Assessing the impact of risk-based data monitoring on outcomes for a paediatric multicentre randomised controlled trial

BACKGROUND/AIMS

Regulatory guidelines recommend that sponsors develop a risk-based approach to monitoring clinical trials. However, there is a lack of evidence to guide the effective implementation of monitoring activities encompassed in this approach. The aim of this study was to assess the efficiency and impact of the risk-based monitoring approach used for a multicentre randomised controlled trial comparing treatments in paediatric patients undergoing cardiac bypass surgery.

METHODS

This is a secondary analysis of data from a randomised controlled trial that implemented targeted source data verification as part of the risk-based monitoring approach. Monitoring duration and source to database error rates were calculated across the monitored trial dataset. The monitored and unmonitored trial dataset, and simulated trial datasets with differing degrees of source data verification and cohort sizes were compared for their effect on trial outcomes.

RESULTS

In total, 106,749 critical data points across 1,282 participants were verified from source data either remotely or on-site during the trial. The total time spent monitoring was 365 hours, with a median (interquartile range) of 10 (7, 16) minutes per participant. An overall source to database error rate of 3.1% was found, and this did not differ between treatment groups. A low rate of error was found for all outcomes undergoing 100% source data verification, with the exception of two secondary outcomes with error rates >10%. Minimal variation in trial outcomes were found between the unmonitored and monitored datasets. Reduced degrees of source data verification and reduced cohort sizes assessed using simulated trial datasets had minimal impact on trial outcomes.

CONCLUSIONS

Targeted source data verification of data critical to trial outcomes, which carried with it a substantial time investment, did not have an impact on study outcomes in this trial. This evaluation of the cost-effectiveness of targeted source data verification contributes to the evidence-base regarding the context where reduced emphasis should be placed on source data verification as the foremost monitoring activity.

Longitudinal cohort study investigating neurodevelopmental and socioemotional outcomes in school-entry aged children after open heart surgery in Australia and New Zealand: the NITRIC follow-up study protocol

INTRODUCTION

Despite growing awareness of neurodevelopmental impairments in children with congenital heart disease (CHD), there is a lack of large, longitudinal, population-based cohorts. Little is known about the contemporary neurodevelopmental profile and the emergence of specific impairments in children with CHD entering school. The performance of standardised screening tools to predict neurodevelopmental outcomes at school age in this high-risk population remains poorly understood. The NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC) trial randomised 1371 children <2 years of age, investigating the effect of gaseous nitric oxide applied into the cardiopulmonary bypass oxygenator during heart surgery. The NITRIC follow-up study will follow this cohort annually until 5 years of age to assess outcomes related to cognition and socioemotional behaviour at school entry, identify risk factors for adverse outcomes and evaluate the performance of screening tools.

METHODS AND ANALYSIS

Approximately 1150 children from the NITRIC trial across five sites in Australia and New Zealand will be eligible. Follow-up assessments will occur in two stages: (1) annual online screening of global neurodevelopment, socioemotional and executive functioning, health-related quality of life and parenting stress at ages 2-5 years; and (2) face-to-face assessment at age 5 years assessing intellectual ability, attention, memory and processing speed; fine motor skills; language and communication; and socioemotional outcomes. Cognitive and socioemotional outcomes and trajectories of neurodevelopment will be described and demographic, clinical, genetic and environmental predictors of these outcomes will be explored.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Children's Health Queensland (HREC/20/QCHQ/70626) and New Zealand Health and Disability (21/NTA/83) Research Ethics Committees. The findings will inform the development of clinical decision tools and improve preventative and intervention strategies in children with CHD. Dissemination of the outcomes of the study is expected via publications in peer-reviewed journals, presentation at conferences, via social media, podcast presentations and medical education resources, and through CHD family partners.

TRIAL REGISTRATION NUMBER

The trial was prospectively registered with the Australian New Zealand Clinical Trials Registry as 'Gene Expression to Predict Long-Term Neurodevelopmental Outcome in Infants from the NITric oxide during cardiopulmonary bypass to improve Recovery in Infants with Congenital heart defects (NITRIC) Study - A Multicentre Prospective Trial'.

TRIAL REGISTRATION

ACTRN12621000904875.

Mean-field crack networks on desiccated films and their applications: Girl with a Pearl Earring

Usual requirements for bulk and fissure energies are considered in obtaining the interdependence among external stress, thickness and area of crack polygons in desiccated films. The average area of crack polygons increases with thickness as a power-law of 4/3. The sequential fragmentation process is characterized by a topological factor related to a scaling finite procedure. Non-sequential overly tensioned (prompt) fragmentation is briefly discussed. Vermeer's painting, Girl with a Pearl Earring, is considered explicitly by using computational image tools and simple experiments and applying the proposed theoretical analysis. In particular, concerning the source of lightened effects on the girl's face, the left/right thickness layer ratio (≈1.34) and the stress ratio (≈1.102) are evaluated. Other master paintings are briefly considered.

