Statistically significant meta-analyses of clinical trials have modest credibility and inflated effects
Φόρτωση...
Ημερομηνία
Συγγραφείς
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer-reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
J Clin Epidemiol
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
OBJECTIVE: To assess whether nominally statistically significant effects in meta-analyses of clinical trials are true and whether their magnitude is inflated. STUDY DESIGN AND SETTING: Data from the Cochrane Database of Systematic Reviews 2005 (issue 4) and 2010 (issue 1) were used. We considered meta-analyses with binary outcomes and four or more trials in 2005 with P<0.05 for the random-effects odds ratio (OR). We examined whether any of these meta-analyses had updated counterparts in 2010. We estimated the credibility (true-positive probability) under different prior assumptions and inflation in OR estimates in 2005. RESULTS: Four hundred sixty-one meta-analyses in 2005 were eligible, and 80 had additional trials included by 2010. The effect sizes (ORs) were smaller in the updating data (2005-2010) than in the respective meta-analyses in 2005 (median 0.85-fold, interquartile range [IQR]: 0.66-1.06), even more prominently for meta-analyses with less than 300 events in 2005 (median 0.67-fold, IQR: 0.54-0.96). Mean credibility of the 461 meta-analyses in 2005 was 63-84% depending on the assumptions made. Credibility estimates changed >20% in 19-31 (24-39%) of the 80 updated meta-analyses. CONCLUSIONS: Most meta-analyses with nominally significant results pertain to truly nonnull effects, but exceptions are not uncommon. The magnitude of observed effects, especially in meta-analyses with limited evidence, is often inflated.
Περιγραφή
Λέξεις-κλειδιά
Bias (Epidemiology), Clinical Trials as Topic/*standards, Health Services Research/methods/standards, Humans, *Meta-Analysis as Topic
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
http://www.ncbi.nlm.nih.gov/pubmed/21454050
http://ac.els-cdn.com/S0895435611000096/1-s2.0-S0895435611000096-main.pdf?_tid=850ed0e83aa218ff99419c07f5ba70ba&acdnat=1333363381_46c982d4ce43cdc44491c0772f59f1d7
http://ac.els-cdn.com/S0895435611000096/1-s2.0-S0895435611000096-main.pdf?_tid=850ed0e83aa218ff99419c07f5ba70ba&acdnat=1333363381_46c982d4ce43cdc44491c0772f59f1d7
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Επιστημών Υγείας. Τμήμα Ιατρικής