analyses with inverse variance weighting were used to obtain the pooled ORs. Age at diabetes diagnosis was inversely associated with risk of all-cause mortality and macrovascular and microvascular disease (all p < 0.001). Each 1 year increase in age at diabetes diagnosis was associated with a 4%, 3% and 5% decreased risk of all-cause mortality, macrovascular disease and microvascular disease, respectively, adjusted for current age. The effects were consistent for the individual components of the composite outcomes (all p < 0.001).

CONCLUSIONS/INTERPRETATION

Younger, rather than older, age at diabetes diagnosis was associated with higher risk of mortality and vascular disease. Early and sustained interventions to delay type 2 diabetes onset and improve blood glucose levels and cardiovascular risk profiles of those already diagnosed are essential to reduce morbidity and mortality. Graphical abstract.

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial

IMPORTANCE

Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited.

OBJECTIVE

To determine whether hydrocortisone improves outcome for patients with severe COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020.

INTERVENTIONS

The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108).

MAIN OUTCOMES AND MEASURES

The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%).

RESULTS

After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively.

CONCLUSIONS AND RELEVANCE

Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02735707.

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial

IMPORTANCE

Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited.

OBJECTIVE

To determine whether hydrocortisone improves outcome for patients with severe COVID-19.

DESIGN, SETTING, AND PARTICIPANTS

An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020.

INTERVENTIONS

The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108).

MAIN OUTCOMES AND MEASURES

The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%).

RESULTS

After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively.

CONCLUSIONS AND RELEVANCE

Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02735707.

Effective rescue treatment with vemurafenib of an infant with high-risk Langerhans cell histiocytosis

INTRODUCTION

The recently identified role of a BRAF somatic mutation in the pathophysiology of Langerhans cell histiocytosis (LCH) offers new therapeutic options. Herein we describe the case of a 10-month-old infant with refractory high-risk LCH successfully treated with vemurafenib.

OBSERVATION

The patient first presented with cutaneous LCH at the age of 2 months. The disease remained undiagnosed until she was 6 months old, when it rapidly evolved to a multisystemic high-risk and life-threatening disease, refractory to 2 lines of chemotherapy. BRAFV600E mutation was found at skin biopsy, and targeted therapy with vemurafenib was started when she was 10 months old. The treatment induced a fast and sustained response, but rapid relapse occurred after treatment discontinuation, leading to resumption of treatment, once more resulting in a sustained response.

CONCLUSION

Our case highlights the first-line role of dermatologists in establishing the diagnosis of LCH, especially in children, in whom the eruption may be difficult to identify, leading to delayed diagnosis. Targeted therapy with vemurafenib has recently been described in children in this indication and our results support its efficacy, highlighting the need for prolonged treatment and raising the question of maintenance therapy, as well as the necessity for large-scale and long-term studies.

Catastrophization, fear of movement, anxiety, and depression are associated with persistent, severe low back pain and disability

BACKGROUND CONTEXT

Psychological characteristics are important in the development and progression of low back pain (LBP); however, their role in persistent, severe LBP is unclear.

PURPOSE

To investigate the relationship between catastrophization, depression, fear of movement, and anxiety and persistent, severe LBP, and disability.

STUDY DESIGN/ SETTING

One-year prospective cohort study.

PATIENT SAMPLE

Participants were selected from the SpineData registry (Denmark), which enrolls individuals with LBP of 2 to 12 months duration without radiculopathy and without satisfactory response to primary intervention.

OUTCOME MEASURES

Psychological characteristics, including catastrophization, depression, fear of movement, and anxiety, were examined at baseline using a validated screening questionnaire. Current, typical, and worst pain in the past 2 weeks were assessed by 11-point numeric rating scales and an average pain score was calculated. Disability was measured using the 23-item Roland-Morris Disability Questionnaire.

METHODS

Participants completed baseline questionnaires on initial presentation to the Spine Center (Middelfart, Denmark), and follow-up questionnaires were sent and returned electronically. Statistical analysis involved multivariable Poisson regression to investigate the association between psychological factors and the number of episodes of severe pain or disability. This study received no direct funding.

