Are observational studies 'just as effective' as randomized clinical trials?
Greene
T
T
Department of Biostatistics and Epidemiology/Wb4, The Cleveland Clinic Foundation, Cleveland, Ohio, USA. tgreene@bio.ri.ccf.org
D006801:Humans; D019370:Observation / Q000379:methods*; D015588:Observer Variation; D016032:Randomized Controlled Trials as Topic / Q000379:methods* / Q000592:standards; D006435:Renal Dialysis / Q000379:methods / Q000592:standards; D012107:Research Design