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1.
BMC Med Res Methodol ; 23(1): 25, 2023 01 25.
Article in English | MEDLINE | ID: covidwho-2214531

ABSTRACT

BACKGROUND: Numerous clinical trials have been initiated to find effective treatments for COVID-19. These trials have often been initiated in regions where the pandemic has already peaked. Consequently, achieving full enrollment in a single trial might require additional COVID-19 surges in the same location over several years. This has inspired us to pool individual patient data (IPD) from ongoing, paused, prematurely-terminated, or completed randomized controlled trials (RCTs) in real-time, to find an effective treatment as quickly as possible in light of the pandemic crisis. However, pooling across trials introduces enormous uncertainties in study design (e.g., the number of RCTs and sample sizes might be unknown in advance). We sought to develop a versatile treatment efficacy assessment model that accounts for these uncertainties while allowing for continuous monitoring throughout the study using Bayesian monitoring techniques. METHODS: We provide a detailed look at the challenges and solutions for model development, describing the process that used extensive simulations to enable us to finalize the analysis plan. This includes establishing prior distribution assumptions, assessing and improving model convergence under different study composition scenarios, and assessing whether we can extend the model to accommodate multi-site RCTs and evaluate heterogeneous treatment effects. In addition, we recognized that we would need to assess our model for goodness-of-fit, so we explored an approach that used posterior predictive checking. Lastly, given the urgency of the research in the context of evolving pandemic, we were committed to frequent monitoring of the data to assess efficacy, and we set Bayesian monitoring rules calibrated for type 1 error rate and power. RESULTS: The primary outcome is an 11-point ordinal scale. We present the operating characteristics of the proposed cumulative proportional odds model for estimating treatment effectiveness. The model can estimate the treatment's effect under enormous uncertainties in study design. We investigate to what degree the proportional odds assumption has to be violated to render the model inaccurate. We demonstrate the flexibility of a Bayesian monitoring approach by performing frequent interim analyses without increasing the probability of erroneous conclusions. CONCLUSION: This paper describes a translatable framework using simulation to support the design of prospective IPD meta-analyses.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , Computer Simulation , Research Design , Sample Size , Bayes Theorem
2.
Respirology ; 27(10): 834-843, 2022 10.
Article in English | MEDLINE | ID: covidwho-1973716

ABSTRACT

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.


Subject(s)
COVID-19 , Pulmonary Medicine , Bayes Theorem , Clinical Trials as Topic , Humans , Oxygen , Pandemics , Research Design
3.
2022 International Mobile and Embedded Technology Conference, MECON 2022 ; : 297-301, 2022.
Article in English | Scopus | ID: covidwho-1840282

ABSTRACT

The burial of bodies became a trend in the cause of ongoing pending (Novel Coronavirus), more than50 a million people all over the globe are adversely affected, hence the analysis and forecasting techniques are necessary to regain the human livelihood. The enlargement of technologies such as Artificial Intelligence, Machine Learning, Deep Learning, are en route into all the living aspects. Hence by using AI, ML, DL, Advanced technologies and existing models ARIMA, PROPHET, SVM, RNN, Faster Mask R-CNN, RESNET-50, and other techniques such as logarithmic scaling and exponential smoothing so on, the spread of VIRUS, the effect of countries economic growth, confirmed cases, fatality rate, recoveries are predicted to overcome the life threat due to SARS. Such that different predictive techniques are used to forecast. The advancement in the past algorithms to acquire accurate results are been introduced and described. © 2022 IEEE.