RESULTS

Of the 952 participants at baseline, 633 (63.4%) provided data 1 year later. Approximately half of the participants reported severe LBP (n=299, 47.2%, 95% confidence interval [CI] 43.3%-51.2%) or disability (n=315, 57.6%, 95% CI 53.3%-61.8%) at a minimum of one time point, and 14.9% (n=94, 95% CI 12.2%-17.9%) and 24.3% (n=133, 95% CI 20.8%-28.1%) experienced severe LBP or disability at two time points, respectively. Multivariable Poisson regression showed a relationship between catastrophization, depression, fear of movement, and anxiety and a greater number of time points with severe LBP and disability, after adjusting for age, gender, body mass index, and duration of symptoms. However, when all psychological factors were added to the regression model, only catastrophization and depression remained significantly associated.

CONCLUSIONS

This study showed that persistent, severe LBP, and disability is common in a secondary care population with LBP and is associated with a variety of psychological risk factors, in particular catastrophization and depression, highlighting the importance of considering these factors in the design and evaluation of outcomes studies for LBP.

Development, Relative Validity and Reproducibility of the Aus-SDS (Australian Short Dietary Screener) in Adults Aged 70 Years and Above

The aim of this study was to assess the relative validity and reproducibility of a six-item Australian Short Dietary Screener (Aus-SDS). The Aus-SDS assessed the daily intake of core food groups (vegetables, fruits, legumes and beans, cereals, protein sources and dairy sources) in 100 Australians (52 males and 48 females) aged ≥70 years. Relative validity was assessed by comparing intakes from the Aus-SDS1 with an average of three 24-hour recalls (24-HRs), and reproducibility using two administrations of the Aus-SDS (Aus-SDS1 and Aus-SDS2). Cohen's kappa statistic between the Aus-SDS1 and 24-HRs showed moderate to good agreement, ranging from 0.44 for fruits and dairy to 0.64 for protein. There was poor agreement for legume intake (0.12). Bland-Altman plots demonstrated acceptable limits of agreement between the Aus-SDS1 and 24-HRs for all food groups. Median intakes obtained from Aus-SDS1 and Aus-SDS2 did not differ. For all food groups, Cohen's kappa statistic ranged from 0.68 to 0.89, indicating acceptable agreement between the Aus-SDS1 and Aus-SDS2. Spearman's correlation coefficient between Aus-SDS1 and 24-HRs across all food groups ranged from 0.64 for fruit to 0.83 for protein. We found the Aus-SDS to be a useful tool in assessing daily intake of core food groups in this population.

Digitally enabled aged care and neurological rehabilitation to enhance outcomes with Activity and MObility UsiNg Technology (AMOUNT) in Australia: A randomised controlled trial

BACKGROUND

Digitally enabled rehabilitation may lead to better outcomes but has not been tested in large pragmatic trials. We aimed to evaluate a tailored prescription of affordable digital devices in addition to usual care for people with mobility limitations admitted to aged care and neurological rehabilitation.

