Janet Martin posted a reference in Lancet by Pogue and Yusuf. Thanks!
In the course of tracking down this reference, I found a couple of other
articles by Pogue and Yusuf that may prove interesting. I have not yet read
these articles, but the abstracts look interesting.
ARTICLE TITLE: Cumulating evidence from randomized trials: utilizing
sequential monitoring boundaries for cumulative meta-analysis.
ARTICLE SOURCE: Control Clin Trials (United States), Dec 1997, 18(6)
p580-93; discussion 661-6
AUTHOR(S): Pogue JM; Yusuf S
AUTHOR'S ADDRESS: Department of Clinical Epidemiology and Biostatistics,
McMaster University, Hamilton, Ontario, Canada.
MAJOR SUBJECT HEADING(S): Meta-Analysis; Randomized Controlled Trials
[statistics & numerical data]
MINOR SUBJECT HEADING(S): Fibrinolytic Agents [therapeutic use]; Magnesium
[therapeutic use]; Methods; Myocardial Infarction [drug therapy]; Stochastic
Processes; Streptokinase [therapeutic use]
INDEXING CHECK TAG(S): Comparative Study; Human
PUBLICATION TYPE: JOURNAL ARTICLE
ABSTRACT: We propose the adaptation of classical monitoring boundaries for
use in cumulative meta-analysis as guidelines for deciding when accumulating
evidence is statistically significant and medically convincing. The
interpretation of information from a randomized controlled trial is compared
with that from a meta-analysis. The concept of optimal information size for
a meta-analysis is developed and used to adapt monitoring boundaries to
cumulative meta-analysis.
MEDLINE INDEXING DATE: 199803
ISSN: 0197-2456
LANGUAGE: English
UNIQUE NLM IDENTIFIER: 98073018
CAS REGISTRY/EC NUMBER(S): EC 3.4.- (Streptokinase); 0 (Fibrinolytic
Agents); 7439-95-4 (Magnesium)
ARTICLE TITLE: Strengths and limitations of meta-analysis: larger studies
may be more reliable.
ARTICLE SOURCE: Control Clin Trials (United States), Dec 1997, 18(6)
p568-79; discussion 661-6
AUTHOR(S): Flather MD; Farkouh ME; Pogue JM; Yusuf S
AUTHOR'S ADDRESS: Preventive Cardiology and Therapeutics Programme,
Hamilton Civic Hospitals' Research Centre, Ontario, Canada.
MAJOR SUBJECT HEADING(S): Meta-Analysis; Randomized Controlled Trials
MINOR SUBJECT HEADING(S): Bias (Epidemiology); Magnesium [therapeutic use];
Methods; Myocardial Infarction [drug therapy]; Quality Control; Thrombolytic
Therapy
INDEXING CHECK TAG(S): Human
PUBLICATION TYPE: JOURNAL ARTICLE
ABSTRACT: Meta-analysis of randomized controlled trials combines
information from independent studies that address a similar question to
provide more reliable estimates of treatment effects. At the present time,
the methodology and usefulness of meta-analysis is under scrutiny. In the
first part of this paper, we summarize the limitations of meta-analysis and
make suggestions for improvements. In the second part, we illustrate
strengths and limitations using examples of meta-analyses and subsequent
large trials that address the same question. We develop the hypothesis that
the size of the meta-analysis may be a useful measure of reliability. Small
meta-analyses (i.e., those with less than 200 outcome events) may only be
useful for summarizing the available information and generating hypotheses
for future research. The results of small meta-analyses should be regarded
with caution, even if the p value shows extreme statistical significance.
Larger meta-analyses (i.e., those with several hundred events) are likely to
be more reliable and may be clinically useful. Well-conducted meta-analyses
of large trials using individual patient data may provide the best estimates
of treatment effects in the cohort overall and in clinically important
subgroups.
MEDLINE INDEXING DATE: 199803
ISSN: 0197-2456
LANGUAGE: English
UNIQUE NLM IDENTIFIER: 98073017
CAS REGISTRY/EC NUMBER(S): 7439-95-4 (Magnesium)
Steve Simon, [log in to unmask], Standard Disclaimer.
STATS: STeve's Attempt to Teach Statistics.
http://www.cmh.edu/stats [Web site is temporarily down]
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