Showing papers by "Cochrane Collaboration published in 1998"
TL;DR: Despite some evidence of effectiveness of specific regimens, the relevance of these findings is limited by the modest survival benefit and the lack of evaluation of the quality-of-life impact of these treatments.
Abstract: PURPOSEA systematic review of randomized clinical trials (RCTs) was undertaken to assess the effectiveness of medical treatment for metastatic breast cancer.METHODSRCTs published between 1975 and 1997 have been classified according to 12 therapeutic comparisons: (1) polychemotherapy (PCHT) agents versus single agent; (2) PCHT regimens with anthracycline versus PCHT without anthracycline; (3) other PCHT versus cyclophosphamide, methotrexate, and fluorouracil (CMF); (4) chemotherapy (CHT) with epirubicin versus CHT with doxorubicin; (5) CHT versus same CHT delivered with less intensive schedules; (6) other endocrine therapy (OET) versus tamoxifen; (7) OET plus tamoxifen versus tamoxifen alone; (8) OET versus medroxyprogesterone; (9) OET versus aromatase inhibitors; (10) OET versus megestrol; (11) endocrine therapy (ET) versus same ET at lower doses; and (12) CHT plus ET versus CHT. Tumor response rates, mortality hazards ratio (HR) and frequency of severe side effects were the outcome measures.RESULTSA tota...
511 citations
TL;DR: The drug regulatory authorities should stipulate that the results of both explanatory and pragmatic trials are necessary before a compound is given a licence for everyday use, and much scope for well planned, conducted, and reported trials is left.
Abstract: Objective To provide a comprehensive survey of the content and quality of intervention studies relevant to the treatment of schizophrenia. Design Data were extracted from 2000 trials on the Cochrane Schizophrenia Group9s register. Main outcome measures Type and date of publication, country of origin, language, size of study, treatment setting, participant group, interventions, outcomes, and quality of study. Results Hospital based drug trials undertaken in the United States were dominant in the sample (54%). Generally, studies were short (54% Conclusions Half a century of studies of limited quality, duration, and clinical utility leave much scope for well planned, conducted, and reported trials. The drug regulatory authorities should stipulate that the results of both explanatory and pragmatic trials are necessary before a compound is given a licence for everyday use.
343 citations
TL;DR: Current chemical and physical methods aimed at reducing exposure to allergens from house dust mites seem to be ineffective and cannot be recommended as prophylactic treatment for asthma patients sensitive to mites.
Abstract: Objective To determine whether patients with asthma who are sensitive to mites benefit from measures designed to reduce their exposure to house dust mite antigen in the home.
Design Meta-analysis of randomised trials that investigated the effects on asthma patients of chemical or physical measures to control mites, or both, in comparison with an untreated control group. All trials in any language were eligible for inclusion.
Subjects Patients with bronchial asthma as diagnosed by a doctor and sensitisation to mites as determined by skin prick testing, bronchial provocation testing, or serum assays for specific IgE antibodies.
Main outcome measures Number of patients whose allergic symptoms improved, improvement in asthma symptoms, improvement in peak expiratory flow rate. Outcomes measured on different scales were combined using the standardised effect size method (the difference in effect was divided by the standard deviation of the measurements).
Results 23 studies were included in the meta-analysis; 6 studies used chemical methods to reduce exposure to mites, 13 used physical methods, and 4 used a combination. Altogether, 41/113 patients exposed to treatment interventions improved compared with 38/117 in the control groups (odds ratio 1.20, 95% confidence interval 0.66 to 2.18). The standardised mean difference for improvement in asthma symptoms was −0.06 (95% confidence interval −0.54 to 0.41). For peak flow rate measured in the morning the standardised mean difference was −0.03 (−0.25 to 0.19). As measured in the original units this difference between the treatment and the control group corresponds to −3 l/min (95% confidence interval −25 l/min to 19 l/min). The results were similar in the subgroups of trials that reported successful reduction in exposure to mites or had long follow up times.
Conclusion Current chemical and physical methods aimed at reducing exposure to allergens from house dust mites seem to be ineffective and cannot be recommended as prophylactic treatment for asthma patients sensitive to mites.