METHODS AND FINDINGS

We conducted a pragmatic, outcome-assessor-blinded, parallel-group randomised trial in 3 Australian hospitals in Sydney and Adelaide recruiting adults 18 to 101 years old with mobility limitations undertaking aged care and neurological inpatient rehabilitation. Both the intervention and control groups received usual multidisciplinary inpatient and post-hospital rehabilitation care as determined by the treating rehabilitation clinicians. In addition to usual care, the intervention group used devices to target mobility and physical activity problems, individually prescribed by a physiotherapist according to an intervention protocol, including virtual reality video games, activity monitors, and handheld computer devices for 6 months in hospital and at home. Co-primary outcomes were mobility (performance-based Short Physical Performance Battery [SPPB]; continuous version; range 0 to 3; higher score indicates better mobility) and upright time as a proxy measure of physical activity (proportion of the day upright measured with activPAL) at 6 months. The dataset was analysed using intention-to-treat principles. The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12614000936628). Between 22 September 2014 and 10 November 2016, 300 patients (mean age 74 years, SD 14; 50% female; 54% neurological condition causing activity limitation) were randomly assigned to intervention (n = 149) or control (n = 151) using a secure online database (REDCap) to achieve allocation concealment. Six-month assessments were completed by 258 participants (129 intervention, 129 control). Intervention participants received on average 12 (SD 11) supervised inpatient sessions using 4 (SD 1) different devices and 15 (SD 5) physiotherapy contacts supporting device use after hospital discharge. Changes in mobility scores were higher in the intervention group compared to the control group from baseline (SPPB [continuous, 0-3] mean [SD]: intervention group, 1.5 [0.7]; control group, 1.5 [0.8]) to 6 months (SPPB [continuous, 0-3] mean [SD]: intervention group, 2.3 [0.6]; control group, 2.1 [0.8]; mean between-group difference 0.2 points, 95% CI 0.1 to 0.3; p = 0.006). However, there was no evidence of a difference between groups for upright time at 6 months (mean [SD] proportion of the day spent upright at 6 months: intervention group, 18.2 [9.8]; control group, 18.4 [10.2]; mean between-group difference -0.2, 95% CI -2.7 to 2.3; p = 0.87). Scores were higher in the intervention group compared to the control group across most secondary mobility outcomes, but there was no evidence of a difference between groups for most other secondary outcomes including self-reported balance confidence and quality of life. No adverse events were reported in the intervention group. Thirteen participants died while in the trial (intervention group: 9; control group: 4) due to unrelated causes, and there was no evidence of a difference between groups in fall rates (unadjusted incidence rate ratio 1.19, 95% CI 0.78 to 1.83; p = 0.43). Study limitations include 15%-19% loss to follow-up at 6 months on the co-primary outcomes, as anticipated; the number of secondary outcome measures in our trial, which may increase the risk of a type I error; and potential low statistical power to demonstrate significant between-group differences on important secondary patient-reported outcomes.

CONCLUSIONS

In this study, we observed improved mobility in people with a wide range of health conditions making use of digitally enabled rehabilitation, whereas time spent upright was not impacted.

TRIAL REGISTRATION

The trial was prospectively registered with the Australian New Zealand Clinical Trials Register; ACTRN12614000936628.

How many times should a cluster randomized crossover trial cross over?

Trial planning requires making efficient yet practical design choices. In a cluster randomized crossover trial, clusters of subjects cross back and forth between implementing the control and intervention conditions over the course of the trial, with each crossover marking the start of a new period. If it is possible to set up such a trial with more crossovers, a pertinent question is whether there are efficiency gains from clusters crossing over more frequently, and if these gains are substantial enough to justify the added complexity and cost of implementing more crossovers. We seek to determine the optimal number of crossovers for a fixed trial duration, and then identify other highly efficient designs by allowing the total number of clusters to vary and imposing thresholds on maximum cost and minimum statistical power. Our results pertain to trials with continuous recruitment and a continuous primary outcome, with the treatment effect estimated using a linear mixed model. To account for the similarity between subjects' outcomes within a cluster, we assume a correlation structure in which the correlation decays gradually in a continuous manner as the time between subjects' measurements increases. The optimal design is characterized by crossovers between the control and intervention conditions with each successive subject. However, this design is neither practical nor cost-efficient to implement, nor is it necessary: the gains in efficiency increase sharply in moving from a two-period to a four-period trial design, but approach an asymptote for the scenarios considered as the number of crossovers continues to increase.

Association between Dietary Intake and Lipid-Lowering Therapy: Prospective Analysis of Data from Australian Diabetes, Obesity, and Lifestyle Study (AusDiab) Using a Quantile Regression Approach

Lipid-lowering therapy (LLT) should be accompanied by dietary guidance for cardiovascular risk reduction; however, current evidence suggests sub-optimal dietary behaviors in those on LLT. We examined the associations between the dietary intake of key food groups (vegetables, fruit, cereal, protein, and dairy) and LLT use in Australian adults using quantile regression. We used data from the Australian Diabetes, Obesity and Lifestyle Study (AusDiab), a prospective population-based study of adults aged ≥25 years, conducted over 5 years (1999-2005). Measurements included a 121-item food frequency questionnaire and LLT use. LLT use was categorized as: LLT users (n = 446), commenced LLT (n = 565), ceased LLT (n = 71), and non-users (n = 4813). Less than 1% of the cohort met recommended intakes of all food groups at the baseline and follow up. The median daily dietary intake at the follow up among LLT users was 2.2 serves of vegetables, 1.4 serves of fruit, 2.8 serves of cereal, 2.0 serves of protein, and 1.4 serves of dairy. Adjusted analysis showed no differences across the quantiles of intake of key food groups in LLT users and commenced LLT compared to non-users. The LLT medication status is not associated with any difference in meeting recommended intakes of key foods.

