Conditional copula models for correlated survival endpoints: Individual patient data meta-analysis of randomized controlled trials

2021 ◽  
pp. 096228022110463
Author(s):  
Takeshi Emura ◽  
Casimir Ledoux Sofeu ◽  
Virginie Rondeau
Keyword(s):  
Randomized Controlled Trials ◽  
Individual Patient Data ◽  
Controlled Trials ◽  
Kendall’S Tau ◽  
Kendall's Tau ◽  
Randomized Controlled ◽  
Conditional Copula ◽  
Survival Endpoints ◽  
Definition Of ◽  
Meta Analyses

Correlations among survival endpoints are important for exploring surrogate endpoints of the true endpoint. With a valid surrogate endpoint tightly correlated with the true endpoint, the efficacy of a new drug/treatment can be measurable on it. However, the existing methods for measuring correlation between two endpoints impose an invalid assumption: correlation structure is constant across different treatment arms. In this article, we reconsider the definition of Kendall's concordance measure (tau) in the context of individual patient data meta-analyses of randomized controlled trials. According to our new definition of Kendall's tau, its value depends on the treatment arms. We then suggest extending the existing copula (and frailty) models so that their Kendall's tau can vary across treatment arms. Our newly proposed model, a joint frailty-conditional copula model, is the implementation of the new definition of Kendall's tau in meta-analyses. In order to facilitate our approach, we develop an original R function condCox.reg(.) and make it available in the R package joint.Cox ( https://CRAN.R-project.org/package=joint.Cox ). We apply the proposed method to a gastric cancer dataset (3288 patients in 14 randomized trials from the GASTRIC group). This data analysis concludes that Kendall's tau has different values between the surgical treatment arm and the adjuvant chemotherapy arm ( p-value<0.001), whereas disease-free survival remains a valid surrogate at individual level for overall survival in these trials.

Otorhinolaryngology

2016 ◽  
Keyword(s):  
Primary Care ◽  
Randomized Controlled Trials ◽  
General Practitioners ◽  
Individual Patient Data ◽  
Controlled Trials ◽  
Evidence Based ◽  
Randomized Controlled ◽  
The Past ◽  
Meta Analyses ◽  
Based Medicine

Conditions of the ear, nose, or throat (ENT) are common diagnoses in primary care and are a frequent indication for referral to secondary care. They have a major impact on health and health-care resources, and it is therefore important that the management of ENT conditions is based upon the best available evidence. Such evidence should come from methodologically sound research in patients representative of those seen in everyday practice. Over the past decades, general practitioners and ENT surgeons have embraced the principles of evidence-based medicine, actively contributing to randomized controlled trials in this field. Consequently, management of ENT conditions is shifting from experience-based to evidence-based. The randomized controlled trials and individual patient data meta-analyses presented in this chapter have been instrumental in the development of clinical guidelines that allow general practitioners and ENT surgeons to make evidence-based shared decisions for the management of some of the commonest ENT conditions.

scholarly journals Pre-Procedural Lumbar Neuraxial Ultrasound—A Systematic Review of Randomized Controlled Trials and Meta-Analysis

Healthcare ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 479
Author(s):  
Tatiana Sidiropoulou ◽  
Kalliopi Christodoulaki ◽  
Charalampos Siristatidis
Keyword(s):  
Systematic Review ◽  
Lumbar Spine ◽  
Randomized Controlled Trials ◽  
Success Rate ◽  
Meta Analysis ◽  
Controlled Trials ◽  
Technical Failure ◽  
Obese Patients ◽  
Randomized Controlled ◽  
Meta Analyses

A pre-procedural ultrasound of the lumbar spine is frequently used to facilitate neuraxial procedures. The aim of this review is to examine the evidence sustaining the utilization of pre-procedural neuraxial ultrasound compared to conventional methods. We perform a systematic review of randomized controlled trials with meta-analyses. We search the electronic databases Medline, Cochrane Central, Science Direct and Scopus up to 1 June 2019. We include trials comparing a pre-procedural lumbar spine ultrasound to a non-ultrasound-assisted method. The primary endpoints are technical failure rate, first-attempt success rate, number of needle redirections and procedure time. We retrieve 32 trials (3439 patients) comparing pre-procedural lumbar ultrasounds to palpations for neuraxial procedures in various clinical settings. Pre-procedural ultrasounds decrease the overall risk of technical failure (Risk Ratio (RR) 0.69 (99% CI, 0.43 to 1.10), p = 0.04) but not in obese and difficult spinal patients (RR 0.53, p = 0.06) and increase the first-attempt success rate (RR 1.5 (99% CI, 1.22 to 1.86), p < 0.0001, NNT = 5). In difficult spines and obese patients, the RR is 1.84 (99% CI, 1.44 to 2.3; p < 0.0001, NNT = 3). The number of needle redirections is lower with pre-procedural ultrasounds (SMD = −0.55 (99% CI, −0.81 to −0.29), p < 0.0001), as is the case in difficult spines and obese patients (SMD = −0.85 (99% CI, −1.08 to −0.61), p < 0.0001). No differences are observed in procedural times. Ιn conclusion, a pre-procedural ultrasound provides significant benefit in terms of technical failure, number of needle redirections and first attempt-success rate. Τhe effect of pre-procedural ultrasound scanning of the lumbar spine is more significant in a subgroup analysis of difficult spines and obese patients.

