scholarly journals An empirical comparison of Bayesian modelling strategies for missing binary outcome data in network meta-analysis

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Loukia M. Spineli
2015 ◽  
Vol 34 (12) ◽  
pp. 2062-2080 ◽  
Author(s):  
N. L. Turner ◽  
S. Dias ◽  
A. E. Ades ◽  
N. J. Welton

2019 ◽  
Vol 22 (4) ◽  
pp. 153-160 ◽  
Author(s):  
Sara Balduzzi ◽  
Gerta Rücker ◽  
Guido Schwarzer

ObjectiveMeta-analysis is of fundamental importance to obtain an unbiased assessment of the available evidence. In general, the use of meta-analysis has been increasing over the last three decades with mental health as a major research topic. It is then essential to well understand its methodology and interpret its results. In this publication, we describe how to perform a meta-analysis with the freely available statistical software environment R, using a working example taken from the field of mental health.MethodsR package meta is used to conduct standard meta-analysis. Sensitivity analyses for missing binary outcome data and potential selection bias are conducted with R package metasens. All essential R commands are provided and clearly described to conduct and report analyses.ResultsThe working example considers a binary outcome: we show how to conduct a fixed effect and random effects meta-analysis and subgroup analysis, produce a forest and funnel plot and to test and adjust for funnel plot asymmetry. All these steps work similar for other outcome types.ConclusionsR represents a powerful and flexible tool to conduct meta-analyses. This publication gives a brief glimpse into the topic and provides directions to more advanced meta-analysis methods available in R.


2021 ◽  
Author(s):  
Loukia Spineli

Abstract Background: To illustrate the advantages of using network meta-analysis (NMA) as compared to a trial or a pairwise meta-analysis to estimate the amount of missing outcome data (MOD) for a target comparison in order to adjust the required sample size for possible participant losses in a future trial.Methods: We introduced the concept of transitive risks to obtain the absolute risks of MOD for all interventions of the network. We used the network of a published systematic review on a binary outcome to apply the proposed concept and to calculate the required sample size in a future trial for a selected target comparison. For that comparison, we also calculated the required sample size using the corresponding trials separately, and after pooling these trials in a random-effects meta-analysis. Results: Ignoring MOD from the sample size calculation led to the smallest sample size. When either trial was considered, the risk of MOD ranged from 1% to 13% in the compared intervention arms, therefore, increasing the sample size from 1% to 12%. Performing a pairwise meta-analysis yielded a risk of MOD equal to 6% and 9% in the active and control arms, respectively, which inflated the sample size by 8%. Using NMA, the corresponding risks of MOD were 10% and 13%, which increased the sample size by 13%. Conclusions: Provided that the transitivity assumption holds, incorporating the absolute risks of MOD in the sample size calculation for a target comparison of the network led to better planning of a future trial.


PEDIATRICS ◽  
1996 ◽  
Vol 97 (2) ◽  
pp. 287-287 ◽  
Author(s):  
ELLEN R. WALD

Dr Bonadio has combined outcome data from four prospective, randomized, double-blind, placebo-controlled trials assessing the effect of adjunctive corticosteroid therapy on the outcome of bacterial meningitis in children treated with a third-generation cephalosporin. Similar to the previously published meta-analysis included in the article by Schaad et al, Dr Bonadio's analysis includes all etiologies of bacterial meningitis without clarifying whether a beneficial effect applies to particular bacterial species. Fifty-two to 82% of cases in each of the trials were comprised of Haemophilus influenzae type b, a bacterial species that is now a rare cause of meningitis in the United States.


EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
D Khanra ◽  
A Mukherjee ◽  
S Deshpande ◽  
D Padmanabhan ◽  
S Mohan ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation in the setting of persistent AF (PeAF) with heart failure (HF) is challenging and often has poor outcome. However, guideline and studies indicate ablation strategy in this group to reduce mortality and HF-related hospitalization. Purpose We have conducted a network meta-analysis (NMA) of all-cause mortality and improvement of HF-related QOL in patients of PeAF with systolic heart failure comparing  rate controlling drugs (RCDs), anti-arrhythmic drugs (AAD), catheter ablation (CA) of PeAF and AV nodal ablation with univentricular or biventricular pacing (AVNA). Method Bayesian network meta-analysis of randomized controlled studies comparing mortality and QOL among individual treatment arms (e.g. RCDs, AADs, CA and AVNA) and pair-wise network meta-analysis comparing CA and other treatment arms (RCD, AAD and AVNA) were performed using MetInsight V3.  Markov chain Monte Carlo (MCMC) modeling was used to estimate the relative ranking probability of each treatment group. Results Published data of 14 studies including 3698 patients were included in the NMA with a median follow-up of two years (1A, 2A). The Bayesian modelling with MCMC analysis for pair-wise comparison clearly demonstrated that, AAD [OR (95% CrI): 2.10 (0.43-9.0)], AVNA [OR (95% CrI): 1.32 (0.14-11.7)] and RCDs [OR (95% CrI): 2.76 (0.5-14.1)] have higher all-cause mortality than CA but not within the radar of statistical significance (1B). The Bayesian modelling with MCMC analysis for pair-wise comparison clearly demonstrated that, AADs [MD (95% CrI): 8.02 (-8.32-27.8)], AVNA [MD (95% CrI): 17.0 (-1.9-33.1)] and RCDs [MD (95% CrI): 13.0 (0.1-24.5)] have lesser improvement in QOL than CA but not within the radar of statistical significance (2B). Based on the Bayesian model, CA results in lower all-cause mortality and highest improvement of QOL in the patients of AF with HF (3A, 3B). Conclusion This shapes way for future treatment guidelines in patients with PeAF with HF group and points towards CA to be undertaken before medical therapy fails. This also paves way for further research to confirm the longevity of the beneficial effects and to find the specific subsets of AF with HF patients that would be benefited most from CA. Abstract Figure


