The Building of a Virtual Individual Model (VIM): Multi Domain Characterisation of Health Status in the PEGASO Project
Authors: L. Lafortunaa Claudio , C. E. Serranob José , S. Coulsonc Neil 
Published: February 2022

The recent European strategies for the improvement of citizens’ health status largely rely upon the promotion of technological solutions that empower the individual as a co-producer of his/her health through the management of personal life conditions, with a user-centred approach. The efficacy of this approach is enhanced by a detailed and accurate modelling of knowledge concerning the individual's health requirements. Moreover, the adoption of a Virtual Individual Model (VIM) including biological, cognitive and social aspects in the framework for health status characterisation may lead to a stronger empowerment of the user through a more individualised strategy of health management. Purpose of this work is the presentation of a VIM structure suitable to describe obesity related phenomena in children and adolescents. The model includes physical, physiological and psychological domains which are ruled by specific behaviours and influenced by societal externalities, and ultimately concur to the concept of whole individual's health, defined as "a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity". It is assumed that health status is primarily settled on elements of physical status of body structure (comprising body size and composition attributes), physiological status (comprising metabolic parameters related to alimentary habits and functional responses to exercise) and psychological status (based on relevant characteristics of personality). Body structure and functionality are influenced by the individual's behaviours in the domains of alimentation and physical activity, which are driven by relevant aspects of motivation. Social status, social behaviour and psychological status (i.e. the psychosocial factors) are considered in the model as important determinants of behavioural skills as well as attitudes and motivation to engage in healthy lifestyle behaviours. In such a context, status and behaviours in the different domains can be defined by appropriate profiling including parameters relevant for quantitative characterisation and detection of changes, whereas motivation for healthy lifestyles can be evaluated through changes in alimentary and/or physical activity behaviours. Thus the VIM results to be built on profiles spanning from physical to psychological and social domains and include aspects of different behaviours, each component of the model being modifiable by the other components and determining dynamically the individual's health status. The so defined VIM will be suitable to be handled with ontology-driven tools allowing to outline the semantic relations between the different elements in the biological, cognitive and social domains and dynamically enabling inferences over individual-related parameters spanning through the different domains. Moreover, the use of VIM within the PEGASO project, will facilitate the creation of both the whole multi-dimensional and cross-disciplinary ICT system architecture as well as the development of dedicated reasoners for the inference of the health status and the promotion of alimentary-/exercise-related healthy behaviours, relevant for overweight and obesity prevention in the juvenile age.