Systematic review of trials

In a systematic review of trials of piracetam in Alzheimer s disease the evidence of effects on cognition and other measures was inconclusive (10). The reviewers concluded that the evidence available from the published literature does not support the use of piracetam in the treatment of people with dementia or cognitive impairment. 

Randomized trials and systematic reviews of trials, therefore, provide the most reliable data on the effects of treatment. That is not to say, however, that non-randomized studies cannot sometimes provide reliable evidence on the benefits of intervention. Few people would doubt the validity of the observational data on the benefits of antibiotic treatment in bacterial meningitis or the benefits of treatment with levodopa in Parkinson s disease. Similarly, clinical guidelines have been revised worldwide on the basis of the non-randomized evidence of the substantial reduction in the risk of early recurrent stroke (see Fig. 19.2, p. 245) as a result of the urgent initiation of standard secondary prevention (Rothwell et al. 2007). 

Kawamoto, K., Houlihan, C.A., Balas, B.A. and Lobach, D.F. (2005) Improving clinical practice using clinical decision support systems a systematic review of trials to identify features critical to success. British Medical Journal, 330(7494), 765. 

C. E. Lawrance, A. M. Croft. Do mosquito coils prevent malaria A systematic review of trials. J Travel Med, 11, 92, 2004. 

Gijsman HJ, Geddes JR, Rendell JM, et al. Antidepressants for bipolar depression a systematic review of randomized, controlled trials. Am J Psychiatry 2004 161 1537-1547. 

Cochrane Library. The Cochrane Library [44] includes The Cochrane Database of Systematic Reviews, a collection of regularly updated, systematic reviews of the effects of health care. It is maintained by contributors to the Cochrane Collaboration. Cochrane reviews are reviews mainly of randomized controlled trials. To minimize bias, evidence is included or excluded on the basis of explicit quality criteria. Data are often combined statistically, with meta-analysis, to increase the power of the findings of numerous studies, each too small to produce reliable results individually. Database of Abstracts of Reviews of Effectiveness is also included. It consists of critical assessments and structured abstracts of good systematic reviews published elsewhere. The Cochrane Controlled Trials Register with bibliographic information on controlled trials and other sources of information on the science of reviewing research and evidence-based health care are part of the Cochrane Library. It is commercially available on CD-ROM or the Internet. 

Fergusson, Dean, Steve Doucette, Kathleen Cranley Glass, Stan Shapiro, David Healy, Hebert Paul and Brian Hutton, Association between Suicide Attempts and Selective Serotonin Reuptake Inhibitors Systematic Review of Randomised Controlled Trials , British Medical Journal 330 (2005) 396-99... 

Hotopf, M., G. Lewis and C. Normand, Putting Trials on Trial - the Costs and Consequences of Small Trials in Depression A Systematic Review of Methodology Journal of Epidemiology and Community Health 51 (1997) 354-58... 

Als-Nielsen B, Gluud LL, Gluud C Nonabsorbable disaccharides for hepatic encephalopathy Systematic review of randomised trials. BMJ 2004 328 1046-1050. 

Song F, Glenny AM Antimicrobial prophylaxis in colorectal surgery A systematic review of randomized controlled trials. Br J Surg 1998 ... 

Within the last 20 years or so, three major features of controlled clinical trials, in particular, have permitted significant advances in deciding whether treatments are of value or not randomisation, systematic review and metaanalysis, and the concept of the large-scale, simple (to understand and conduct) randomised trial in areas where only moderate benefits can be expected.All of these elements are likely to underpin future trials for purposes of regulation, pharmacoeconomics and healthcare policy. Yet there is no room for complacency or allowing standards to slip. Systematic reviews of some... 

Ezekowitz JA, Armstrong PW, McAlister FA. Implantable cardioverter defibrillators in primary and secondary prevention a systematic review of randomized, controlled trials. Ann Intern Med. Mar 18 2003 138(6) 445-452. 

Whitten DL, Myers SP, Hawrelak JA, Wohlmuth H. The effect of St John s wort extracts on CYP3A a systematic review of prospective clinical trials. Br J Clin Pharmacol 2006 62 512-26. 

Kaduszkiewicz H, Zimmermann T, Beck-Bornholdt H, van den Bussche H. Cholinesterase inhibitors for patients with Alzheimer s disease systematic review of randomised clinical trials. BMJ 2005 331(7512) 321-7. 

Canter PH, Wider B, Ernst E. The antioxidant vitamins A, C, E and selenium in the treatment of arthritis a systematic review of randomized clinical trials. Rheumatology (Oxford) 2007 46(8) 1223-33. 

