Objective To assess the efficacy and safety of fibfinogen-depleting agents (snake venom extracts) in the treatment of acute ischemic stroke. Method A systematic review of all the relevant randomized controlled trails (RCTs) was performed. RCTs were identified from the Cochrane Stroke Group’s Specialized Trials Register, additional electronic and handsearching, and personal contract with pharmaceutical companies. We included all completed and unconfounded truly or quasi-randomized trials in patients with ischemic stroke comparing fibrinogen depleting agents for analysis. Results Ten completed and one ongoing RCTs have been identified so far. Up to 1998, only three trials using ancrod (182 patients) met the inclusion criteria. Ancrod was associated with a significant reduction in early deaths (5.6% vs. 16%; odds ratio [OR], 0.33; 95% confidence interval [CI], 0.13 to 0.85; 2P=0.02) suggesting that treatment of 100 patients would avoid about 10 early deaths. The frequency of asymptomatic intracranial hemorrhage shown by computed tomography was similar between ancrod-treated and control groups (7.6% vs. 9.6%; OR 0.78; 95%CI 0.26 to 2.33; 2P=0.65). No major intracranial or extracranial hemorrhages or recurrent ischemic strokes occurred in the ancord-allocated patients. There were nonsignificant trends in favor of ancrod in death from any cause (OR 0.57; 95%CI 0.27 to 1.23; 2P=0.15) and death or disability (OR 0.52; 95%CI 0.26 to 1.03; 2P=0.06) at the end of trial follow-up. Up to 2000, other two trials published results. This review will be updated with new trial results soon, which will provide more data. Conclusions There were too few patients and outcome events to draw reliable conclusions from the present data. Although ancrod-like agents appeared promising, their routine use cannot be recommended at the moment. Future trials should test simpler fixed-dose regimens to allow better generalizability.
Objective To assess the effect of different thrombolytic agents, and different regimens in acute ischaemic stroke. Methods A systematic review of all the relevant randomized controlled trials (RCTs) was performed. RCTs were identified from the Cochrane Stroke Group trials register, Embase (1980 to 1997), handsearching Japanese and Chinese journals, and personal contact with pharmaceutical companies. We included randomised and quasi-randomised trials in patients with confirmed acute ischaemic stroke comparing different doses of a thrombolytic agent, or different thrombolytic agent, or the same agent given by different routes. Results Eight trials involving 1 334 patients were included. Concealment of allocation was generally adequate. All the trials were conducted in Japan. Different doses (of tissue plasminogen activator or urokinase) were compared in six trials. Different agents (tissue plasminogen activator versus urokinase,or tissue-cultured urokinase versus conventional urokinase) were compared in three trials. Few data were available for functional outcomes. A higher dose of thrombolytic therapy was associated with a five-fold increase in fatal intracranial haernorrhages (odds ratio 5.02, 95% confidence interval 1.56 to 16.18). There was a non-significant trend towards more early deaths or clinically significant intracranial haemorrhages in higher dose group. No difference in late deaths or extra-cranial haemorrhages was shown between low and higher doses. However, very few of these events occurred. No difference was shown between the different thrombolytic agents tested. Conclusions There is not enough evidence to conclude whether lower doses of thrombolytic agents might be safer or more effective than higher doses in acute ischaemic stroke. It is not possible to conclude whether one agent might be better than another, or which route of administration might be best.
Objective To assess the effects and safety of vasodilators for sudden sensorineurial hearing loss (SSHL). Search strategy Electronic databases: MEDLINE from 1966, EMBASE from 1974, the Cochrane Controlled Trials Register, Chinese Bio-medicine Database from 1989. Hand search: Five kinds of Chinese otolaryngology journals were searched. Literature references were checked intensively. Selection criteria Randomized controlled trials comparing vasodilators with placebo or other drugs in patients with SSHL. Data collection and analysis At least two reviewers independently assessed trials quality and extracted data. Main results Thirteen trials with 1 155 patients were eligible and included in the systematic review. Ten of the trials were from developed countries and them were from P. R. China. None of the four trials showed that the effects of vasodilators were better than placebo for SSHL. None of the seven trials showed that the effects of one kind of vasodilators were better than that of the other vasodilators. Two trials showed that other drugs, such as batroxobin and hypaque,were probably better than some vasodilators (dextran, papaverine, 654-2, danshen). Eight trials reported the side effects of vasodilators, such as pruritus, allergy, etc. Reviewers’ conclusions Base on the systematic review of current eligible randomized controlled trials, there is no evidence to prove that vasodilator therapy is better than placebo or other therapies for SSHL, or the effects of one kind of vasodilator are better than that of the other vasodilators. We can’t draw a reliable conclusion about the effects of vasodilators for SSHL at the moment. And we must pay attention to their potential adverse reactions.
Objective To appraise the current situation of randomized controlled trials (RCTs) on information of common-used digestive-related medicines afforded by medicine-salesmen. Methods RCTs on digestive-related medicines were assessed according to clinical epidemiologic standard. Results 60 medicines containing 252 therapeutic articles were searched and 75 RCTs were identified and assessed. Conclusion The qualities and quantities of RCTs of information on digestive-related medicines were of large difference, the RCTs afforded by the joint pharmaceutical enterprises are much better than those of foreign ones and domestic ones.
