Randomised controlled trials meta-analysis

Bath P, Iddenden R, Bath F. Low-molecular-weight heparins and heparinoids in acute ischemic stroke, a meta-analysis of randomised controlled trials. Stroke 2000 31 1770-1778. 

Costa J, Borges M, David C, Vaz Carneiro A. Efficacy of lipid lowering dmg treatment for diabetic and nondiabetic patients meta-analysis of randomised controlled trials. BMJ 2006 332 1115-24. 

Ashcroft DM, Dimmock P, Garside R, Stein K, Williams HC. Efficacy and tolerability of topical pimecrolimns and tacrolimus in the treatment of atopic dermatitis meta-analysis of randomised controlled trials. BMJ 2005 330 516-21. 

Wilkes MM, Navickis RJ. Patient survival after human albumin administration a meta-analysis of randomised controlled trials. Ann Intern Med 2001 135 149-64. 

Linde et al St. John s wort for depression—meta-analysis of randomised controlled trials. Br J Psychiatry 2005 186 99. [PMID 15684231]... 

Zhang W, Jones A, Doherty M. Does paracetamol (acetaminophen) reduce the pain of osteoarthritis A meta-analysis of randomised controlled trials. Ann Rheum Dis. 2004 63 901-907. 

Bech, R, Cialdella, P., Haugh, M. C., Birkett, M. A., Hours, A., Boissel, J. P., Tollefson, G. D. 2000, Meta-analysis of randomised controlled trials of fluoxetine v. placebo and tricyclic antidepressants in the short-term treatment of major depression, Br.J.Psychiatry, vol. 176, pp. 421 28. 

Gunnell, D., Saperia, J., Ashby, D. 2005, Selective serotonin reuptake inhibitors (SSRIs) and suicide in adults meta-analysis of dmg company data from placebo controlled, randomised controlled trials submitted to the MHRA s safety review, Br.Med.f, vol. 330, no. 7488, p. 385. 

Leucht S, Barnes TRE, Kissling W, Engel RR, Correll C, Kane JM. Relapse prevention in schizophrenia with new-generation antipsychotics a systematic review and exploratory meta-analysis of randomised, controlled trials. Am J Psychiatry 2003 160 1209-22. 

Grade A, meta-analysis of randomised, controlled trials or from at least one randomised, controlled trial, or from at least one well designed, controlled study without randomisation grade B, from at least one other type of well designed, quasi-experlmental study, or from well designed, nonexperimental studies (e.g. comparative studies, correlation studies, case-control studies) grade C, from expert committee reports/opinions and/or clinical experience of authorities, ND, not demonstrated. Data from the Royal College of Physicians and the Bone and Tooth Society. 

Etminan M, Samii A, Takkouche B, Rochon PA. Increased risk of somnolence with the new dopamine agonists in patients with Parkinson s disease a meta-analysis of randomised controlled trials. Drug Saf 2001 24(ll) 863-8. 

Gueyffier F, Bulpitt C, Boissel JP, et al. Antihypertensive drugs in very old people A subgroup meta-analysis of randomised controlled trials. INDANA Group. Lancet 1999 353 793-796. 

Pickup J, Mattock M, Kerry S. Glycaemic control with continuous subcutaneous insulin infusion compared with intensive insulin injections in patients with type 1 diabetes Meta-analysis of randomised controlled trials. BMJ 2002 324 705. 

While phytochemical and pharmacological information is helpful, the true test of the medicinal value of a plant lies in its demonstrated clinical usefulness. The difficulties involved in submitting plants and plant extracts to rigorous clinical scrutiny in the absence of patent protection have been well documented. Equally the fact that a number of important plants have been subjected to randomised controlled trials has been documented. While some trials can be criticised in the same way that trials of synthetic drugs can be criticised, the table below shows the types of plants which have been clinically evaluated and found to be superior to placebo. For some plants there is even meta-analysis data available. 

Bucher HC, Hengstler P, Schindler C, Guyatt GH. Percutaneous transluminal coronary angioplasty versus medical treatment for non-acute coronary heart disease meta-analysis of randomised controlled trials. BMJ 2000 Jul 8 321(7253) 73-7. 

