To show that a new drug is better than, as good as, or no worse than that of a known effective drug. Theoretically, it is necessary to confirm the efficacy of a treatment, but the current practice of clinical trial suggests that there exists many problems in its confirmation including the objectives of clinical investigation vary based on the fact that more and more clinical trials use active controls. Applied statistical methods have to adapt to these changes. In this paper, we illustrated some statistical issues of confirming efficacy in clinical trials, including its conditions, the determination of clinical margin, the forms of the null and alternative hypothesis and confidence intervals, the choice of endpoints and some miscellaneous considerations. We bly suggests that it is necessary to make biostatisticians and clinical trialists understand the importance of using the right statistical methods when investigating clinical trials. We also think these methods introduced in the paper may provide some help in trial design and evaluation.
ObjectivesTo explore the statistical performance of different methods for meta-analysis of single rates with zero events so as to provide evidence for selecting meta-analysis methods in evidence-based research.MethodsThrough Monte-Carlo simulations, we evaluated the performance of various transformation and correction methods for meta-analysis of single rates with zero events, considering the point estimate bias, confidence interval coverage and width.ResultsWhen the overall event rate was above 30%, all methods showed good statistical performance. As the event rate dropped, log, logit, and arcsine transformations could still maintain good performance. However, when the event rate was less than 5%, only Freeman-Tukey transformation showed excellent performance.ConclusionsThe meta-analysis of single rate based on Freeman-Tukey transformation is robust, and should be recommended as the preferable choice of meta-analysis of single rate with zero events.
ObjectiveTo analyze the current status of the application of randomization methods in randomized controlled trials (RCTs) which have been published in New England Journal of Medicine (NEJM).MethodsRCTs published by NEJM in 2018 were searched and collected. The characteristics of clinical trial design elements and the application status of randomization methods were comprehensively analyzed to distinguish blind trial and non-blind trial, and characteristics of application of randomization methods and selection of allocation concealment mechanisms of non-blind trials were summarized.ResultsA total of 151 RCTs were published in NEJM in 2018, in which blinded trials and non-blinded trials accounted for 75 (49.67%) and 76 (50.33%), respectively. 34 (22.52%) RCTs did not report specific randomization methods, and the remaining 117 (77.48%) reported. Among the latter, stratified block randomization accounted for the main body (72.65%), followed by block randomization (11.11%), minimization method (9.40%), simple randomization method (4.27%) and the others. There was no significant difference in the proportion of reporting or using randomization methods between blind and non-blind trials (P>0.05). In 76 non-blind trials, 38 (50.00%) clearly reported the concealment method of random allocation, among which 37 used the central randomization (97.37%) and 1 used envelope method (2.63%).ConclusionsThe current RCTs published in NEJM still have problems in the selection of randomization methods to be optimized and the transparency of randomization reporting to be improved.
【摘要】目的 观察介入灌注化疗栓塞后手术切除直肠癌的临床疗效。方法 本组31例患者于术前先行区域性动脉灌注化疗加栓塞术，然后多在3～7 d内限期行直肠癌根治术，其中行Dixon术23例， Miles术7例， Hartmann术1例。结果 本组患者术中出血少，肿瘤剥离容易，一般无须输血； 患者术后的肿瘤复发率、转移率和死亡率均优于我科同期术前未行区域性动脉灌注化疗加栓塞术而直接接受手术治疗者。结论 先行区域性动脉灌注化疗栓塞术后再行直肠癌根治性切除，近期疗效好，不失为直肠癌综合治疗的一种新的有效方法。
Objectives To evaluate the reporting quality of Bland-Altman method consistency evaluation in China from 2014 to 2016. Methods WanFang Data, VIP and CNKI databases were electronically searched to collect literature about the application of Bland-Altman method from 2014 to 2016 in China. Two reviewers screened literature, extracted data, and the data were then statistically analyzed by SPSS 22.0 software. Results A total of 376 articles were included. The published articles on Bland-Altman method had major flaws (not conforming to reporting standards) in the application conditions, evaluation indexes, graphic depiction and so on. Merely 11.4% of the literature set the clinically acceptable consensus values in the pre-period studies. Merely one literature (0.3%) correctly compared the 95%CI of 95%LoA with the clinically acceptable threshold which had been set previously. The offer rates of the differences between the two measurements and the 95%CI, 95%LoA and 95%CI of 95%LoA in the figure were 95.9%, 9.5%, 94.6% and 4.4%, respectively. Conclusions The reporting quality of Bland-Altman method consistency evaluation in China is of low quality, specifically not conforming to reporting standards. We should strengthen the introduction of Bland-Altman methodology to improve the reporting quality.