scholarly journals Individual Participant Data Meta-Analysis of Foliar Fungicides Applied for Potato Early Blight Management

Plant Disease ◽  
2016 ◽  
Vol 100 (1) ◽  
pp. 200-206 ◽  
Author(s):  
S. K. R. Yellareddygari ◽  
Julie S. Pasche ◽  
Raymond J. Taylor ◽  
Neil C. Gudmestad

Foliar fungicides continue to be the primary means of early blight management on potato in the United States. Both premium-priced, single-site mode-of-action “specialty” fungicides and standard protectant multisite fungicides are applied, either alone or incorporated into fungicide rotation programs to combat early blight. Individual participant data meta-analysis was conducted to compare overall fungicide efficacy against early blight on potato, quantify tuber yields, and identify the most efficacious timing for fungicide applications. In this study, the specialty fungicide-based applications were compared against the standard fungicides chlorothalonil and mancozeb applied alone. Type 3 fixed effects indicated that there was a significant difference (P < 0.0001) in overall efficacy and yield among the treatments applied to manage early blight in potato. There was a significant difference (P < 0.0001) among treatments in early blight development during the growing season. Applications incorporating specialty fungicides, when compared with standard fungicides, significantly affected disease severity from vegetative growth initiation (P = 0.0139) to tuber maturation (P = 0.0009). Results demonstrate that the higher cost, specialty-fungicide-based applications were most effective for early blight management in North Dakota and Minnesota.

2019 ◽  
Vol 23 (25) ◽  
pp. 1-98 ◽  
Author(s):  
Rod S Taylor ◽  
Sarah Walker ◽  
Oriana Ciani ◽  
Fiona Warren ◽  
Neil A Smart ◽  
...  

Background Current national and international guidelines on the management of heart failure (HF) recommend exercise-based cardiac rehabilitation (ExCR), but do not differentiate this recommendation according to patient subgroups. Objectives (1) To obtain definitive estimates of the impact of ExCR interventions compared with no exercise intervention (control) on mortality, hospitalisation, exercise capacity and health-related quality of life (HRQoL) in HF patients; (2) to determine the differential (subgroup) effects of ExCR in HF patients according to their age, sex, left ventricular ejection fraction, HF aetiology, New York Heart Association class and baseline exercise capacity; and (3) to assess whether or not the change in exercise capacity mediates for the impact of the ExCR on final outcomes (mortality, hospitalisation and HRQoL), and determine if this is an acceptable surrogate end point. Design This was an individual participant data (IPD) meta-analysis. Setting An international literature review. Participants HF patients in randomised controlled trials (RCTs) of ExCR. Interventions ExCR for at least 3 weeks compared with a no-exercise control, with 6 months’ follow-up. Main outcome measures All-cause and HF-specific mortality, all-cause and HF-specific hospitalisation, exercise capacity and HRQoL. Data sources IPD from eligible RCTs. Review methods RCTs from the Exercise Training Meta-Analysis of Trials for Chronic Heart Failure (ExTraMATCH/ExTraMATCH II) IPD meta-analysis and a 2014 Cochrane systematic review of ExCR (Taylor RS, Sagar VA, Davies EJ, Briscoe S, Coats AJ, Dalal H, et al. Exercise-based rehabilitation for heart failure. Cochrane Database Syst Rev 2014;4:CD003331). Results Out of the 23 eligible RCTs (4398 patients), 19 RCTs (3990 patients) contributed data to this IPD meta-analysis. There was a wide variation in exercise programme prescriptions across included studies. Compared with control, there was no statistically significant difference in pooled time-to-event estimates in favour of ExCR, although confidence intervals (CIs) were wide: all-cause mortality had a hazard ratio (HR) of 0.83 (95% CI 0.67 to 1.04); HF-related mortality had a HR of 0.84 (95% CI 0.49 to 1.46); all-cause hospitalisation had a HR of 0.90 (95% CI 0.76 to 1.06); and HF-related hospitalisation had a HR of 0.98 (95% CI 0.72 to 1.35). There was a statistically significant difference in favour of ExCR for exercise capacity and HRQoL. Compared with the control, improvements were seen in the 6-minute walk test (6MWT) (mean 21.0 m, 95% CI 1.57 to 40.4 m) and Minnesota Living with Heart Failure Questionnaire score (mean –5.94, 95% CI –1.0 to –10.9; lower scores indicate improved HRQoL) at 12 months’ follow-up. No strong evidence for differential intervention effects across patient characteristics was found for any outcomes. Moderate to good levels of correlation (R 2 trial > 50% and p > 0.50) between peak oxygen uptake (VO2peak) or the 6MWT with mortality and HRQoL were seen. The estimated surrogate threshold effect was an increase of 1.6 to 4.6 ml/kg/minute for VO2peak. Limitations There was a lack of consistency in how included RCTs defined and collected the outcomes: it was not possible to obtain IPD from all includable trials for all outcomes and patient-level data on exercise adherence was not sought. Conclusions In comparison with the no-exercise control, participation in ExCR improved the exercise and HRQoL in HF patients, but appeared to have no effect on their mortality or hospitalisation. No strong evidence was found of differential intervention effects of ExCR across patient characteristics. VO2peak and 6MWT may be suitable surrogate end points for the treatment effect of ExCR on mortality and HRQoL in HF. Future studies should aim to achieve a consensus on the definition of outcomes and promote reporting of a core set of HF data. The research team also seeks to extend current policies to encourage study authors to allow access to RCT data for the purpose of meta-analysis. Study registration This study is registered as PROSPERO CRD42014007170. Funding The National Institute for Health Research Health Technology Assessment programme.


