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Point and Interval Estimates of IC_50 by Line Approximation

J. Knizek, P. Tomsik, L. Beranek, E. Rudolf, S. Micuda, L. Sucha, M. Razacova


When computing IC_50 in experiments which assess the inhibitory effect of tested compounds or physical agents, one is often restricted by a low number of measurements. This paper shows how to progress when only limited data are available. In these cases, a line approximation for the practical computing of IC_50 appears as the most suitable method. In this study, we focus on how to solve the problem of the insufficient number of x-axis points n by optimizing linear regression. Our conclusions are also demonstrated on real data from medical biochemistry.


Inhibitory concentration; Biochemistry; Line approximation; Point estimate of IC_50; Interval estimate of IC_50; Applied statistics.

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