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PubMed · 2727895

A direct method for estimating the alpha/beta ratio from quantitative dose-response data.

M Stuschke
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Abstract

A one-step optimization method based on a least squares fit of the linear quadratic model to quantitative tissue response data after fractionated irradiation is proposed. Suitable end-points that can be analysed by this method are growth delay, host survival and quantitative biochemical or clinical laboratory data. The functional dependence between the transformed dose xn (dn) = n (alpha dn + beta dn2) and the measured response is approximated by a polynomial. The method allows for the estimation of the alpha/beta ratio and its confidence limits from all observed responses of the different fractionation schedules. Censored data can be included in the analysis. A method to test the appropriateness of the fit is presented. A computer simulation illustrates the method and its accuracy as examplified by the growth delay end point. A comparison with a fit of the linear quadratic model to interpolated isoeffect doses shows the advantages of the direct method.

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BibTeXRIS

M Stuschke. 1989. A direct method for estimating the alpha/beta ratio from quantitative dose-response data.. https://pubmed.ncbi.nlm.nih.gov/2727895/

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