Excess significance bias in the literature on brain volume abnormalities
Φόρτωση...
Ημερομηνία
Συγγραφείς
Ioannidis, J. P.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer-reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Arch Gen Psychiatry
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
CONTEXT: Many studies report volume abnormalities in diverse brain structures in patients with various mental health conditions. OBJECTIVE: To evaluate whether there is evidence for an excess number of statistically significant results in studies of brain volume abnormalities that suggest the presence of bias in the literature. DATA SOURCES: PubMed (articles published from January 2006 to December 2009). STUDY SELECTION: Recent meta-analyses of brain volume abnormalities in participants with various mental health conditions vs control participants with 6 or more data sets included, excluding voxel-based morphometry. DATA EXTRACTION: Standardized effect sizes were extracted in each data set, and it was noted whether the results were "positive" (P < .05) or not. For each data set in each meta-analysis, I estimated the power to detect at alpha = .05 an effect equal to the summary effect of the respective meta-analysis. The sum of the power estimates gives the number of expected positive data sets. The expected number of positive data sets can then be compared against the observed number. DATA SYNTHESIS: From 8 articles, 41 meta-analyses with 461 data sets were evaluated (median, 10 data sets per meta-analysis) pertaining to 7 conditions. Twenty-one of the 41 meta-analyses had found statistically significant associations, and 142 of 461 (31%) data sets had positive results. Even if the summary effect sizes of the meta-analyses were unbiased, the expected number of positive results would have been only 78.5 compared with the observed number of 142 (P < .001). CONCLUSION: There are too many studies with statistically significant results in the literature on brain volume abnormalities. This pattern suggests strong biases in the literature, with selective outcome reporting and selective analyses reporting being possible explanations.
Περιγραφή
Λέξεις-κλειδιά
Brain/*pathology, Humans, Mental Disorders/pathology, Meta-Analysis as Topic, Publication Bias/*statistics & numerical data
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
http://www.ncbi.nlm.nih.gov/pubmed/21464342
http://archpsyc.ama-assn.org/cgi/reprint/68/8/773.pdf
http://archpsyc.ama-assn.org/cgi/reprint/68/8/773.pdf
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