Juni et al. (2004) carried out a cumulative meta-analysis in which they included all randomised controlled trials in patients with chronic musculoskeletal disorders that compared rofecoxib with other non-steroidal anti-inflammatory drugs (NSAIDs) or placebo (p. 2021). The outcomes targeted were cardiovascular side-effects, in particular myocardial infarctions, and they found that by the year 2000 there was already evidence of a significant effect on rofecoxib on cardiovascular health, which they interpreted as harm compared with placebo. This drew an angry response from Kim and Reicin (2004), who worked for Merck, the makers of rofecoxib, claiming that the approach contravenes the basic principle of meta-analyses to combine like with like, and thus arrives at flawed conclusions . 

Roiron C, Sanchez P, Bouzamondo A et al. Drug eluting stents An updated meta-analysis of randomised controlled trials. Heart 2006 92 641-649. 

Dias, S., N.J. Welton, A.J. Sutton et al. 2011a. NICE DSU technical support document 2 A generalised linear modelling framework for pairwise and network meta-analysis of randomised controlled trials. Last updated April 2012 available from http //www.nicedsu.org.uk. 

A meta-analysis brings together data from different studies in a quantitative way so as to provide a single overall estimate of a specified effect. When doing this, it is best to use only evidence of one particular type (e.g. from randomised trials) and the outcome(s) must be expressed in the same terms for all the studies. Whilst meta-analysis has also been most often focused on efficacy, it can be used for adverse outcomes and the method is increasingly contributing to drug safety issues. Meta-analysis of data from observational studies is possible but more controversial than for randomised controlled trials. 

Beibei L, Yun C, Mengli C, Nan B, Xuhong Y, Rui W. Linezolid versus vancomycin for the treatment of grampositive bacterial infections meta-analysis of randomised controlled trials. Lit J Antimicrob Agents 2010 35(1) 3-12. 

Mei, W., Rong, Y., Jimning, L., Yongjun, L., and Hui, Z., 2010. Effect of homocysteine interventions on the risk of cardiocerebrovascular events a meta-analysis of randomised controlled trials. International Journal of Clinical Practice. 64 208-215. 

The serious adverse effects of salmeterol when added to ICS, in asthmatic adults and children, were assessed by another Cochrane meta-analysis [36 ]. The meta-analysis included 40 randomised controlled trials studies, with a total population of 15,309 participants and was foxmd to have a low risk of bias. Salmeterol with ICS was not associated with mortality (adults Peto OR = 0.90, 95% Cl = 0.31, 2.60, children no reported deaths). Furthermore, there was no significant association between salmeterol with ICS and the risk of serious adverse effects, in adults (Peto OR = 1.15,95% Cl = 0.91,1.44), or in children (Peto OR = 1.20,95% Cl = 0.37,3.91). No between-group difference was found in asthma-related serious adverse effects in those receiving salmeterol with ICS compared to ICS only (adults Peto OR = 1.12,95% Cl = 0.65,1.94. Children only one asthma related event in each group). 

A meta-analysis comparing telithromycin with clarithromycin reviewed data from five randomised controlled trials. Adverse events were similar in both groups. Common adverse events included diarrhoea, nausea, vomiting, flatulence, dyspepsia and abdominal pain. Other events included headache, oral candidiasis, dizziness, dysgeusia, abnormal liver function tests and fatigue. Serious adverse events included allergic reactions, abnormal liver function tests as well as death (in three cases) [86 ]. 

Comparative studies A meta-analysis was performed comparing early antiviral efficacy and safety of telbivudine and entecavir in the treatment of patients with hepatitis B e antigen positive chronic hepatitis [106 ]. Six randomised controlled trials involving 555 patients were included and demonstrated that telbivudine was associated with higher rates of HBeAg disappearance and HBeAg seroconversion than entecavir but had higher adverse events (RR 2.11). No specific details of adverse events were illustrated as pooled risk ratios were used. 

Cardiovascular An FDA led meta-analysis of 26 randomised controlled trials (n=9868) found no association between ABC use and the risk of a myocardial infarction [142 ]. 

The efficacy and safety of 1-omithine-L-aspartate for treatment of hepatic encephalopathy in patients with cirrhosis has been evaluated in a meta-analysis of eight randomised controlled trials including a total of 646 patients. There were no significant differences in the frequency of adverse events between the intervention and control groups, and no serious adverse events were reported [100 ]. 

Messori A, Tripoli S, Vaiani M, et al. Bleeding and pneumonia in intensive care patients given ranitidine and sucralfate for jnevention of stress ulcer meta-analysis of randomised controlled trials. BMJ 2003 32 1103-1106. 

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