Randomized trials and observational studies: still mostly similar results, still crucial differences.
Kunz
Regina
R
Basel Institute for Clinical Epidemiology, University Hospital Basel, Hebelstrasse 10, 4031 Basel, Switzerland. rkunz@uhbs.ch
D019317:Evidence-Based Medicine / Q000379:methods; D006801:Humans; D019370:Observation; D016032:Randomized Controlled Trials as Topic; D012107:Research Design; D016896:Treatment Outcome