2022 ◽  
Author(s):  
José M. Causadias ◽  
Kevin Michael Korous ◽  
Karina M Cahill ◽  
Eiko I Fried ◽  
Longfeng Li

Although a growing body of research has documented racial/ethnic disparities in depressive symptoms in the United States, the precise magnitude of these differences is not known. We conducted a systematic review and meta-analysis of individual participant data to (1) estimate the average difference of depressive symptoms between Whites and racial/ethnic minorities, as well as differences between (i.e., Asian American, African American, Latinxs, Multiracial, Native American, other race) and within (i.e., Latinx: Central American, Cuban American, Mexican American, Puerto Rican, other Latinx) minority groups, and (2) determine if moderators account for these differences. We screened 2,425 nationally-representative studies from the Inter-university Consortium for Political and Social Research (ICPSR), and identified 127 datasets of studies conducted from 1971 to 2018. We included 73 datasets from 26 nationally-representative studies (N = 2,116,853). The average absolute difference was d = 0.09, 95% CI [0.07, 0.12] between White and minority participants; was d = 0.07, 95% CI [0.06, 0.09] between minority participants; and d = 0.10, 95% CI [0.06, 0.15] within minority Latinx participants. Increases in socioeconomic status exacerbated these disparities. Psychometric analyses showed that measure reliability was related to larger differences. We discuss the implications of these findings.


Author(s):  
Cynthia Huber ◽  
Norbert Benda ◽  
Tim Friede

AbstractModel-based recursive partitioning (MOB) can be used to identify subgroups with differing treatment effects. The detection rate of treatment-by-covariate interactions and the accuracy of identified subgroups using MOB depend strongly on the sample size. Using data from multiple randomized controlled clinical trials can overcome the problem of too small samples. However, naively pooling data from multiple trials may result in the identification of spurious subgroups as differences in study design, subject selection and other sources of between-trial heterogeneity are ignored. In order to account for between-trial heterogeneity in individual participant data (IPD) meta-analysis random-effect models are frequently used. Commonly, heterogeneity in the treatment effect is modelled using random effects whereas heterogeneity in the baseline risks is modelled by either fixed effects or random effects. In this article, we propose metaMOB, a procedure using the generalized mixed-effects model tree (GLMM tree) algorithm for subgroup identification in IPD meta-analysis. Although the application of metaMOB is potentially wider, e.g. randomized experiments with participants in social sciences or preclinical experiments in life sciences, we focus on randomized controlled clinical trials. In a simulation study, metaMOB outperformed GLMM trees assuming a random intercept only and model-based recursive partitioning (MOB), whose algorithm is the basis for GLMM trees, with respect to the false discovery rates, accuracy of identified subgroups and accuracy of estimated treatment effect. The most robust and therefore most promising method is metaMOB with fixed effects for modelling the between-trial heterogeneity in the baseline risks.


BMJ Open ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. e039518
Author(s):  
Jack Michael Birch ◽  
Simon J Griffin ◽  
Michael P Kelly ◽  
Amy L Ahern