scholarly journals Effects of early extubation followed by noninvasive ventilation versus standard extubation on the duration of invasive mechanical ventilation in hypoxemic non-hypercapnic patients: a systematic review and individual patient data meta-analysis of randomized controlled trials

Critical Care ◽  
2021 ◽  
Vol 25 (1) ◽  
Author(s):  
Rosanna Vaschetto ◽  
Alessandro Pecere ◽  
Gavin D. Perkins ◽  
Dipesh Mistry ◽  
Gianmaria Cammarota ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Randomized Controlled Trials ◽  
Noninvasive Ventilation ◽  
Individual Patient Data ◽  
Meta Analysis ◽  
Invasive Mechanical Ventilation ◽  
Patient Data ◽  
Controlled Trials ◽  
Early Extubation ◽  
Randomized Controlled

Abstract Background Usefulness of noninvasive ventilation (NIV) in weaning patients with non-hypercapnic hypoxemic acute respiratory failure (hARF) is unclear. The study aims to assess in patients with non-hypercapnic hARF, the efficacy of NIV after early extubation, compared to standard weaning. Methods In this individual patient data meta-analysis, we searched EMBASE, Medline and Cochrane Central Register of Controlled Trials to identify potentially eligible randomized controlled trials published from database inception to October 2020. To be eligible, studies had to include patients treated with NIV after early extubation and compared to conventional weaning in adult non-hypercapnic hARF patients. Anonymized individual patient data from eligible studies were provided by study investigators. Using one-step and two-step meta-analysis models we tested the difference in total days spent on invasive ventilation. Results We screened 1605 records. Six studies were included in quantitative synthesis. Overall, 459 participants (mean [SD] age, 62 [15] years; 269 [59%] males) recovering from hARF were included in the analysis (233 in the intervention group and 226 controls). Participants receiving NIV had a shorter duration of invasive mechanical ventilation compared to control group (mean difference, − 3.43; 95% CI − 5.17 to − 1.69 days, p < 0.001), a shorter duration of total days spent on mechanical ventilation (mean difference, − 2.04; 95% CI − 3.82 to − 0.27 days, p = 0.024), a reduced risk of ventilatory associated pneumonia (odds ratio, 0.24; 95% CI 0.08 to 0.71, p = 0.014), a reduction of time spent in ICU (time ratio, 0.81; 95% CI 0.68 to 0.96, p = 0.015) and in-hospital (time ratio, 0.81; 95% CI 0.69 to 0.95, p = 0.010), with no difference in ICU mortality. Conclusions Although primary studies are limited, using an individual patient data metanalysis approach, NIV after early extubation appears useful in reducing total days spent on invasive mechanical ventilation. Trial registration The protocol was registered to PROSPERO database on 12/06/2019 and available at PROSPERO website inserting the study code i.e., CRD42019133837.

scholarly journals A guide to do randomized controlled trials in the field of otolaryngology

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Sameh M. Zamzam ◽  
Mosaad Abdel-Aziz ◽  
Ahmed Atef ◽  
Usama Abdel-Naseer ◽  
Mostafa Hamoda ◽  
...  
Keyword(s):  
Randomized Controlled Trials ◽  
Study Groups ◽  
Controlled Trials ◽  
Main Body ◽  
Main Research ◽  
Randomized Controlled ◽  
New Treatment ◽  
Meta Analyses ◽  
Based Medicine

Abstract Background Randomized controlled trials (RCTs) are prospective comparative studies in which study groups are allocated randomly to intervention or serve as controls. RCT is the mainstay to achieve evidence in the literature in clinical research. A RCT is the main research design to study the effect of an intervention and the only way to confirm the value of a new treatment. Main body RCT also gives the way to generate meta-analyses and systematic reviews giving a stronger evidence for clinical practice. Evidence-based medicine (EBM) is crucial for safe, effective, and standardized patient care. Although there is an agreement on the importance of performing RCT, it can be challenging to do it efficiently including different aspects like study design, funding, randomization, blinding, follow-up, data analysis, statistics, generalization of results, and reporting of quality of the studies. Conclusion In this article, we gave a comprehensive review for RCT in otolaryngology discussing their importance, advantages, and drawbacks, types, steps, challenges, reporting their quality and their prevalence in the literature.

Sign in / Sign up

Export Citation Format

Share Document