4.
Trials ; 22(1): 573, 2021 Aug 28.
Article in English | MEDLINE | ID: covidwho-1817236

ABSTRACT

BACKGROUND: SARS-CoV-2 binds to membrane-bound angiotensin-converting enzyme 2 (ACE2) which may result in downregulation of membrane-bound ACE2. ACE2 is a key regulator of the renin-angiotensin system (RAS) and is responsible for degrading angiotensin II and thereby counteracting its pro-inflammatory, pro-fibrotic effects mediated through the angiotensin II type 1 receptor (AT1R). As AT1R is directly blocked by angiotensin receptor blockers (ARBs), these agents may offer a safe, low-cost solution for reducing COVID-19 respiratory outcomes. METHODS AND DISCUSSION: CLARITY is a pragmatic, adaptive, two-arm, multi-centre, comparative effectiveness phase III randomised controlled trial that examines whether ARBs reduce COVID-19 severity among high-risk patients. Recruiting in India and Australia, the trial will compare treatment with a maximum tolerated daily dose of an ARB to standard of care. Treatment allocation is blinded in India but open-label in Australia due to interruptions to placebo supply in the latter. The primary endpoint is a 7-point ordinal scale of clinical states, ranging from no limitation of activities (category 1) to death (category 7), assessed on day 14. Secondary outcomes include the 7-point scale assessed at day 28 and 28- and 90-day mortality. The design adapts the sample size based on accumulating data via frequent interim analyses and the use of predictive probability to determine whether the current sample size is sufficient or continuing accrual would be futile. The trial commenced recruitment on 18 August 2020. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04394117 . Registered on 19 May 2020. Clinical Trial Registry of India: CTRI/2020/07/026831).


Subject(s)
Angiotensin Receptor Antagonists , COVID-19 , Angiotensin-Converting Enzyme Inhibitors/adverse effects , Humans , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Renin-Angiotensin System , SARS-CoV-2
5.
International Journal of Agricultural and Statistical Sciences ; 17:2169-2173, 2021.
Article in English | Scopus | ID: covidwho-1733012

ABSTRACT

Restricted data plays a significant role in describing economic, social, medical, with other phenomena. Most of the time the Restricted point on zero, so the appropriate regression model for this type of data is a Tobit regression model. When the number of independent variables is too large, the process of their interpretation is very complex. To get around this problem, it is possible to use Variable Selections. In the current paper, we will use the adaptive Lasso through the Bayesian method. Also, the Bayesians Lasso method has many advantages that provide accuracy in the results, especially in the selection of Variable Selections. To compare our proposal, we will use the number of infections with Covid-19 for a group of families through a field survey in Al-Qadisiyah Governorate and identify the effective factors. © 2021 DAV College. All rights reserved.

6.
Ann Am Thorac Soc ; 17(7): 879-891, 2020 07.
Article in English | MEDLINE | ID: covidwho-679536

ABSTRACT

There is broad interest in improved methods to generate robust evidence regarding best practice, especially in settings where patient conditions are heterogenous and require multiple concomitant therapies. Here, we present the rationale and design of a large, international trial that combines features of adaptive platform trials with pragmatic point-of-care trials to determine best treatment strategies for patients admitted to an intensive care unit with severe community-acquired pneumonia. The trial uses a novel design, entitled "a randomized embedded multifactorial adaptive platform." The design has five key features: 1) randomization, allowing robust causal inference; 2) embedding of study procedures into routine care processes, facilitating enrollment, trial efficiency, and generalizability; 3) a multifactorial statistical model comparing multiple interventions across multiple patient subgroups; 4) response-adaptive randomization with preferential assignment to those interventions that appear most favorable; and 5) a platform structured to permit continuous, potentially perpetual enrollment beyond the evaluation of the initial treatments. The trial randomizes patients to multiple interventions within four treatment domains: antibiotics, antiviral therapy for influenza, host immunomodulation with extended macrolide therapy, and alternative corticosteroid regimens, representing 240 treatment regimens. The trial generates estimates of superiority, inferiority, and equivalence between regimens on the primary outcome of 90-day mortality, stratified by presence or absence of concomitant shock and proven or suspected influenza infection. The trial will also compare ventilatory and oxygenation strategies, and has capacity to address additional questions rapidly during pandemic respiratory infections. As of January 2020, REMAP-CAP (Randomized Embedded Multifactorial Adaptive Platform for Community-acquired Pneumonia) was approved and enrolling patients in 52 intensive care units in 13 countries on 3 continents. In February, it transitioned into pandemic mode with several design adaptations for coronavirus disease 2019. Lessons learned from the design and conduct of this trial should aid in dissemination of similar platform initiatives in other disease areas.Clinical trial registered with www.clinicaltrials.gov (NCT02735707).


Subject(s)
Community-Acquired Infections/therapy , Coronavirus Infections/therapy , Influenza, Human/therapy , Pneumonia, Viral/therapy , Pneumonia/therapy , Anti-Bacterial Agents/therapeutic use , Antiviral Agents/therapeutic use , Betacoronavirus , COVID-19 , Evidence-Based Medicine , Humans , Pandemics , Point-of-Care Systems , SARS-CoV-2
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