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2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Maria Ida Maiorino ◽  
Miriam Longo ◽  
Lorenzo Scappaticcio ◽  
Giuseppe Bellastella ◽  
Paolo Chiodini ◽  
...  

Abstract Background Besides providing reassurance about cardiovascular (CV) safety of newer diabetes drugs, cardiovascular outcome trials (CVOTs) have also shown encouraging benefits on some CV endpoints. The contribution of the better glycemic control in the reduction of major cardiovascular events (MACE) remains an open question. The aim of this study is to evaluate the associations between the reduction of HbA1c and risk of MACE, MACE components, hospitalization for heart failure (HF) and all-cause death in CVOTs. Methods An electronic search up to July 2021 was conducted to determine eligible trials. Systematic review identified eighteen CVOTs reporting prespecified CV outcomes. Pooled summary estimates and 95% confidence intervals (CI) were calculated according to the random effects model using the Paule-Mandel method; restricted maximum likelihood estimators were used to estimate model parameters in the metaregression. Results The eighteen CVOTs evaluated 161,156 patients and included four trials with dipeptidyl-peptidase-4 inhibitors (DPP-4i), eight trials with glucagon-like peptide-1 receptor agonists (GLP-1RA) and six trials with sodium-glucose cotransporter-2 inhibitors (SGLT-2i). Random-effects model meta-analysis showed an association between treatment and risk of MACE (hazard ratio [HR] 0.90; 95% CI 0.86, 0.94, P < 0.001), with significant heterogeneity between studies (I2 = 45.2%, Q statistic P = 0.040). In meta-regression, there was an association between the reduction in HbA1c at the end of the trial and the HR reduction for MACE (beta =  − 0.298, P = 0.007), with significant heterogeneity (I2 = 40%, Q statistic P = 0.04); this association was totally driven by the risk reduction of non-fatal stroke, which explained 100% of between-study variance (beta =  − 0.531, R2 = 100%), without heterogeneity (I2 = 24%, Q statistic P = 0.206). There was no association between the reduction in HbA1c and the HR for heart failure or all-cause death. Conclusions The reduction of HbA1c in eighteen CVOTs was significantly associated with reduction of non-fatal stroke, explaining all (R2 = 100%) of the between-study variance. While the contribution of glucose lowering in some CV benefits of newer agents does not influence their indications for the patient with type 2 diabetes, it may hopefully facilitate their use.


Author(s):  
M. Ocholi ◽  
B. Adeyemi ◽  
O.O. Omojola ◽  
C.S. Samuel

The solar radiation data taken from 14 meteorological stations in Nigeria has been analyzed. The periodic component of the data which covered a period of 13 (mostly 1977-1989) years was removed via Fourier analysis while the residual series was subjected to autoregressive analysis. It was evident from the t-test and autocorrelation plots of the modified (i.e. without the periodic component) series that there exist significant persistence at nine stations including Sokoto, Nguru, Kano, Maiduguri, Bauchi, Yola, Minna, Ibadan, and Benin. The autocorrelation at Jos, Bida, Ikeja, Enugu and Port Harcourt were however found to be insignificant. As the sample partial autocorrelation function cuts off after lag 1, a non-seasonal autoregressive model of order 1, AR (1), was identified for stations with autocorrelation. The Q-statistic of error series suggested that the models were adequate as identified. Moreover, the exploratory plots of the model residual series showed agreement with the quantitative statistics and thus enforces the inference that the models were adequate for monthly mean daily global solar radiation forecasts at some of the study stations. It is interesting to note that all the stations within the sub-sahelian region showed significant persistence whereas all the stations in the coastal region except Benin were found with insignificant autocorrelation. Expectedly, the performance evaluation of the model gave impressive result for the stations within the sub-sahelian region but a relatively weak result for the coastal region. The result for the midland region was mixed whereas it was difficult to conclude on the Guinea savannah region with result from only one station.


Author(s):  
Nur Farhana Mohamed Noor ◽  
Teh Lay Kek ◽  
Mohd Arif Mohd Zim ◽  
Zamzurina Abu Bakar ◽  
Noor Izyani Zakaria ◽  
...  

Background: N-acetyltransferase (NAT2) polymorphisms were reported to play important roles in antituberculosis-induced hepatotoxicity (ATDIH). However, the allelic types with increased risks for ATDIH were inconsistent as most studies are of a small sample size. Objective: The objective of the study was to conduct a meta-analysis to identify NAT2 alleles associated with increased risks of ATDIH. Methods: Studies reported on NAT2 polymorphism with the risk of ATDIH were searched systematically in PubMed, Scopus, and the World of Sciences. Studies were included if they fulfilled the inclusion criteria and excluded accordingly. Quality assessments were done using Newcastle-Ottawa Score. Statistical analysis was performed using Review Manager version 5.3. Cochrane Q-statistic test and I2 statistic were used to assess and quantify heterogeneity. Results: A total of 12 studies involving 580 cases and 3129 controls were included. NAT2 polymorphism was significantly associated with the risk of ATDIH with an odd ratio (OR) of 2.76 (1.86 – 4.10, 95% CI). Among the slow acetylators genotypes, NAT2*5/*7 carry the highest risk associated with ATDIH. Conclusion: NAT2 polymorphism was significantly associated with ATDIH.


PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0256948
Author(s):  
Robera Olana Fite

Background According to the World Health Organization, optimal adherence to Antiretroviral Therapy (ART) improves quality of life. Patients who use ART have varying characteristics in terms of where they live. The effect of place of residence on ART adherence is unclear in Ethiopia. Therefore, the aim of this systematic review and meta-analysis was to estimate the pooled association between place of residence and adherence to ART. Methods Articles were retrieved from PubMed, Scopus, African Journals Online (AJOL), Journal Storage (JSTOR), and Web of Science. The data was extracted using Microsoft Excel 2016 spreadsheet. Review Manager 5.3 and STATA version 14 were used for the analysis. The Cochrane Q statistic was used to assess between-study heterogeneity. I2 was used to quantify between-study heterogeneity. A weighted inverse variance random-effects model was used to calculate the pooled odds ratio with 95% confidence interval. Results Seven studies were included in this systematic review and meta-analysis. The Begg’s test (Z = 0.15, P = 0.881) and Egger’s test (t = 0.14, P = 0.894) revealed no evidence of publication bias. Urban residence was associated with an increased likelihood of good adherence (OR 2.07, 95%CI 1.22–3.51). Conclusions The study recommends that policy-makers should enact policies that increase access to ART services in a rural area in order to improve adherence. It is recommended that implementation studies be conducted in order to identify practical and affordable interventions.


2021 ◽  
Author(s):  
Yan Yu ◽  
Jiasu Liu

Objectives: This meta-analysis aimed to identify the therapeutic effect of 0.01% atropine with on ocular axial elongation for myopia children. Methods: We searched PubMed, Cochrane Library, and CBM databases from inception to July 2021. Meta-analysis was conducted using STATA version 14.0 and Review Manager version 5.3 softwares. We calculated the weighted mean differences(WMD) to analyze the change of ocular axial length (AL) between orthokeratology combined with 0.01% atropine (OKA) and orthokeratology (OA) alone. The Cochran's Q-statistic and I2 test were used to evaluate potential heterogeneity between studies. To evaluate the influence of single studies on the overall estimate, a sensitivity analysis was performed. We also performed sub group and meta-regression analyses to investigate potential sources of heterogeneity. We conducted Begger's funnel plots and Egger's linear regression tests to investigate publication bias. Results: Nine studies that met all inclusion criteria were included in this meta-analysis. A total of 191 children in OKA group and 196 children in OK group were assessed. The pooled summary WMD of AL change was -0.90(95%CI=-1.25~-0.55) with statistical significance(t=-5.03, p<0.01), which indicated there was obvious difference between OKA and OK in myopic children. Subgroup analysis also showed that OKA treatment resulted in significantly less axial elongation compared to OK treatment alone according to SER. We found no evidence for publication bias. Conclusions:  Our meta-analysis indicates 0.01% atropine atropine is effective in slowing axial elongation in myopia children with orthokeratology.


Author(s):  
Linlin Zhang ◽  
Guanghui Qiao ◽  
Huiling Huang ◽  
Yang Chen ◽  
Jiaojiao Luo

Residential sprawl constitutes a main part of urban sprawl which poses a threat to the inhabitant environment and public health. The purpose of this article is to measure the residential sprawl at a micro-scale using a case study of Hangzhou city. An integrated sprawl index on each 1 km × 1 km residential land cell was calculated based on multi-dimensional indices of morphology, population density, land-use composition, and accessibility, followed by a dynamic assessment of residential sprawl. Furthermore, the method of GeoDetector modeling was applied to investigate the potential effects of location, urbanization, land market, and planning policy on the spatial variation of residential sprawl. The results revealed a positive correlation between CO2 emissions and residential sprawl in Hangzhou. There has been a remarkable increase of sprawl index on residential land cells across the inner suburb and outer suburb, and more than three-fifths of the residential growth during 2000–2010 were evaluated as dynamic sprawl. The rapid development of the land market and urbanization were noted to impact the spatiotemporal distribution of residential sprawl, as q-statistic values of population growth and land price ranked highest. Most notably, the increasing q-statistic values of urban planning and its significant interactions with other factors highlighted the effects of incremental planning policies. The study derived the policy implication that it is necessary to transform the traditional theory and methods of incremental planning.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jie Xu ◽  
Wenwei Xiao ◽  
Xuan Liang ◽  
Li Shi ◽  
Peihua Zhang ◽  
...  