Competitive Exclusion and Axiomatic Set-Theory: De Morgan's Laws, Ecological Virtual Processes, Symmetries and Frozen Diversity

This work applies the competitive exclusion principle and the concept of potential competitors as simple axiomatic tools to generalized situations in ecology. These tools enable apparent competition and its dual counterpart to be explicitly evaluated in poorly understood ecological systems. Within this set-theory framework we explore theoretical symmetries and invariances, De Morgan's laws, frozen evolutionary diversity and virtual processes. In particular, we find that the exclusion principle compromises the geometrical growth of the number of species. By theoretical extending this principle, we can describe interspecific depredation in the dual case. This study also briefly considers the debated situation of intraspecific competition. The ecological consequences of our findings are discussed; particularly, the use of our framework to reinterpret coupled mathematical differential equations describing certain ecological processes.

Intermittence for humans spreading 45,000 years ago: from Eurasia to the Americas

From northeastern Eurasia to the Americas, a three-stage spread of modern humans is considered through large-scale intermittence (exploitation/relocation). Conceptually, this work supports intermittence as a real strategy for colonization of new habitats. For the first stage, northeastern Eurasia travel, we adapt our model to archaeological dates determining the diffusion coefficient (exploitation phase) as D = 299.44 km2/yr and the velocity parameter (relocation phase) as vo = 4.8944 km/yr. The relative phase weight (✧0.46) between both kinds of motions is consistent with a moderate biological population rate (r΄ ✧ 0.0046/yr). The second stage is related to population fragmentation. The last stage, reaching Alaska, corresponds essentially to relocation (vo ✧ 0.75 km/yr).

Stability in air of silver and silver oxide nanoparticle shells deposited over silica spheres without using coupling agents

The deposition of silver nanoparticles on the surface of silica was carried out using our simple, robust and rapid chemical method without surface modification of silica or added coupling agents. The process was carried out at room temperature using water/methanol mixtures, tetraethyl orthosilicate as Si source and silver nanoparticles (NPs) in a single-pot reaction. Using EDS, XRD, HRTEM and High Angle Annular Dark Field (HAADF) STEM characterization techniques, we have found the coexistence of silver NPs and silver oxides NPs anchored to the surface of sub-micron silica spheres, with Ag NPs predominating sizes around 2-3 nm approximately, and Ag2O NPs sizes over 10 nm.

A mathematical model for the Andean Tiwanaku civilization collapse: climate variations

We propose a mathematical nonlinear model for the Tiwanaku civilization collapse based on the assumption, supported by archeological data, that a drought caused a lack of the main resource, water. We evaluate the parameter of our model using archaeological data. According to our numerical simulation the population core should have decreased from 45,000 to 2000 inhabitants due to lake surface contraction.

Late renal vein thrombosis associated with recurrence of membranous nephropathy in a renal allograft: a case report

Allograft renal vein thrombosis (RVT) is an uncommon but potentially catastrophic complication. Although it usually occurs in the early posttransplant period and is associated with surgical complications or vascular rejection, it may develop later, when it is generally related with a hypercoagulable state. Typical clinical presentation is sudden oligoanuric acute renal failure, and hematuria, with a painful and swollen renal allograft. Confirmation of the diagnosis requires Doppler ultrasound and computed tomography. Herein we have reported a successfully treated case of late RVT that developed in an allograft with recurrent membranous nephropathy associated with the nephrotic syndrome. The patient fully recovered renal graft function a few days after presentation, which was related to anticoagulant therapy. We demonstrated complete recanalization of the venous thrombosis.

A mathematical model for Neanderthal extinction

A simple mathematical homogeneous model of competition is used to describe Neanderthal extinction in Europe. It considers two interacting species, Neanderthals and Early Modern Men, in the same ecological niche. Using paleontological data we claim that the parameter of similarity, between both species, fluctuates between 0.992 and 0.997. An extension of the model including migration (diffusion) is also discussed; nevertheless, extinction of Neanderthal seems unavoidable. Numerical analysis of travelling wave solutions (fronts) confirms the extinction. The wave-front-velocity is estimated from linear analysis and numerical simulations confirm this estimation. We conjecture a mathematical formulation for the principle of exclusion between competitive interacting species (Gause).

[Non-syndromic familial deafness. Review and genetic study]

Many cases of hearing impairment are of genetic origin. Non-syndromic recessive transmission is the most frequent form. A genetic study was made of cases of non-syndromic familial hearing impairment seen in our service. The pattern of Mendelian inheritance was studied in the disorders associated with deafness. Four families had non-syndromic deafness and autosomal inheritance (3 dominant and one recessive) and one had a probable sex-linked inheritance. Genetic counseling was given and guidelines were created after reviewing the literature.