A systematic review of six trials involving a total of 55 people concludes that caffeine appears to improve airways function modestly in people with asthma for up to four hours. People may need to avoid caffeine for at least four hours prior to lung function testing. 

From a systematic review of six trials involving 321 infants in three different settings which at the time of writing was present in the Cochrane data... 

Finally, a systematic review of ten trials including 2036 patients dealing with the prevention of seizures after brain injury concludes Prophylactic anti-epileptics are effective in reducing early seizures, but there is no evidence that treatment with prophylactic anti-epileptics reduces the occurrence of late seizures, or has any effect on death and neurological disability. Insufficient evidence is available to establish the net benefit of prophylactic treatment at any time after injury . 

Sarcomas are tumors of mesenchymal origin, arising in skeletal tissues and extra-skeletal connective tissues including the nerves. They are very rare and mainly effect a younger population. Sarcomas of soft tissues are relatively insensitive to drug treatment and are therefore not discussed in detail in this chapter. A systematic review of fourteen trials of doxorubicin-based adjuvant chemotherapy for the treatment of soft tissue sarcomas involving 1568 patients concluded Doxorubicin-based adjuvant chemotherapy appears to significantly improve time to local and distant recurrence and overall recurrence-free survival in adults with localised resectable soft tissue sarcoma. There is some evidence of a trend towards improved overall survival (see Sarcoma Meta-analysis Collaboration, 1999). 

Thunainen A, Wahlbeck K, and Gilbody S. Newer atypical antipsychotic medication in comparison to clozapine A systematic review of randomized trials. Schizophr Res 2002 56 1-10. 

ZO072 Ernst, E., and M. H. Pittler. Efficacy of ginger for nausea and vomiting a systematic review of randomized clinical trials. Br J Anaesth 2000 84(3) 367-371. 

Ernst E, Pittler MH. Ginkgo biloba for dementia a systematic review of doubleblind placebo-controlled trials. Clin Drug Invest 199 17 301-308. 

Canter PH, Ernst E. Ginkgo biloba. a smart drug A systematic review of controlled trials of the cognitive effects of Ginkgo biloba extracts in healthy-people. Psychopharmacol Bull 2002 36 108-123. 

Vogler BK, Pittler MH, Ernst E. The efficacy of ginseng. A systematic review of randomised clinical trials. Eur J Clin Pharmacol 1999 55 567-575. 

Cochrane Injuries Group Albumin Review. Human albumin administration in critically ill patients Systematic review of randomised controlled trials. BMJ 1998 317 235-40. de Jonge E, Levi M, Berends F, et al. Impaired haemostasis by intravenous administration of a gelatin-based plasma expander in human subjects. Thromb Haemost 1998 79 286-90. 

Deeks JJ, Smith LA, Bradley MD Efficacy, tolerability, and upper gastrointestinal safety of celecoxib for treatment of osteoarthritis and rheumatoid arthritis Systematic review of randomised controlled trials. BMJ 2002 325 619. [PMID 12242171]... 

Arrieta, J.L., Artalejo, F.R. (1998). Methodology, results and quality of clinical trials of tacrine in the treatment of Alzheimer s disease a systematic review of the literature. Age Ageing, 27, 161-79. 

A systematic review of randomized controlled trials has been performed to determine whether dexamethasone therapy in the first 15 days of life prevents chronic lung disease in premature infants (14). Studies were identified by a literature search using Medline (1970-97) supplemented by a search of the Cochrane Library (1998, Issue 4). Inclusion criteria were (a) prospective randomized design with initiation of dexamethasone therapy within the first 15 days of life (b) report of the outcome of interest and (c) less than 20% crossover between the treatment and control groups during the study period. The primary outcomes were mortality at hospital discharge and the development of chronic lung disease at 28 days of life and 36 weeks postconceptional age. The secondary outcomes were the presence of a patent ductus... 

A systematic review of the use of misoprostol for induction of labor has been published (16). The meta-analysis included all randomized clinical trials registered in the Cochrane Pregnancy and Childbirth Group. Vaginal misoprostol was associated with increased uterine hyperstimulation, both without fetal heart changes (RR = 1.67 Cl = 1.30, 2.14) and with associated fetal heart rate changes (RR = 1.45 Cl = 1.04, 2.04). There was also an increase in meconium-stained amniotic fluid (RR = 1.38 Cl = 1.06,1.79). 

Edwards JE, Moore RA. Finasteride in the treatment of clinical benign prostatic hyperplasia a systematic review of randomised trials. BMC Urol 2002 2 14. 

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