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Weaknesses of major randomized trials: they are cleverly designed against coronary surgery. They are not representative of the daily practice (highly selected patient population), but their results are generalized for the whole population with CAD.
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Weaknesses of major randomized trials: they are cleverly designed against coronary surgery. They are not representative of the daily practice (highly selected patient population), but their results are generalized for the whole population with CAD.
RANDOMIZATION IN ARTSTRIAL(Arterial Revascularization Therapy Study) University Hospital Zürich, April-December 1997 5/986 (0.5 %) patients
STUDY ENROLLMENT IN MAJOR RANDOMIZED STUDIES COMPARING PTCA TO CABG (91 730 patients)RITA, ERACI, GABI, EAST, CABRI AND BARI trials
It is a well-known fact that patients recruited for trial have better survival and better results than those eliminated from the trial because of some exclusion criteria.
NIFEDIPINE IN ACUTE MYOCARDIAL INFARCTION (TRENT TRIAL)(9292 patients admitted with AMI)
When analyzing a trial, look carefully at “Material and Methods” section: crucial information explaining the results might be found there.
Enrollment and Randomization of Patients with Previously Untreated Three-Vessel or Left Main Coronary Artery Disease in the SYNTAX Trial 2 years, 85 centres:10.6 patients/year Serruys P et al. N Engl J Med 2009;360:961-972
Average number of patients seen by centres in Syntax trial is less than 11 patients/year! If we accept the fact that “all comers” entered the trial, these centres should have been closed long ago, according to present standard of PCI and CABG practice.
Cardiac-Related Medications Given after the Study Procedure Serruys P et al. N Engl J Med 2009;360:961-972
A study with a radically different drug treatment protocols in the two analyzed groups is statistically invalid.
Difference in outcome in trials funded by for-profit and not-for-profit sourcesJAMA 2006; 295(19):2270-4
Beware of industry sponsored trials! Results very often meet the sponsor’s expectations!
CABG MORTALITY RATES AMONG DIFFERENT SURGEONS: A PROSPECTIVE STUDYJAMA 1991;266:803-809
There is a major difference between swallowing a pill and performing a complex operation; this fact is not appreciated by statisticians.
Survival with CABG @ 3 years is 28.4 % higher! Hannan E et al. N Engl J Med 2005;352:2174-2183
Non-randomized observational trials can reach very important results, which are presently ignored by the academia schooled in conventional statistics