Abstract Background Cardiovascular disease (CVD), one of the most common comorbidities of coronavirus disease 2019 (COVID-19), has been suspected to be associated with adverse outcomes in COVID-19 patients, but their correlation remains controversial. Method This is a quantitative meta-analysis on the basis of adjusted effect estimates. PubMed, Web of Science, MedRxiv, Scopus, Elsevier ScienceDirect, Cochrane Library and EMBASE were searched comprehensively to obtain a complete data source up to January 7, 2021. Pooled effects (hazard ratio (HR), odds ratio (OR)) and the 95% confidence intervals (CIs) were estimated to evaluate the risk of the adverse outcomes in COVID-19 patients with CVD. Heterogeneity was assessed by Cochran’s Q-statistic, I2test, and meta-regression. In addition, we also provided the prediction interval, which was helpful for assessing whether the variation across studies was clinically significant. The robustness of the results was evaluated by sensitivity analysis. Publication bias was assessed by Begg’s test, Egger’s test, and trim-and-fill method. Result Our results revealed that COVID-19 patients with pre-existing CVD tended more to adverse outcomes on the basis of 203 eligible studies with 24,032,712 cases (pooled ORs = 1.41, 95% CIs: 1.32-1.51, prediction interval: 0.84-2.39; pooled HRs = 1.34, 95% CIs: 1.23-1.46, prediction interval: 0.82-2.21). Further subgroup analyses stratified by age, the proportion of males, study design, disease types, sample size, region and disease outcomes also showed that pre-existing CVD was significantly associated with adverse outcomes among COVID-19 patients. Conclusion Our findings demonstrated that pre-existing CVD was an independent risk factor associated with adverse outcomes among COVID-19 patients.


2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Mengtong Wu ◽  
Chao Jiang ◽  
Yi Zhang ◽  
Jingjing Cao ◽  
Ying Cheng ◽  
...  

AbstractCulture and distance are two major factors for geographically segmenting tourists in tourism marketing and advertising. Previous empirical studies on the destination image, however, have examined extensively the effect of the culture while inadequately the effect of the distance, let alone comparing the effects of the two variables. Using social media data, this study compares the effect of distance-based segments of tourists with that of culture-based segments in producing diverse perceived images of a destination. From Sina Weibo data, 282,532 Chinese mainland tourists who visited Suzhou, China during 2012–2016 and their perceived destination images are extracted and analyzed. The main results include: 1) for distance-based segments, the image differences increased with distance and the short-haul tourists perceived a more comprehensive image than the long-haul tourists; 2) for culture-based segments, the image differences were clear and relatively complex, while tourists from Wuyue cultural region had similar image perceptions with the local visitors; 3) the q-statistic of the Geodetector method shows that the culture-based segmentation can explain 65.8% of image variations while the distance-based segmentation can explain 46.6% of image variations, suggesting that culture is a more appropriate variable to segment the tourism market.


2021 ◽  
Author(s):  
Jyotim Gogoi ◽  
Kennedy Ningthoujam

Abstract Spiders are the Arthropod and belong to the Phylum: Arthropoda, Class: Arachnida, Order: Araneae. Their occurrence worldwide is about 30,000 species belonging to the 60 families. Totally 4023 arthropods were collected from Silvicultural, Horticultural and Agricultural ecosystem (Maize, Potato and Rice) which belonged to 14 orders and 85 Nos. of different families. Among the ecosystem maximum diversity found in Silvicultural followed by Horticultural and Agricultural ecosystem in terms of alpha diversity such as Shannon Wiener index Simpsons D, Species number, Margelef D, Equitability J, Berger Parker index, Maclntosch U, Brillouin level, Fisher Alpha, Q Statistic and beta diversity such as Whittaker Bw, Cody Bc, Routledge Br, Routledge Bi, Routledge Be and Wilson & Shmida Bt.


2021 ◽  
Vol 3 (1) ◽  
pp. 18-41
Author(s):  
Agya Atabani Adi ◽  
Amadi W. Kingsley ◽  
David Vincent Hassan

This paper employed variant GARCH models to examined official, interbank and Bureau de change returns volatilities. Using monthly exchange rate of Naira/USD from January 2004 to September 2020 (2004:1-2020:9), the returns were not normally distributed and stationary at level. Ljung-Box Q statistic and Ljung-Box Q2 statistics of power transformed using power 0.25, 0.5 and 0.75 for conditional heteroscedasticity for lags of 6, 12 and 20 indicated present of conditional heteroscedascity in all returns. The study found exchange rate volatility in Official, interbank and Bureau de change exchange rate returns were persistent. However, Bureau de change return was more persistent while official exchange rate return was the least persistent. Also, leverage effect exist in all the three exchange rate returns and asymmetric model were the best model for estimating exchange rate return while IGARCH was the worst model to estimate exchange rate return in Nigeria. There is need to incorporate news impact when developing exchange rate policy by monetary authority in Nigeria.


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