Bias in Periodontal Research

  • Alexandrina L. Dumitrescu


Bias is the systematic deviation of inferences or results from the truth, or processes that bring about such deviation. Biases can operate in either direction: Different biases can lead to underestimation or overestimation of the true intervention effect. Biases can vary in magnitude: some are small (and trivial compared with the observed effect) and some are substantial (so that an apparent finding may be entirely due to bias). Because the results of a study may in fact be unbiased despite a methodological flaw, it is more appropriate to consider risk of bias.


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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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