Prescriptions et usages de prégabaline : analyse d’une cohorte de 419 patients en centre d’étude et de traitement de la douleur et revue de la littérature

Du fait de l’augmentation du nombre de prescription de prégabaline dans le domaine de la douleur chronique et de cas relevés de mésusage récréatif ou toxicomaniaque avec ce médicament dans le monde, dans le contexte de la crise sanitaire en cours avec l’usage des opioïdes aux États-Unis, la crainte d’un risque addictif directement lié à l’usage de cette molécule a incité les autorités de divers pays à une surveillance accrue. Les recueils effectués par les centres de pharmacovigilance concernant la prégabaline relevant avant tout les situations considérées comme anormales, la description de l’usage de cette molécule au quotidien par un ensemble de prescripteurs et d’utilisateurs durant une période prolongée reflète mieux les conditions naturelles d’emploi de cette molécule et permet d’identifier les divers types de comportements des professionnels et usagers de santé à son égard. Une analyse rétrospective des dossiers de patients utilisateurs de prégabaline reçus et suivis dans une structure d’évaluation et prise en charge de la douleur pendant six ans a été réalisée, comprenant des données précises concernant les conditions d’usage et les effets du médicament. Les données issues de la littérature internationale et celles issues de l’étude montrent que le risque de mésusage et addictif est faible dans un contexte de prescription antalgique et de suivi médical adéquat, alors qu’il est élevé et directement lié à un mésusage de type récréatif ou toxicomaniaque en association avec les opioïdes ou l’alcool, en particulier dans la population jeune et en dehors du milieu des soins. Des recommandations d’usage de la prégabaline sont proposées aux professionnels afin de rappeler ces facteurs de risque.

Association Between Dietary Intake and Lipid-lowering Therapy: Prospective Analysis Using a Quantile Regression Approach (OR22-03-19)

Objectives

Lipid-lowering therapy (LLT) is ideally accompanied by dietary guidance for cardiovascular risk reduction, however current evidence suggests sub optimal dietary behaviours in those on pharmacological interventions. This study examines associations between daily intake of major food groups (vegetable, fruit, cereal, protein and dairy) and LLT use in Australian adults.

Methods

Data were analysed from 5895 participants of the Australian Diabetes, Obesity and Lifestyle Study (AusDiab) aged ≥ 25 years. Medical history and dietary intake was obtained at baseline (1999–00) and follow up (2004–05). LLT use was categorised as: LLT users, commenced LLT, ceased LLT, and non-users. The association between dietary intake and LLT use was examined using quantile regression, at the 25th, 50th and 75th quantile of dietary intake. Analysis was adjusted for known risk factors.

Results

A total of 446 participants remained on LLT from baseline to follow up; 565 participants commenced LLT; 71 participants ceased LLT and 4813 were non-users. Less than 1% of the cohort met recommended intakes of all food groups at baseline and follow up, with no difference by LLT status. Median daily dietary intake at follow up among LLT users was 2.2 serves of vegetables, 1.4 serves of fruit, 2.8 serves of cereal, 2.0 serves of protein and 1.4 serves of dairy. Dietary intake was similar across all LLT groups. LLT use was not significantly associated with dietary intake at the 25th, 50th and 75th quantile.

Conclusions

Adjusted quantile regression analysis showed no differences in median daily intake of key food groups in LLT users, compared to non-users. The dietary behaviours observed suggest that all adults, regardless of their medication regimen, need additional education on improving their dietary intake. These findings emphasise the importance of addressing adherence to dietary guidelines, for people with chronic disease, with special focus on people requiring LLT.

Funding Sources

Nil

Supporting Tables, Images and/or Graphs

Are non-constant rates and non-proportional treatment effects accounted for in the design and analysis of randomised controlled trials? A review of current practice

Background

Most clinical trials with time-to-event primary outcomes are designed assuming constant event rates and proportional hazards over time. Non-constant event rates and non-proportional hazards are seen increasingly frequently in trials. The objectives of this review were firstly to identify whether non-constant event rates and time-dependent treatment effects were allowed for in sample size calculations of trials, and secondly to assess the methods used for the analysis and reporting of time-to-event outcomes including how researchers accounted for non-proportional treatment effects.