IntroductionIt has been suggested that interventions focusing on individual behaviour change, such as behavioural weight management interventions, may exacerbate health inequalities. These intervention-generated inequalities may occur at different stages, including intervention uptake, adherence and effectiveness. We will synthesise evidence on how different measures of inequality moderate the uptake, adherence and effectiveness of behavioural weight management interventions in adults.Methods and analysisWe will update a previous systematic literature review from the United States Preventive Services Taskforce to identify trials of behavioural weight management interventions in adults aged 18 years and over that were, or could feasibly be, conducted in or recruited from primary care. Medline, Cochrane database (CENTRAL) and PsycINFO will be searched. Only randomised controlled trials (RCTs) and cluster-RCTs will be included. Two investigators will independently screen articles for eligibility and conduct risk of bias assessment. We will curate publication families for eligible trials. The PROGRESS-Plus acronym (place of residence, race/ethnicity, occupation, gender, religion, education, socioeconomic status, social capital, plus other discriminating factors) will be used to consider a comprehensive range of health inequalities. Data on trial uptake, intervention adherence, weight change and PROGRESS-Plus-related data will be extracted. Data will be synthesised narratively. We will present a Harvest plot for each PROGRESS-Plus criterion and whether each trial found a negative, positive or no health inequality gradient. We will also identify potential sources of unpublished original research data on these factors which can be synthesised through a future individual participant data meta-analysis.Ethics and disseminationEthical approval is not required as no primary data are being collected. The completed systematic review will be disseminated in a peer-reviewed journal, at conferences, and contribute to the lead author’s PhD thesis. Authors of trials included in the completed systematic review may be invited to collaborate on a future individual participant data meta-analysis.PROSPERO registration numberCRD42020173242.


2018 ◽  
Author(s):  
José M. Causadias ◽  
Kevin Michael Korous ◽  
Karina M Cahill ◽  
Eiko I Fried ◽  
Longfeng Li

A growing body of research has documented racial disparities in depressive symptoms in the United States, although the precise magnitude on these differences is less well understood. This issue has important implications for informing public health policy, and developing and administering prevention and intervention strategies. In this protocol, we propose a systematic review and meta-analysis of individual participant data from nationally representative studies from the United States drawn from Inter-university Consortium for Political and Social Research (ICPSR). Our three aims are to: 1) Estimate the overall average difference of depressive symptoms between Whites and minorities, as well as between- (e.g., African-Americans, Latinos) and within- (e.g., Latinos: Mexican-Americans, Cuban-Americans) minority groups; 2) Determine if age, sex, education, income, occupation, socioeconomic status, and other variables account for these differences; 3) Test the cultural differences and similarities hypotheses. We argue that these health disparities are the result of social inequalities.


BMJ ◽  
2014 ◽  
Vol 348 (jun17 16) ◽  
pp. g3656-g3656 ◽  
Author(s):  
B. Schottker ◽  
R. Jorde ◽  
A. Peasey ◽  
B. Thorand ◽  
E. H. J. M. Jansen ◽  
...  

Author(s):  
Mohamed Elfil ◽  
Mohamed Elfil ◽  
Mohammad Aladawi ◽  
Mohamed Eldokmak ◽  
Ahmed Bayoumi ◽  
...  

Introduction : Mechanical thrombectomy (MT) has become the standard treatment of acute ischemic stroke (AIS) caused by large vessel occlusion (LVO), with different techniques used to achieve revascularization of the occluded vessel. However, early re‐occlusion of the target vessels could still take place in a considerable proportion of patients who already underwent MT for LVO. Therefore, we conducted this systematic review and individual participant data (IPD) meta‐analysis to provide more comprehensive evidence regarding the efficacy of repeat thrombectomy for recurrent LVO in early after successful first‐time MT. Methods : A computerized search on MEDLINE via PubMed, SCOPUS, Web of Science, EMBASE, and Cochrane library using the relevant keywords was performed. The retrieved references were screened, and the relevant data were extracted. STATA and SPSS were used to perform this IPD meta‐analysis. Results : Twenty studies were included, of which ten studies were observational studies (n = 21,251 patients) and 10 cases reports (n = 10 patients). Out of the included patients, 266 patients (62.78% females) were identified with recurrent LVO. The overall prevalence of recurrent LVO was 1.6%, 95% CI (1.0% to 2.8%), p<0.001. The mean age of the included patients was 65.67±16.23 years. Cardiac embolism was the most common cause of stroke in both times (52%). The median number of days between the first and second LVO was 15 days (IQR: 4–191). Regarding the National Institute of Health Stroke Scale (NIHSS), the first and second MT reduced it significantly (MD = ‐8.91, 95% CI: ‐10.02 to ‐7.82) and (MD = ‐5.97, 95% CI: ‐7.53 to ‐4.43), respectively, with a significant difference between both procedures (p = 0.001). The mean ASPECT after the first MT was 8.65±1.45, and after the second MT was 8.01±1.88. A significant weak correlation was observed between the ASPECT of first MT and NIHSS before it (r = ‐0.270, p = 0.001). Based on the thrombolysis in cerebral infarction (TICI) grading system, the first MT resulted in 57.3% complete perfusion, 42.1% partially filling, and 0.7% no/minimal filling, while the second MT resulted in 48% complete perfusion, 30% partially filling, and 6.67% no/minimal filling, with a significant difference between both MTs (p = 0.042). Regarding the modified Rankin scale (mRS) at 90 days after the first MT, “0” was the most frequent outcome (26.9%), followed by “2” (13.0%), “1” (12.4%), and “4” (7.3%). On the other hand, the 90‐day mRS after the second MT was categorized as the following: “6” in 13.5%, “3” in 13.5%, “2” in 11.9%, “1” in 11.9%, and “4” in 9.3%. Conclusions : In properly selected patients with recurrent LVO, repeated MT appears to be feasible and safe. A prior MT procedure should not discourage aggressive treatment as these patients may achieve similar rates of good clinical outcomes as those who undergo single MT.