215 citations
TL;DR: In this paper, the authors designed search strategies based on a more objective approach to strategy construction, which were mostly devised for the MEDLINE database, have been constructed using the authors' knowledge of the subject area, the databases and past experience.
Abstract: Background: systematic reviews are of increasing importance to health care professionals seeking to provide evidence-based health care, because they provide systematically prepared summaries of the current state of research knowledge on the effectiveness of health care interventions. To be able to make use of them, both researchers preparing systematic reviews and health care professionals need to be able to identify systematic reviews easily. In the past, systematic reviews have been difficult to identify easily among the mass of literature labelled ‘reviews’. Search strategies have been published which were intended to provide easier access to systematic reviews and meta-analyses. These strategies, mostly devised for the MEDLINE database, have been constructed using the authors’ knowledge of the subject area, the databases and past experience.Objective: the objective of this study was to design search strategies based on a more objective approach to strategy construction.Methods: word frequencies from t...
99 citations
TL;DR: Prednisolone in low doses—that is, no more than 15 mg daily—is highly effective in patients with rheumatoid arthritis The risk of adverse effects is acceptable in short, moderate, or long term use Oral low dose prednisolones may be used intermittently in Patients with r heumatoidthritis, particularly if the disease cannot be controlled by other means.
Abstract: Objective: To determine whether short term, oral low dose prednisolone (⩽15 mg daily) is superior to placebo and non-steroidal anti-inflammatory drugs in patients with rheumatoid arthritis. Design: Meta-analysis of randomised trials of oral corticosteroids compared with placebo or a non-steroidal anti-inflammatory drug. Setting: Trials conducted anywhere in the world. Subjects: Patients with rheumatoid arthritis. Main outcome measures: Joint tenderness, pain, and grip strength. Outcomes measured on different scales were combined by using the standardised effect size (difference in effect divided by SD of the measurements). Results: Ten studies were included in the meta-analysis. Prednisolone had a marked effect over placebo on joint tenderness (standardised effect size 1.31; 95% confidence interval 0.78 to 1.83), pain (1.75; 0.87 to 2.64), and grip strength (0.41; 0.13 to 0.69). Measured in the original units the differences were 12 (6 to 18) tender joints and 22 mm Hg (5 mm Hg to 40 mm Hg) for grip strength. Prednisolone also had a greater effect than non-steroidal anti-inflammatory drugs on joint tenderness (0.63; 0.11 to 1.16) and pain (1.25; 0.26 to 2.24), whereas the difference in grip strength was not significant (0.31; −0.02 to 0.64). Measured in the original units the differences were 9 (5 to 12) tender joints and 12 mm Hg (−6 mm Hg to 31 mm Hg). The risk of adverse effects during moderate and long term use seemed acceptable. Conclusion: Prednisolone in low doses (⩽15 mg daily) may be used intermittently in patients with rheumatoid arthritis, particularly if the disease cannot be controlled by other means. Key messages Prednisolone in low doses—that is, no more than 15 mg daily—is highly effective in patients with rheumatoid arthritis The risk of adverse effects is acceptable in short, moderate, or long term use Oral low dose prednisolone may be used intermittently in patients with rheumatoid arthritis, particularly if the disease cannot be controlled by other means Further short term placebo controlled trials to study the clinical effect of prednisolone or other oral corticosteroids are no longer necessary
96 citations
TL;DR: The philosophies and rationales behind this trend in consumer involvement in health care internationally are addressed and the history and development of consumer advocacy in health Care is traced.
Abstract: Forces from communities and from health care are pushing toward more consumer involvement in health care internationally. This article addresses the philosophies and rationales behind this trend and traces the history and development of consumer advocacy in health care.
82 citations
TL;DR: It is proved that the recovered derivative by the least-squares fitting is superconvergent for the two-point boundary value problems and the a posteriori error estimator based on the recovery technique is shown to be asymptotically exact.
78 citations
TL;DR: Routine calcium supplementation seems to be a promising intervention for pregnant women at risk of developing preeclampsia or have low calcium intake, but these findings need to be confirmed with a trial with adequate power in different settings.