Methods

We reviewed all original reports published between January and June 2017 in four high impact medical journals for trials for which the primary outcome involved time-to-event analysis. We recorded the methods used to analyse and present the main outcomes of the trial and assessed the reporting of assumptions underlying these methods. The sample size calculation was reviewed to see if the effect of either non-constant hazard rates or anticipated non-proportionality of the treatment effect was allowed for during the trial design.

Results

From 446 original reports we identified 66 trials with a time-to-event primary outcome encompassing trial start dates from July 1995 to November 2014. The majority of these trials (73%) had sample size calculations that used standard formulae with a minority of trials (11%) using simulation for anticipated changing event rates and/or non-proportional hazards. Well-established analytical methods, Kaplan-Meier curves (98%), the log rank test (88%) and the Cox proportional hazards model (97%), were used almost exclusively for the main outcome. Parametric regression models were considered in 11% of the reports. Of the trials reporting inference from the Cox model, only 11% reported any results of testing the assumption of proportional hazards.

Conclusions

Our review confirmed that when designing trials with time-to-event primary outcomes, methodologies assuming constant event rates and proportional hazards were predominantly used despite potential efficiencies in sample size needed or power achieved using alternative methods. The Cox proportional hazards model was used almost exclusively to present inferential results, yet testing and reporting of the pivotal assumption underpinning this estimation method was lacking.

Electronic supplementary material

The online version of this article (10.1186/s12874-019-0749-1) contains supplementary material, which is available to authorized users.

Associations between non-anaemic iron deficiency and outcomes following surgery for colorectal cancer: An exploratory study of outcomes relevant to prospective observational studies

Iron deficiency is common in colorectal cancer. Despite perioperative guidelines advocating for the correction of non-anaemic iron deficiency prior to major surgery, the impact of this pathology on postoperative outcome is unclear.

We conducted a single-centre, historical cohort study of 141 elective resections for colorectal cancer. We stratified non-anaemic patients into iron deficient and iron replete groups, and collected data on baseline characteristics, preoperative laboratory results, intraoperative events and postoperative outcomes. As this study was an exploratory work for future research, a P-value of 0.25 was considered relevant. Patients in the deficient group demonstrated lower baseline ferritin (median (interquartile range, IQR) 76 (41–141) µg/L versus 207 (140–334) µg/L, P < 0.001) and transferrin saturation (mean (standard deviation, SD) 18% (8%) versus 32% (12%), P < 0.001) than those in the replete group, and lower starting haemoglobin (mean (SD) 138 (10) g/L versus 144 (12) g/L, P = 0.01). The deficient group had increased re-admission (25% (24%) versus 4% (11%), P = 0.15) and all-cause infection (25% (24%) versus 5% (14%), P = 0.24). A decrease of two days in days alive and out of hospital at postoperative day 90 was seen in the deficient group on univariate analysis (median (IQR) 81 (75–84) versus 83 (78–84), P = 0.25). This reduced to 1.24 days in multivariate adjusted quantile regression analysis ( P = 0.22). Days alive and out of hospital at day 90, postoperative re-admission and postoperative infection may be meaningful outcome measures for future prospective observational work examining non-anaemic iron deficiency in patients undergoing major surgery for colorectal cancer.

Paraspinal muscle cross-sectional area predicts low back disability but not pain intensity

BACKGROUND AND CONTEXT

The lumbar paraspinal muscles, including the erector spinae and multifidus, play an important role in movement and control of the spine. However, our understanding of their contribution to low back pain and disability is unclear. Systematic reviews have reported conflicting evidence for an association between paraspinal muscle size and low back pain, and a paucity of data examining muscle cross-sectional area (CSA) and low back disability.

PURPOSE

To investigate the relationship between paraspinal muscle CSA and both low back pain intensity and disability.

STUDY DESIGN/SETTING

One-year longitudinal cohort study.

PATIENT SAMPLE

Participants were selected from the SpineData Registry (Denmark), which enrolls people with low back pain of 2 to 12 months duration without radiculopathy and a satisfactory response to primary intervention.

OUTCOME MEASURES

Current, typical, and worst pain in the prior 2 weeks were assessed by 11-point numeric rating scales and an average pain score was calculated, and disability was measured using the 23-item Roland-Morris Disability Questionnaire. CSA (cm²) of the lumbar paraspinal muscles was measured at levels L3-L5 from magnetic resonance images.

