Strengths and limitations of randomized, controlled trials.
Sibinga
Erica M S
EM
Division of General Pediatrics & Adolescent Medicine, Johns Hopkins University, Baltimore, MD, USA.
Jennings
Jacky M
JM
D002648:Child; D003139:Common Cold / Q000178:diet therapy; D003627:Data Interpretation, Statistical; D006801:Humans; D019936:Probiotics / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic / Q000592:standards*; D012107:Research Design