Search PubMed⌕ Search

PubMed · 8685079

Calculating predictive performance: a user's note.

Abstract

The method proposed by Sheiner and Beal plays a cornerstone role in the evaluation of the predictive performance. Recently, the Sheiner and Beal's method has been intensively used in pharmacokinetic studies, however, this method has been used in a somewhat confusing way by several authors. Therefore, if one wants to use this method, one might find different examples to follow in the pharmacokinetic literature. Meanwhile, several detailed points were not given by Sheiner and Beal in their original paper. Clearly, the principles suggested by Sheiner and Beal are simple, but the practical application is something of an art. In this work we addressed these detailed points and indicated the confusion in using the Sheiner and Beal's method.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

G Wu. 1995. Calculating predictive performance: a user's note.. https://doi.org/10.1016/1043-6618(95)80095-6

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Evaluation and comparison of therapeutic monitoring of whole-blood levels of cyclosporin A and its metabolites in renal transplantation by HPLC and RIA methods.

BACKGROUND: The aim of the work was to evaluate the possibility to estimate the level of cyclosporin A (CyA) metabolites as the difference of radioimmunoassay (RIA) non-specific and RIA specific methods. METHODS: Blood samples of renal transplant patients were analyzed by three different methods: RIA specific method (CYCLO-Trac, DiaSorin, USA) (RIA(SP)), RIA non-specific method (Immunotech, Czech Republic) (RIA(NS)), and high performance liquid chromatography (HPLC) method. RESULTS: Although values obtained by RIA(SP) correlated well those obtained by HPLC (RIA(SP)=0.995.HPLC+9.68; r(2)=0.962, n=448), the results of HPLC methods were lower by 8%. The values obtained by RIA(NS) were 2.57 times higher than the values obtained by RIA(SP) (RIA(SP)=0.356RIA(NS); r(2)=0.713, n=448). The ratio (CyA+CyA metabolites)/(CyA) calculated as the ratio RIA(NS)/RIA(SP) values for 42 renal transplant patients was relatively stable for each particular patient. The sum of selected CyA metabolites (M1+M17+M21) measured by HPLC correlated well with that estimated from the difference of RIA(NS)-RIA(SP): HPLC(metab)=0.921.(RIA(NS)-RIA(SP))+21.3; (r(2)=0.746, n=448). CONCLUSION: The combination of both the specific and non-specific methods for the determination of CyA presents an improved means for the TDM of CyA and CyA metabolites in renal transplant patients. Moreover, a combination of both methods can help to elucidate some unexpected events, such as the persistence of high cyclosporin blood levels.

Blood Chemical Analysis↗