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E-books / Guide to GUTS

Information about "GUTS, a comprehensive guide"

This page contains information about the e-book on GUTS entitled: "Modelling survival under chemical stress. A comprehensive guide to the GUTS framework." The first version was released on 18 January 2018. This book is co-written by Tjalling Jager and Roman Ashauer, as part of a Cefic-LRI funded project. The book contains a detailed description of GUTS (both conceptual and mathematical), its special cases, and the associated statistics. Case studies will be included to illustrate how to use GUTS on actual data sets, and much, much more.
The book is offered through the Leanpub publishing framework. As with the other e-books, you have the opportunity to download it for free, but you also have the option to pay for it. Please consider this option, for it will allow us to dedicate time and effort to updating this e-book, and writing new ones. In any case, it is good to download this e-book from Leanpub yourself, as you will be informed automatically when we release a new version.
  • You can download the e-book from this landing page at Leanpub (Version 2.1 of 21 November 2022) or check out the first 15 pages here.
  • Check the version/error log for changes relative to the previous version, known errors in the current version, and parts that we will modify/clarify in the next update.
  • Check out the list of survival papers over here. At this moment, the list only contains papers using the hazard formulation (i.e., GUTS-SD, GUTS-RED-SD, and its predecessors).

How do I refer to the book?

Please refer to the Leanpub page with the version of the PDF. E.g.:
  • Jager T and Ashauer R (2022). Modelling survival under chemical stress. A comprehensive guide to the GUTS framework. Version 2.1. Toxicodynamics Ltd., York, UK. Available from Leanpub:
As general reference to GUTS, you can use the paper in the open literature:
  • Jager T, Albert C, Preuss TG and Ashauer R (2011). General Unified Threshold model of Survival - a toxicokinetic-toxicodynamic framework for ecotoxicology. Environ Sci Technol 45:2529-2540. 

Where can I find software to do 'GUTS' analyses?

In 2018/2019 we have developed the free, open source, user-friendly, Windows-based, standalone software openGUTS in a Cefic-LRI funded project. In my (admittedly biassed) opinion, this is the best GUTS software out there. There is also a Matlab version of openGUTS with the same engine and roughly the same functionality, which served as the blueprint and testing platform for the standalone software. Both can be downloaded from the dedicated openGUTS website. OpenGUTS only contains the simplest GUTS cases GUTS-RED-SD and GUTS-RED-IT.

There is also a BYOM package for GUTS that allows all GUTS cases to be run. Links to other freely-downloadable software (such as two R-packages for GUTS, and several other standalone versions) are collected over here. In the book, we also present the results from a ring test with 11 software implementations. Not all of them are available yet for free-downloadable yet (they will be included in the software section of this website when they do), and the ring test is in need for an update.

Ring test information

Data sets used for the GUTS ring test (as presented in Appendix A of the e-book) can be downloaded here as Excel file.

A detailed listing of the parameter estimates and predictions (with confidence intervals) for the BYOM analyses has been collected into a report. Download here. This is an updated version, using BYOM v. 4.2b and GUTS v. 2.2 (both with a few updates to increase speed and accuracy, and correcting a small error). There are some differences with the earlier BYOM analysis (as went into the e-book), which are discussed in the PDF. Filesize is pretty large due to the parameter-space plots that I included. This is the version of 19 August 2018 (note that the version of 15 Aug. 2018 contained a silly error in calculations involving time-varying concentrations).

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