METHODS

Participants completed the study questionnaires and underwent the lumbar spine magnetic resonance images at baseline and were followed up 12 months later to repeat the questionnaires. Statistical analyses involved multivariable linear regression (cross-sectional analysis) and linear mixed-models (longitudinal analysis) with adjustment for confounders. Multiple imputation was conducted to account for missing data.

RESULTS

A total of 962 participants were included and 588 (65.8%) were followed up at 12-months. Multivariable analysis showed that greater paraspinal muscle CSA was associated with lower levels of disability, after adjusting for confounders (right mean CSA: baseline beta -0.16, 95% CI -0.26 to -0.06, p<.01; longitudinal beta -0.11, 95% CI -0.21 to -0.01, p=.03). This was evident at all levels, except L5 which was marginal at baseline (beta -0.08, 95% CI -0.15 to -0.001, p=.045) and not significant longitudinally (beta -0.05, 95% CI -0.12 to 0.02, p=.18). However, there were no associations between muscle CSA and pain intensity (baseline beta -0.02, 95% CI -0.06 to 0.02, p=.29; longitudinal beta -0.02, 95% CI -0.06 to 0.02, p=.34). Results were similar for both complete case and multiple imputation analyses.

CONCLUSIONS

This study found an inverse relationship between lumbar paraspinal muscle CSA and low back disability, but not pain intensity. While further investigation is needed, these findings suggest that treatment strategies directed at increasing paraspinal muscle size may be effective in reducing low back disability.

SMARThealth India: A stepped-wedge, cluster randomised controlled trial of a community health worker managed mobile health intervention for people assessed at high cardiovascular disease risk in rural India

BACKGROUND

Cardiovascular diseases (CVD) are rising in India resulting in major health system challenges.

METHODS

Eighteen primary health centre (PHC) clusters in rural Andhra Pradesh were randomised over three, 6-month steps to an intervention comprising: (1) household CVD risk assessments by village-based community health workers (CHWs) using a mobile tablet device; (2) electronic referral and clinical decision support for PHC doctors; and (3) a tracking system for follow-up care. Independent data collectors screened people aged ≥ 40 years in 54 villages serviced by the PHCs to create a high CVD risk cohort (based on WHO risk charts and blood pressure thresholds). Randomly selected, independent samples, comprising 15% of this cohort, were reviewed at each 6-month step. The primary outcome was the proportion meeting systolic blood pressure (SBP) targets (<140mmHg).

FINDINGS

Eight-four percent of the eligible population (n = 62,254) were assessed at baseline (18.4% at high CVD risk). Of those at high risk, 75.3% were followed up over two years. CHWs screened 85.9% of the baseline cohort and doctors followed up 70.0% of all high risk referrals. There was no difference in the proportion of people achieving SBP targets (41.2% vs 39.2%; adjusted odds ratio (OR) 1.01 95% CI 0.76-1.35) or receiving BP-lowering medications in the intervention vs control periods respectively. There was a high discordance in risk scores generated by independent data collectors and CHWs, resulting in only 37.2% of the evaluation cohort exposed to the intervention. This discordance was mainly driven by fluctuating BP values (both normal variability and marked seasonal variations). In the pre-specified high risk concordant subgroup, there was greater use of BP-lowering medications in the intervention period (54.3% vs 47.9%, OR 1.22, 95% CI 1.03-1.44) but no impact on BP control.

CONCLUSIONS

The strategy was well implemented with increased treatment rates among high risk individuals assessed by CHWs, however effects on BP were not demonstrated. Use of guideline-recommended BP thresholds for identifying high risk individuals substantially affected the reproducibility of risk assessment, and thus the ability to reliably evaluate the effectiveness of the intervention. In addition, unanticipated seasonal variation in BP in the context of a stepped-wedge trial highlights the inherent risks of this study design.

TRIAL REGISTRATION

Clinical Trials Registry of India CTRI/2013/06/ 003753.

