Year: 2013
Type: article
Abstract: In many biological and environmental studies, measured data is subject to a limit of detection. The limit of detection is generally defined as the lowest concentration of analyte that can be differentiated from a blank sample with some certainty. Data falling below the limit of detection is left censored, falling below a level that is easily quantified by a measuring device. A great deal of interest lies in estimating the limit of detection for a particular measurement device. In this paper, we propose a change-point model to estimate the limit of detection by using data from an experiment with known analyte concentrations. Estimation of the limit of detection proceeds by a two-stage maximum likelihood method. Extensions are considered that allow for censored measurements and data from multiple experiments. A simulation study is conducted demonstrating that in some settings the change-point model provides less biased estimates of the limit of detection than conventional methods. The proposed method is then applied to data from an HIV pilot study.
Source: Statistics in Medicine
DOI: 10.1002/sim.5872
Language: English
Subfield: Statistics, Probability and Uncertainty
Field: Decision Sciences
Domain: Social Sciences
Open Access status: bronze
Awards: International Network for Strategic Initiatives in Global HIV Trials (INSIGHT), G533257933, G696308980, G7966639343, Statistical Issues in AIDS Research, G9000085426, G9000107377, Biostatistics for Research in Genomics and Cancer, The University of North Carolina Center for AIDS Research, Statistical Issues in AIDS Research
OpenAlex ID: W2167090627