2019 ◽  
Vol 189 (4) ◽  
pp. 343-353 ◽  
Author(s):  
Gergő Baranyi ◽  
Stefan Sieber ◽  
Stéphane Cullati ◽  
Jamie R Pearce ◽  
Chris J L Dibben ◽  
...  

Abstract Although residential environment might be an important predictor of depression among older adults, systematic reviews point to a lack of longitudinal investigations, and the generalizability of the findings is limited to a few countries. We used longitudinal data collected between 2012 and 2017 in 3 surveys including 15 European countries and the United States and comprising 32,531 adults aged 50 years or older. The risk of depression according to perceived neighborhood disorder and lack of social cohesion was estimated using 2-stage individual-participant-data meta-analysis; country-specific parameters were analyzed by meta-regression. We conducted additional analyses on retired individuals. Neighborhood disorder (odds ratio (OR) = 1.25) and lack of social cohesion (OR = 1.76) were significantly associated with depression in the fully adjusted models. In retirement, the risk of depression was even higher (neighborhood disorder: OR = 1.35; lack of social cohesion: OR = 1.93). Heterogeneity across countries was low and was significantly reduced by the addition of country-level data on income inequality and population density. Perceived neighborhood problems increased the overall risk of depression among adults aged 50 years or older. Policies, especially in countries with stronger links between neighborhood and depression, should focus on improving the physical environment and supporting social ties in communities, which can reduce depression and contribute to healthy aging.


Author(s):  
Andrew R. Coggan ◽  
Marissa N. Baranauskas ◽  
Rachel J. Hinrichs ◽  
Ziyue Liu ◽  
Stephen J. Carter

Abstract Background Previous narrative reviews have concluded that dietary nitrate (NO3−) improves maximal neuromuscular power in humans. This conclusion, however, was based on a limited number of studies, and no attempt has been made to quantify the exact magnitude of this beneficial effect. Such information would help ensure adequate statistical power in future studies and could help place the effects of dietary NO3− on various aspects of exercise performance (i.e., endurance vs. strength vs. power) in better context. We therefore undertook a systematic review and individual participant data meta-analysis to quantify the effects of NO3− supplementation on human muscle power. Methods The literature was searched using a strategy developed by a health sciences librarian. Data sources included Medline Ovid, Embase, SPORTDiscus, Scopus, Clinicaltrials.gov, and Google Scholar. Studies were included if they used a randomized, double-blind, placebo-controlled, crossover experimental design to measure the effects of dietary NO3− on maximal power during exercise in the non-fatigued state and the within-subject correlation could be determined from data in the published manuscript or obtained from the authors. Results Nineteen studies of a total of 268 participants (218 men, 50 women) met the criteria for inclusion. The overall effect size (ES; Hedge’s g) calculated using a fixed effects model was 0.42 (95% confidence interval (CI) 0.29, 0.56; p = 6.310 × 10− 11). There was limited heterogeneity between studies (i.e., I2 = 22.79%, H2 = 1.30, p = 0.3460). The ES estimated using a random effects model was therefore similar (i.e., 0.45, 95% CI 0.30, 0.61; p = 1.064 × 10− 9). Sub-group analyses revealed no significant differences due to subject age, sex, or test modality (i.e., small vs. large muscle mass exercise). However, the ES in studies using an acute dose (i.e., 0.54, 95% CI 0.37, 0.71; p = 6.774 × 10− 12) was greater (p = 0.0211) than in studies using a multiple dose regimen (i.e., 0.22, 95% CI 0.01, 0.43; p = 0.003630). Conclusions Acute or chronic dietary NO3− intake significantly increases maximal muscle power in humans. The magnitude of this effect–on average, ~ 5%–is likely to be of considerable practical and clinical importance.


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