[IgA nephropathy (Berger's disease). Our experience in 78 cases]

We studied 78 patients with a diagnosis of IgA nephropathy. Renal biopsy was indicated in 69 patients by the presence of macroscopic hematuria (52%), microhematuria or proteinuria (22%), nephrotic syndrome (10%), severe hypertension with microhematuria or renal failure (14%) or nephritic syndrome (1%). Nine were healthy subjects being studied as live kidney donors. An association with IgG and/or IgM was present in 92% of patients. Serum IgA was elevated in 36% of patients. Hypertension was present in 30% and decreased renal function in 29%. Patients with serum creatinine above 1.5 mg/dl tended to be older (33.8 vs 28.7 years) and to have hypertension (52% vs 19%). Among 25 patients followed for more than 12 months renal function remained stable in 44%, deteriorated in 20% and 36% developed renal failure. The latter was associated to older age, hypertension, absence of macroscopic hematuria and nephrotic syndrome. The 9 live donors had no clinical manifestations of renal disease. Thus, IgA nephropathy is a highly variable clinical entity, both in its manifestations and its prognosis. An asymptomatic course is demonstrated in some subjects.

[Lupus nephropathy: difficulties in its treatment]

The management of the patient with lupus nephropathy is still difficult. A new classification considering activity and chronicity indexes has revalued the histologic assessment as a prognostic and therapeutic guide. The benefits of immunosuppressive drugs in preventing progression of renal disease have been clarified and adverse effects reduced by new methods of administration. A key aspect of therapy is still individual selection of type and intensity of immunosuppression, that must be adjusted to the changing nature of the disease. Therapy must be balanced between optimal levels of efficacy and minimal toxicity.

DNA binding factors for the CpG-rich island containing the promoter of the human X-linked PGK gene

The gene coding for the glycolytic enzyme phosphoglycerate kinase (PGK-1) is X-linked in mammals and has a G+C-rich 5' region characteristic of several constitutive genes. Despite the fact that PGK-1 is constitutively expressed, it is transcriptionally regulated in female cells by X chromosome inactivation. To study the expression and regulation of the PGK-1 gene, we have analyzed the binding of trans-acting factors to the 5' region of the PGK-1 gene. We detect at least three distinct binding activities that interact in a sequence-specific manner in vitro with at least six different sites in the 5' region. Two of these binding activities generate DNase I-protected footprints centered approximately 360 bp and 130 bp upstream of the transcription start point. We have examined the promoter specificity of the three binding activities in gel mobility-shift assays by competition with cloned promoter fragments of other genes. None of the binding activities interacts exclusively with X-linked promoters. However, one activity binds preferentially to G+C-rich promoters, and another activity appears to bind preferentially to only two of the promoters tested. Previous studies have demonstrated that one HpaII/MspI site, which is included within a footprinted region observed in this study, is fully methylated in the inactive X chromosome and totally unmethylated on the active X chromosome. Competition studies using synthetic oligonucleotides containing 5-methylcytosine at all CpG sites in this region demonstrate that DNA methylation does not significantly alter the affinity between the corresponding binding activity and this binding site.

Response of Drosophila embryonic cells to tumor promoters

Several recent observations on tumor promoters point to the many developmental and embryonic characteristics associated with their mode of action. These observations have led us to investigate the effects of a series of tumor promoters on Drosophila embryonic cultures at both the morphological and molecular levels. The cultures have been used with some success by us to assess the teratogenic potential of a large number of molecules, including drugs, chemicals, and environmental pollutants. In this culture system, 12-O-tetradecanoylphorbol 13-acetate (TPA), the most potent of the tumor promoters tested, disrupted normal muscle and neuron differentiation at concentrations ranging from 0.1 to 10 microM; 4-O-methylphorbol 12-myristate a weak stage I promoter, used at concentrations the same as or higher than those of TPA had no inhibitory effect on cell differentiation. A selected group of tumor promoters was also investigated at the molecular level for their effects on differentiating Drosophila cells. All tumor promoters tested induced synthesis of three heat shock proteins. On the basis of these two levels of effects (morphological and molecular) it is apparent that the tumor promoters tested act similarly as teratogens do in the Drosophila embryonic cultures. This finding confirms some recent published reports suggesting that a large number of tumor promoters act as teratogens if the exposure interval is during the embryonic rather than the adult stage. We suggest that this system can be usefully employed to investigate some of the common mechanisms involved in tumor promotion and teratogenesis.

Clinical and immunological evolution of oligoanuric anti-GBM nephritis treated by haemodialysis

Eight patients with oligoanuric anti-glomerular-basement-membrane (GBM), antibody-mediated glomerulonephritis without lung haemorrhage who were not treated with plasma exchange therapy were reviewed. All had severe crescentic nephritis and required dialysis. Circulating anti-GBM antibodies disappeared gradually and spontaneously in all patients. The autoantibodies became undetectable in five patients after an average of 11 months. No patient recovered renal function. Two patients have been successfully transplanted and anti-GBM nephritis has not recurred. One of these needed a pre-transplant course of plasma exchange and immunosuppression to reduce a slightly raised anti-GBM antibody titre. Of five patients who remain on dialysis, only two cannot be transplanted due to the persistence of circulating autoantibodies. One patient died from causes unrelated to renal disease. Oligoanuric patients with anti-GBM nephritis who need dialysis rarely benefit from aggressive therapy unless lung haemorrhage is present.