Interpolation in Assay Systems with a Sigmoid Response Curve

  • Kurt R. S. Osterloh
  • Geoffrey D. Smith
  • Timothy J. Peters


A procedure to facilitate interpolation of results from sigmoid curves, e.g. immunoradiometric assays, radioimmunoassay, titration curves, dose-response curves, is presented. The procedure allows curve fitting even where the zero and/or 100% values are unknown. A minimum and a maximum value are found by the program with pairs of abscissa and ordinate values as the only input information. The data may be weighted. In addition, the program provides information about the point of inflection of the sigmoid curve in order to estimate a 50% response value, which is not always provided in other program-fitting sigmoid curve procedures.


Titration Curve Polynomial Regression Sigmoid Curve Immunoradiometric Assay Statistical Quality Control 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© The Editor and Contributors 1989

Authors and Affiliations

  • Kurt R. S. Osterloh
  • Geoffrey D. Smith
  • Timothy J. Peters

There are no affiliations available

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