75 citations
63 citations
TL;DR: The British Medical Research Council's trial of streptomycin for pulmonary tuberculosis, published in 1948, has been proposed as the first randomised trial in which random numbers were used and allocation of patients was effectively concealed.
Abstract: The British Medical Research Council's trial of streptomycin for pulmonary tuberculosis, published in 1948,1 has been proposed as the first randomised trial in which random numbers were used and allocation of patients was effectively concealed. Before 1948 several randomised trials had been reported,2 but the method of randomisation was either not stated3 or was open to selection bias—for example, randomisation with use of a deck of cards.4
The earliest of these trials was published in 1898.5 It investigated the effect of serum treatment on diphtheria and was conducted by the Danish Nobel laureate, Johannes Fibiger. It was the first clinical trial in which random allocation was used and emphasised as a pivotal methodological principle. This pioneering improvement in methodology, combined with a large number of patients and rigorous planning, conduct, and reporting, makes the trial a milestone in the history of clinical trials.
Fibiger's trial was published in Danish and its method of randomisation has often been quoted incorrectly. We have translated central passages into English (available on the BMJ website at www.bmj.com) and discussed its methodological merit.
### Summary points
A large randomised clinical trial was performed as early as 1898
Random allocation was emphasised as a central methodological principle
Patients were allocated to serum or no serum according to day of admittance, which created two comparable groups
The planning, conduct, and reporting of the trial was of high quality
The efficacy of serum treatment on diphtheria was shown
The trial was the first properly conducted controlled clinical trial
Johannes A G Fibiger (1867-1928) was born in Silkeborg, Denmark (figure). After receiving his medical degree in 1890 from the University of Copenhagen he visited Robert Koch and Emil von Behring in Germany. In 1895 Fibiger was awarded a doctoral degree for a thesis on diphtheria from the …
62 citations
TL;DR: There is not enough evidence to evaluate the effectiveness of any plague vaccine, or the relative effectiveness between vaccines and their tolerability, and Circumstantial data from observational studies suggest that killed types may be more effective and have fewer adverse effects than attenuated types of vaccine.
Abstract: Background
Plague is endemic in China, Mongolia, Burma, Vietnam, Indonesia, India, large parts of Southern Africa, the United States and South America. There are three types of vaccines (live attenuated, killed and F1 fraction) with varying means of administration.
Objectives
The objective of this review was to assess the effects of vaccines to prevent plague.
Search methods
We searched MEDLINE (1966 to February 2011), EMBASE (1985 to February 2011), CENTRAL (The Cochrane Library 2011, Issue 2) and reference lists of articles. We handsearched the journal 'Vaccine' (up to 1997) and contacted experts in the field.
Selection criteria
Randomized trials comparing live and killed plague vaccines against no intervention, placebo, other plague vaccines or vaccines against other disease (control vaccines).
Data collection and analysis
Three reviewers assessed the eligibility of trials.
Main results
No trials were included.
Authors' conclusions
There is not enough evidence to evaluate the effectiveness of any plague vaccine, or the relative effectiveness between vaccines and their tolerability. Circumstantial data from observational studies suggest that killed types may be more effective and have fewer adverse effects than attenuated types of vaccine. No evidence appears to exist on the long-term effects of any plague vaccine.
TL;DR: Killed anthrax vaccines appear to be effective in reducing the risk of contracting anthrax with a relatively low rate of adverse effects and should be restricted to testing new vaccines only.