Objective To investigate the current situation of randomized controlled trials or clinical controlled trial (RCT/CCT) on chronic hepatitis B and whether to offer reliable evidence for clinical practice in China. Methods RCT/CCT identified from six Chinese clinical journals were searched manually and assessed according to international standard of evidence-based medicine. Results 308 issues containing 212 therapeutic articles and 88 RCT/CCT on chronic hepatitis B were identified and analyzed. Conclusion the quantity and quality of RCT/CCT of chronic hepatitis B did not meet the need of clinical practice.
Objective To evaluate the current situation of randomized controlled trials/ clinical controlled trials (RCT/CCT) on chronic gastritis and whether it could offer reliable evidence for clinical practice in China. Method RCT/CCT on chronic gastritis from eight Chinese clinical journals were searched manually and assessed according to international standard. Results 823 issues containing 213 therapeutic articles were searched and 81 RCT/CCT were identified and assessed. Conclusions The quantity and quality of RCT/CCT on Chronic gastritis in China could not meet the need of clinical practice. RCT/CCT of western medical therapy are much better than those of traditional Chinese therapy and integrated traditional Chinese and western medical therapy ones.
Objective To seek the statistical solution in the comparison of different effects from multi-center randomized controlled trials （RCTs）. Methods The data collected from a multi-center RCT were used as the examples and processed by CMH test and meta-analysis. Results The result of CMH test indicated that the significant difference of the effect values existed among centers （P 〈0. 05 ）. While meta-analysis showed no significant difference （P 〉0.05 ） by heterogeneity test. However, when using fixed effect model, inter-group significant difference of merged effect values was observed （P 〈0.05 ）. Conclusions In the clinical research based on the method of multi-center RCT, met.a-analysis can be applied if the difference of inclination of the inter-group therapeutic effect is found among different centers. The proper mathematical model should be selected based on the result of heterogeneity test to merge and compare the effect values. The conclusions should be drawn from the results of both meta-analysis and CMH test.
Objective To review systematically whether there is enough existing evidence that methylcobalamin is effective and safe in the treatment of the patients with diabetic peripheral neuropathy.Methods A Cochrane systematic review of all relevant randomized or quasi-randomized controlled trials of methycobalamin for diabetic peripheral neuropathy was performed. Clinical trials were searched from Cochrane Controlled Trials Register (Issue 4, 2003), MEDLINE (January 1966 to January 2004), EMBASE (January 1980 to January 2004), the Chinese Biological Medicine Database (1978 to January 2004), the Chinese Science and Technology Journal Full-text Database (1989 to January 2004) and references of all included trials. The selection of studies, data extraction and assessment of methodological quality were performed independently by two reviewers. The following outcomes were assessed: effectiveness of clinical signs and symptoms, sensory nerve and motor nerve conduction velocities and serious adverse events of methylcobalamin. Results Thirty randomized clinical trials including 1 949 patients met the inclusion criteria. The quality of the most included trials was of low level. The "funnel plot" of the comparison of thirteen studies of methylcobalamin with other B Vitamins studies showed symmetry, which indicated less possible publication bias and the result was partly reliable, but it could not indicate the whole publication biases. The results of meta-analysis indicated that methylcobalamin showed significantly positive effects on the improvement of the signs and symptoms of peripheral neuropathy, and the effects were better than the other vitamin B agents. The increase of some nerves conduction velocities by methylcobalamin was better than by the other vitamin B. No serious adverse events were observed during the treatment period.Conclusions Methylcobalamin appears to be a safe and effective treatment on diabetic peripheral neuropathy. However, the evidence is not b because of the low quality of most trials. Rigorously designed, randomized, double-blinded, placebo-controlled trials of methylcobalamin for diabetic peripheral neuropathy are needed to further assess the effect.
Randomized controlled trials (RCTs) are the gold standard for the design of clinical trials. Because of some practical difficulties, more and more researchers think that the appropriate use of non-randomized controlled trials may make up for the weakness of RCT and will achieve the same research purpose. Therefore, non-RCTs are also very important. Taking studies on multiple sclerosis for example, this article briefly introduces the significance of non-randomized contolled trials.
Objective To review the eradication rate for Helicobacter Pylori (H. pylori) eradication therapy with Ranitidine bismuth citrate (RBC). Methods A systematic review of all the relevant randomized controlled trials (RCTs) was performed according to International Cochrane Collaboration. Data Source RCTs were identified from specialized trials register of Cochrane U GDP Group, the Cochrane library, additional electronic search (including MEDLINE and CBM), handsearching, and personal contact with pharmaceutical companies. Data Selection Randomized clinical trials comparing RBC or RBC in combination with other antibiotics such as proton pump inhibitor, H2-receptor antagonist, other bismuth or placebo were included. No language and blinding limitations were applied. Inclusion criteria Data were extracted independently by two reviewers. The methodological quality of trials was assessed by the Jadad-scale plus allocation concealment. Statistics analysis was managed by using RevMan 4. 1. Results Fifteen randomized clinical trials including 3 638 patients were included, with eight trials of high methodological quality. Meta-analysis indicated that odds ratio was 3.06 (95%CI 2.62 to 3. 58, P lt; 0. 000 01) comparing RBC to controls. But the heterogeneity was significant (P lt; 0. 000 01), so we choose random effects model. Then the odds ratio was 2.05 (95%CI 1. 29 to 3. 25, P=0.002). No serious adverse effects were found. Sensitivity analysis showed that the specimens and the quality of RCT haven’t affected researching result. Conclusion RBC is more effective in Helicobacter Pylori eradication therapy than others.