The randomised controlled trial to meta-analysis ratio: original data versus systematic reviews in the medical literature.
Bolland
Mark J
MJ
Grey
Andrew
A
Reid
Ian R
IR
D016239:MEDLINE / Q000706:statistics & numerical data; D015201:Meta-Analysis as Topic; D010506:Periodicals as Topic / Q000706:statistics & numerical data* / Q000639:trends; D016032:Randomized Controlled Trials as Topic; D012196:Review Literature as Topic