Abstract: BACKGROUND Anthrax is an acute bacterial skin disease which may be fatal. Three anthrax vaccines are commercially available but their comparative effectiveness and safety is not clear. OBJECTIVES The objective of this review was to assess the effects of human anthrax vaccines in healthy adults and children. SEARCH STRATEGY We searched the Cochrane Controlled Trials Register, Medline, Embase and the reference lists of articles. We handsearched the journal Vaccine and contacted researchers in the field. SELECTION CRITERIA Randomised and quasi-randomised trials comparing anthrax vaccines with placebo, vaccines for other diseases or no intervention. DATA COLLECTION AND ANALYSIS Trial quality assessment and data extraction was conducted independently by the six authors. MAIN RESULTS Two trials involving 16,052 people were included. Both trials had methodological limitations. Compared to placebo, vaccination was associated with a reduced risk of contracting anthrax (relative risk 0.16, 95% confidence interval 0.07 to 0.35). Compared to placebo, the killed vaccine was associated with a higher incidence and severity of adverse effects (odds ratio 5.15, 95% confidence interval 2.28 to 11.61). Just over 5% of participants in the vaccine group reported adverse effects. The effectiveness of the vaccine does not appear to be influenced by the route of inoculation. REVIEWER'S CONCLUSIONS Killed anthrax vaccines appear to be effective in reducing the risk of contracting anthrax with a relatively low rate of adverse effects. Further research should be restricted to testing new vaccines only.
TL;DR: The basic principles of evidence-based medicine (EBM) link a physician's clinical experience with a systematic appraisal of clinical evidence in medical publications as mentioned in this paper, which is called EBM.
Abstract: The basic principles of evidence-based medicine (EBM) link a physician’s clinical experience with a systematic appraisal of clinical evidence in medical publications. In the words of Ian Mackay: “The report in 1992 by an Evidence-Based Working Group, 1 in which the McMaster originators were well represented, was a major impetus for evidence-based medicine. The report begins: ‘A new paradigm for medical practice is emerging. Evidence-based medicine deemphasizes intuition, unsystematic clinical experience, and pathophysiologic rationale... and stresses the examination of evidence from clinical research.’ The paradigm was seen as lowering the value of ‘authority’ (perhaps the authors meant ‘authoritarianism’), and the ‘final assumption’ was that ‘physicians whose practice is based on an understanding of the underlying evidence will provide superior patient care.’ If a faculty member recommends a therapeutic plan that has been handed down from one generation of physicians to another and the resident assigned to the case questions the basis or effectiveness of that treatment, the resident may wish to perform a computerized bibliographic search, find reliable articles on the subject, discuss them with the faculty member, and proceed to outline an action-plan based on the evidence found.
TL;DR: In this paper, the relationship between the recovery error estimator and the implicit residual estimator was investigated and it was shown that analytically both error estimators are equivalent for one dimensional problems.
Abstract: We present analytical and numerical investigation in the relationship of the recovery error estimator and the implicit residual error estimator It is shown that analytically both error estimators are equivalent for one dimensional problems Numerical study indicates that such equivalence also exist for two dimensional problems
TL;DR: Tamoxifen demonstrates a modest degree of effectiveness in ovarian cancer refractory to cytotoxic chemotherapy, but there is no useful analyzable data on the duration of responses or survival.
Abstract: Williams C. Tamoxifen in related ovarian cancer: A systematic review. Int J Gynecol Cancer 1998; 8: 89–94.
This review examines the evidence for useful clinical activity of tamoxifen in women with ovarian carcinoma who have failed conventional cytotoxic chemotherapy.
The optimized search strategy of the Cochrane Gynaecological Cancer Collaborative Review Group, together with citations provided by Zeneca (the manufacturer of tamoxifen), and authors of trials identified in this area were used. Selection criteria consisted of phase 2 trials, randomized or unrandomized, of tamoxifen in women with ovarian carcinoma, previously treated with cytotoxic chemotherapy. Phase 3 trials in similar patients were also sought. Trials were then assessed for inclusion in the study and data extracted by the author.
There are no randomized controlled trials of tamoxifen alone vs best supportive care in patients with refractory or recurrent ovarian cancer. There is a series of phase 2 trials that report objective response rates and (in some) stable disease rates. Fifty-five of 503 patients (10.9%) were reported to have achieved an objective response and 59 of 291 patients (24%) achieved stable disease (for variable periods). Since only a subset of trials reported rates of stable disease, these may form a biased group favoring a high rate of disease stabilization. There were no analyzable data on duration of response or overall survival. There were no useful data presented on the palliative effects of tamoxifen, in terms of symptom control or quality of life.