Accounting for a decaying correlation structure in cluster randomized trials with continuous recruitment

A requirement for calculating sample sizes for cluster randomized trials (CRTs) conducted over multiple periods of time is the specification of a form for the correlation between outcomes of subjects within the same cluster, encoded via the within-cluster correlation structure. Previously proposed within-cluster correlation structures have made strong assumptions; for example, the usual assumption is that correlations between the outcomes of all pairs of subjects are identical ("uniform correlation"). More recently, structures that allow for a decay in correlation between pairs of outcomes measured in different periods have been suggested. However, these structures are overly simple in settings with continuous recruitment and measurement. We propose a more realistic "continuous-time correlation decay" structure whereby correlations between subjects' outcomes decay as the time between these subjects' measurement times increases. We investigate the use of this structure on trial planning in the context of a primary care diabetes trial, where there is evidence of decaying correlation between pairs of patients' outcomes over time. In particular, for a range of different trial designs, we derive the variance of the treatment effect estimator under continuous-time correlation decay and compare this to the variance obtained under uniform correlation. For stepped wedge and cluster randomized crossover designs, incorrectly assuming uniform correlation will underestimate the required sample size under most trial configurations likely to occur in practice. Planning of CRTs requires consideration of the most appropriate within-cluster correlation structure to obtain a suitable sample size.

Cardiovascular disease risk and comparison of different strategies for blood pressure management in rural India

BACKGROUND

Non-optimal blood pressure (BP) levels are a major cause of disease burden globally. We describe current BP and treatment patterns in rural India and compare different approaches to BP lowering in this setting.

METHODS

All individuals aged ≥40 years from 54 villages in a South Indian district were invited and 62,194 individuals (84%) participated in a cross-sectional study. Individual 10-year absolute cardiovascular disease (CVD) risk was estimated using WHO/ISH charts. Using known effects of treatment, proportions of events that would be averted under different paradigms of BP lowering therapy were estimated.

RESULTS

After imputation of pre-treatment BP levels for participants on existing treatment, 76·9% (95% confidence interval, 75.7-78.0%), 5·3% (4.9-5.6%), and 17·8% (16.9-18.8%) of individuals had a 10-year CVD risk defined as low (< 20%), intermediate (20-29%), and high (≥30%, established CVD, or BP > 160/100 mmHg), respectively. Compared to the 19.6% (18.4-20.9%) of adults treated with current practice, a slightly higher or similar proportion would be treated using an intermediate (23·2% (22.0-24.3%)) or high (17·9% (16.9-18.8%) risk threshold for instituting BP lowering therapy and this would avert 87·2% (85.8-88.5%) and 62·7% (60.7-64.6%) more CVD events over ten years, respectively. These strategies were highly cost-effective relative to the current practice.

CONCLUSION

In a rural Indian community, a substantial proportion of the population has elevated CVD risk. The more efficient and cost-effective clinical approach to BP lowering is to base treatment decisions on an estimate of an individual's short-term absolute CVD risk rather than with BP based strategy.

CLINICAL TRIAL REGISTRATION

Clinical Trials Registry of India CTRI/2013/06/003753 , 14 June 2013.

Efficacy of Low-Dose Amitriptyline for Chronic Low Back Pain: A Randomized Clinical Trial

IMPORTANCE

Antidepressants at low dose are commonly prescribed for the management of chronic low back pain and their use is recommended in international clinical guidelines. However, there is no evidence for their efficacy.

OBJECTIVE

To examine the efficacy of a low-dose antidepressant compared with an active comparator in reducing pain, disability, and work absence and hindrance in individuals with chronic low back pain.

DESIGN, SETTING, AND PARTICIPANTS

A double-blind, randomized clinical trial with a 6-month follow-up of adults with chronic, nonspecific, low back pain who were recruited through hospital/medical clinics and advertising was carried out.

INTERVENTION

Low-dose amitriptyline (25 mg/d) or an active comparator (benztropine mesylate, 1 mg/d) for 6 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was pain intensity measured at 3 and 6 months using the visual analog scale and Descriptor Differential Scale. Secondary outcomes included disability assessed using the Roland Morris Disability Questionnaire and work absence and hindrance assessed using the Short Form Health and Labour Questionnaire.

