Data use and generation in current and future model implementations. In the current study, we used Particle Profiler as indicated below the vertical bar. Pooled lipoprotein flux data was used for fitting the model to data of individual subjects, and the fitted model was used to generate lipoprotein particle flux data and lipoprotein metabolic ratios. The light blue area illustrates the final application we aim at. In that application, Particle Profiler will be applied to lipoprotein profile data, which allows for the quantification of lipoprotein metabolic ratios only.