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Randomized Controlled Clinical Trials

  • Alexandrina L. Dumitrescu
Chapter
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Abstract

The randomized clinical trial (RCT) is a research design used to compare two or more forms of therapy. Four traits that distinguish an RCT from routine clinical care are (1) an RCT is controlled (all subjects in the RCT are selected based upon stringent predetermined entrance criteria), (2) it is randomized (subjects are assigned to treatment groups by chance, independent of their individual characteristics), (3) the final outcome is established through statistical analysis (criteria are established for measuring differences among the two groups prior to initiation of the study, and the data are analysed to determine of the preset level of significance is obtained), (4) most often, a double-blind technique is employed.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Alexandrina L. Dumitrescu
    • 1
    • 2
  1. 1.Department of PeriodontologyUniversity of Tromsø Institute of Clinical DentistryTromsøNorway
  2. 2.Private practiceBucharestRomania

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