Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1988-8-17
pubmed:abstractText
A number of biological, dosimetric, and statistical problems encountered in the determination of alpha/beta ratios and the relative biological efficiency (RBE) of high energy electrons are discussed. The analysis is based on isoeffect dose determination from logit analysis of dose-response data. Monte Carlo simulations of the logit analysis show that the estimated isoeffect dose may be treated as a normally distributed random variable. Under this assumption, formulae for the standard error of the derived radiobiological parameters are presented. The importance of specifying not only parameter estimates but also their confidence limits is emphasized. As a practical example, the dose-response relationships for severe erythema and subcutaneous fibrosis are discussed in two series of patients treated with postmastectomy irradiation with electrons and photons in two fractionation schedules. Because of a different dose per fraction in the electron and photon fields, a determination of RBE requires a fraction size correction. This is performed using the alpha/beta formalism. The present analysis suggests a high energy electron RBE for severe erythema of 0.93 (95% confidence limits 0.89 and 0.96) and for subcutaneous fibrosis of 0.84 (95% confidence limits 0.77 and 0.92).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0284-186X
pubmed:author
pubmed:issnType
Print
pubmed:volume
27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
105-16
pubmed:dateRevised
2009-5-12
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Some methodological problems in estimating radiobiological parameters from clinical data. Alpha/beta ratios and electron RBE for cutaneous reactions in patients treated with postmastectomy radiotherapy.
pubmed:affiliation
Department of Oncology, Radiumstationen, Aarhus C, Denmark.
pubmed:publicationType
Journal Article