Tamoxifen demonstrates a modest degree of effectiveness in ovarian cancer refractory to cytotoxic chemotherapy. The overall objective response rate in all trials (503 patients) was about 11%. There is, however, a wide variation in the objective response rates in the different trials (0% to 56%). This may, in part, reflect varying criteria for selection of patients for inclusion in individual studies and different methods for recording responses and application of these methods. Some trials reported on rates of stabilization of disease, but these data may be biased as such information was only presented in selected studies. There is no useful analyzable data on the duration of responses or survival. There is also, importantly, virtually no data on the palliative effects of tamoxifen given in this situation, even though the intent of treatment was entirely palliative. Those studies that collected data on hormone receptors found no consistent correlation between the presence of receptors and an increased chance of response to tamoxifen.
TL;DR: Recommendations of reviews and open studies for the use of zuclopenthixol acetate in preference to 'standard' treatments in the psychiatric emergency are not supported by evidence from randomized controlled trials.
TL;DR: Qualityassessment is important as vaccines are widely used and decisions about populations must be made on the best available evidence, especially if such practice is regulated bylaw.
Abstract: ).However,todatelittleatten-tion has been paid to summarising andevaluatingitssignificanceintheassessmentofvaccinequality(definedaseYcacy,eVective-ness, eYciency, safety, and acceptability).Qualityassessmentisimportantasvaccinesareawidelyusedpreventivetechnology,vaccina-tionprogrammesaremostlypubliclyfunded,anddecisionstoimmunisewholepopulationsmustbemadeonthebestavailableevidence,especiallyifsuchpracticeisregulatedbylaw.Additionally the current array of vaccines islikelytobeaugmentedconsiderablyinscopeand variety by new vaccines imposing aresourceburdenonsociety.Suchaburden,setagainstthebackdropofincreasedhealthcarecosts,willnecessitatediscriminationoffundingof preventive programmes. DiscriminationshouldbepartlybasedonthebestavailableevidenceofvaccineeVectivenessandsafety,ofthesocialburdenofthetargetdiseaseandoftheabilityofthevaccinetopreventthatburdendeveloping.
Journal Article•
TL;DR: It is concluded that the expected day of delivery should be calculated by adding 283 days to the date of the last period rather than by adding 280 days, because for women with regular cycles and known first day of theLast menstrual period, ultrasound dating does not lead to a more precise prediction.
Abstract: It has been claimed that the expected day of delivery (EDD) determined on the basis of an ultrasound scan is more accurate than using a calendar method. The aim of this paper is to assess the evidence in support of this claim. A critical review of the methodologically best research revealed that among women with regular cycles and know first day of the last menstrual period, Naegele's rule predicted the EDD to be 3.3 days too early, on average, whereas prediction based on ultrasound scans was 2.0 days too late. The standard deviations of the two distributions were the same. After correction for the systematic biases, the two methods of prediction were thus equally precise. It is concluded that the EDD should be calculated by adding 283 days to the date of the last period rather than by adding 280 days. For women with regular cycles and known first day of the last menstrual period, ultrasound dating does not lead to a more precise prediction.
TL;DR: This brief introduction to the work of the Cochrane Collaboration is an abridged version of the full text appearing in The Cochrane collaboration Brochure available from the following web site: http://som.flinders.edu.au/fusa/cochrane.html
Abstract: This brief introduction to the work of the Cochrane Collaboration is an abridged version of the full text appearing in The Cochrane Collaboration Brochure available from the following web site: http://som.flinders.edu.au/fusa/cochrane.html
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TL;DR: As resentatives of the public interest in the health service, community health councils up and down the country will have welcomed the approach outlined in Making a Difference.
TL;DR: The first issue of Evidence-Based Nursing prompts me to write with a suggestion which I hope you will consider implementing as the journal matures.
Abstract: Felicitations on the birth of Evidence-Based Nursing (EBN) and best wishes for the future. I was particularly glad to see that you have made a start on working out how to select reliable studies reporting qualitative data.
The first issue of EBN prompts me to write with a suggestion which I hope you will consider implementing as the journal matures. I think it is potentially misleading to concentrate on abstracting individual studies (as EBN has begun to) unless either the authors or the …