title: The effect of variance function estimation on nonlinear calibration inference in immunoassay data.
abstract: Often with data from immunoassays, the concentration-response relationship is nonlinear and intra-assay response variance is heterogeneous. Estimation of the standard curve is usually based on a nonlinear heteroscedastic regression model for concentration-response, where variance is modeled as a function of mean response and additional variance parameters. This paper discusses calibration inference for immunoassay data which exhibit this nonlinear heteroscedastic mean-variance relationship. An assessment of the effect of variance function estimation in three types of approximate large-sample confidence intervals for unknown concentrations is given by theoretical and empirical investigation and application to two examples. A major finding is that the accuracy of such calibration intervals depends critically on the nature of response variance and the quality with which variance parameters are estimated.
authors.affiliation: Schering-Plough Research Institute, Kenilworth, New Jersey 07033, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Belanger
authors.forename: M
authors.initials: M
authors.lastname: Davidian
authors.forename: D M
authors.initials: DM
authors.lastname: Giltinan
mesh_terms: D000465:Algorithms; D000704:Analysis of Variance; D000818:Animals; D001699:Biometry / Q000379:methods*; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards / Q000706:statistics & numerical data; D006801:Humans; D007118:Immunoassay / Q000592:standards / Q000706:statistics & numerical data*; D009010:Monte Carlo Method; D017711:Nonlinear Dynamics; D004364:Pharmaceutical Preparations / Q000032:analysis / Q000592:standards; D011863:Radioimmunoassay / Q000592:standards / Q000706:statistics & numerical data; D011994:Recombinant Proteins / Q000032:analysis; D012015:Reference Standards; D012065:Relaxin / Q000032:analysis; D013552:Swine
chemical_list: D004364:Pharmaceutical Preparations; D011994:Recombinant Proteins; D012065:Relaxin