RESULTS

Of the 146 randomized participants (90 [61.6%] male; mean [SD] age, 54.8 [13.7] years), 118 (81%) completed 6-month follow-up. Treatment with low-dose amitriptyline did not result in greater pain reduction than the comparator at 6 (adjusted difference, -7.81; 95% CI, -15.7 to 0.10) or 3 months (adjusted difference, -1.05; 95% CI, -7.87 to 5.78), independent of baseline pain. There was no statistically significant difference in disability between the groups at 6 months (adjusted difference, -0.98; 95% CI, -2.42 to 0.46); however, there was a statistically significant improvement in disability for the low-dose amitriptyline group at 3 months (adjusted difference, -1.62; 95% CI, -2.88 to -0.36). There were no differences between the groups in work outcomes at 6 months (adjusted difference, absence: 1.51; 95% CI, 0.43-5.38; hindrance: 0.53; 95% CI, 0.19-1.51), or 3 months (adjusted difference, absence: 0.86; 95% CI, 0.32-2.31; hindrance: 0.78; 95% CI, 0.29-2.08), or in the number of participants who withdrew owing to adverse events (9 [12%] in each group; χ2 = 0.004; P = .95).

CONCLUSIONS AND RELEVANCE

This trial suggests that amitriptyline may be an effective treatment for chronic low back pain. There were no significant improvements in outcomes at 6 months, but there was a reduction in disability at 3 months, an improvement in pain intensity that was nonsignificant at 6 months, and minimal adverse events reported with a low-dose, modest sample size and active comparator. Although large-scale clinical trials that include dose escalation are needed, it may be worth considering low-dose amitriptyline if the only alternative is an opioid.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12612000131853.

Dexamethasone for Cardiac Surgery trial (DECS-II): Rationale and a novel, practice preference-randomized consent design

BACKGROUND

Numerous studies have investigated high-dose corticosteroids in cardiac surgery, but with mixed results leading to ongoing variations in practice around the world. DECS-II is a study comparing high-dose dexamethasone with placebo in patients undergoing cardiac surgery.

METHODS

We discuss the rationale for conducting DECS-II, a 2800-patient, pragmatic, multicenter, assessor-blinded, randomized trial in cardiac surgery, and the features of the DECS-II study design (objectives, end points, target population, based on practice preference with post-randomization consent, treatments, patient follow-up and analysis).

CONCLUSIONS

The DECS-II trial will use a novel, efficient trial design to evaluate whether high-dose dexamethasone has a patient-centered benefit of enhancing recovery and increasing the number of days at home after cardiac surgery.

Comparing two methods for delivering clinical trial informed consent information to older adults: singular versus stepped approach

BACKGROUND

Adapting the informed consent process to the needs of older adults may enhance engagement and willingness to participate in a clinical trial. A key aspect of the process is being provided with written clinical trial information and consent documents and having an opportunity to discuss the information with the researcher. However, there are no guidelines on the most appropriate method for delivering this information to older adults and it is not known whether the delivery method is a facilitator or barrier towards clinical trial participation.

AIMS

To compare two delivery methods of informed consent on recruitment, refusal to continue and randomisation rates in a general practice-based clinical trial involving older adults.

METHODS

In a matched cohort sub-study as part of the STAtins in Reducing Events in the Elderly clinical trial, 520 participants were allocated into two groups by age, gender and attending general practice location, to receive the trial information and consent form in the mail (Method 1) prior to the first baseline visit or in person (Method 2) at the visit where a comprehensive informed consent process took place.

RESULTS

Compared with Method 1, potential participants assigned to Method 2 were more likely to agree to attend the first baseline screening visit (refusal rate 20% vs 13.5%, respectively, p = 0.05). However, there was no significant difference in the proportion of participants recruited into the trial by providing written informed consent at the first baseline screening visit. For each informed consent delivery method, similar proportions of participants refused to take part in the trial by the end of the screening phase. Randomisation rates in the two groups were also similar. Time to conduct the informed consent procedure took significantly longer with Method 2 compared with Method 1 (median time 20 vs 15 min, respectively, p < 0.01). Interest in the research trial topic was the main reason cited (33.4%) for considering trial participation.

CONCLUSION

Later delivery of informed consent documents to potential participants in this trial was associated with a small increase in attendance at the first, in person, screening visit. However, the randomisation rate of participants into the trial was not affected by the method and timing of delivery of informed consent information. Similar randomisation rates occurred whether potential participants were mailed informed consent documents prior to the first in person screening visit or were given the information at the screening visit.