2019 ◽  
Vol 34 (7) ◽  
pp. 433-444
Author(s):  
Thomas M Aherne ◽  
Mekki Medani ◽  
Shaheel Sahebally ◽  
Elrasheid Kheirelseid ◽  
Edward Mulkern ◽  
...  

Background In recent years, endovenous intervention has emerged as a minimally invasive alternative to open venous surgery. However, endovenous intervention does not formally disconnect the deep and superficial venous systems and it is hypothesized that recurrence may be greater in the absence of high venous ligation. This study aims to compare the efficacy of a hybrid endovenous approach with adjuvant high venous ligation and standard operative intervention in the management of great saphenous incompetence. Methods In March 2018, Medline and Embase were systematically searched for relevant randomized controlled trials. All randomized controlled trials comparing a hybrid approach with standard operative intervention were included. Studies were required to include at least one pre-defined outcome. Data were extracted and assessed by two independent reviewers. Pooled risk ratios were calculated using a random effects model. Additional subgroup analyses were performed. Results Eight randomized controlled trials including 1244 patients were analysed. Pooled standardized data revealed no difference in overall recurrence (pooled RR = 1.00 [95% CI = 0.57, 1.77]), major operative morbidity (RR = 0.43 [95% CI = 0.06, 2.89]), or re-interventions (RR = 0.94 [95% CI = 0.12, 7.24]) for the hybrid group compared with standard operative intervention alone. Subgroup analysis revealed comparable short-, medium- and long-term recurrence rates between both cohorts. Furthermore, no difference in recurrence was identified when the hybrid approach was compared to open surgery alone (RR = 1.01 [95% CI = 0.63, 1.61]) or endovenous monotherapy (RR = 0.67 [95% CI = 0.04, 12.24]). Conclusion The use of a hybrid approach in the management of great saphenous incompetence appears to offer no recurrence, re-intervention or morbidity benefit when compared to standard operative intervention.


2021 ◽  
Vol 8 ◽  
Author(s):  
Jie Zhang ◽  
Xingshun Qi ◽  
Fangfang Yi ◽  
Rongrong Cao ◽  
Guangrong Gao ◽  
...  

Background and Aims: The intersphincteric resection (ISR) is beneficial for saving patients' anus to a large extent and restoring original bowel continuity. Laparoscopic ISR (L-ISR) has its drawbacks, such as two-dimensional images, low motion flexibility, and unstable lens. Recently, da Vinci robotic ISR (R-ISR) is increasingly used worldwide. The purpose of this article is to compare the feasibility, safety, oncological outcomes, and clinical efficacy of R-ISR vs. L-ISR for low rectal cancer.Methods: PubMed, EMBASE, Cochrane Library, and Web of Science were searched to identify comparative studies of R-ISR vs. L-ISR. Demographic, clinical, and outcome data were extracted. Mean difference (MD) and risk ratio (RR) with their corresponding confidence intervals (CIs) were calculated.Results: Five studies were included. In total, 510 patients were included, of whom 273 underwent R-ISR and 237 L-ISR. Compared with L-ISR, R-ISR has significantly lower estimated intraoperative blood loss (MD = −23.31, 95% CI [−41.98, −4.64], P = 0.01), longer operative time (MD = 51.77, 95% CI [25.68, 77.86], P = 0.0001), hospitalization days (MD = −1.52, 95% CI [−2.10, 0.94], P < 0.00001), and postoperative urinary complications (RR = 0.36, 95% CI [0.16, 0.82], P = 0.02).Conclusions: The potential benefits of R-ISR are considered as a safe and feasible alternative choice for the treatment of low rectal tumors.


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