Demetra models were developed to comply with the OECD principles for validation of QSARs for regulatory use. For example:

1. The endpoints are clearly identified. Furthermore, we have identified the regulation addressed by the QSAR model, the related guidelines for toxicity experiments satisfying the regulation, and only toxicity data obtained according to these guidelines have been used.
2. The models have been fully described in the Demetra book. In addition, particular aspects of the models have been reported in a number of papers. All toxicity data and chemical descriptors are available. For maximum transparency and reproducibility, all model algorithms have been codified in xml.
3. The applicability domain of each model has been fully described and commented in the Demetra book. Briefly, the models are for pesticides and not suitable for inorganic compounds and mixtures. Specific restrictions apply for some models, and they have been listed in the user manual. Alternatively you can read theusing Demetra Tool - Online Tutorial
4. The Demetra models have been tested with internal validation techniques (leave-one-out, y-scrambling) and with external test sets. Good results have been obtained. Full validation results are presented in the Demetra book.
5. On the basis of the selected descriptors, some likely mechanisms can be identified. For instance, logP has been identified as an important descriptor for aquatic endpoints, but not for terrestrial ones. Specific fragments, such as carbamate, has been identified as related to greater toxicity in some cases. Full details of these aspects are also reported in the Demetra book.