Abstract: An adaptive computer-implemented e-learning system and method able to deliver a learning approach that customizes and adapts to each learners' skills and knowhow. A computer-implemented cognitive diagnosis process for predictions on skills and knowledge of a learner comprising the steps of: building a domain ontology; establishing a items bank; referencing the items bank using elements from the domain ontology elements (semantic-grounding of the items); establishing a training database of learners answers; estimating Cognitive Diagnostic Model (CDM) parameters and determining an appropriate model to be used; running the model to estimate a learner level on non-abstract latent variables; applying a Mastery of domain Knowledge and competency Skill (MKS) approach to estimate the learner level on abstract latent variables, or extracting relevant hierarchies from the ontology and use the CDM appropriate model to estimate those attributes; and building a diagnosis report from the results of steps 6) and 7).