Need for placebo period in antihypertensive trials.
D002986:Clinical Trials as Topic; D006801:Humans; D006852:Hydrochlorothiazide / Q000627:therapeutic use*; D006973:Hypertension / Q000188:drug therapy*; D010919:Placebos
D010919:Placebos; D006852:Hydrochlorothiazide