Chapter 3 AN ONTOLOGY-DRIVEN APPROACH FOR ADHERENCE BEHAVIOUR
3.3 Comparison with the UPON Methodology
The ontology-driven approach is based on the UPON methodology. However, not all the UPON workflow activities were included directly in the approach. Table 3.1 below shows the UPON workflow activities as included in the ontology-driven approach. While some of the UPON workflow activities were directly included in the approach, others are modified and used as base knowledge to build activities included in the approach. Several activities were modified into steps that were found to be more appropriate for the representation of knowledge about adherence behaviour. However, there are some activities in the approach that are not explicitly included as activities in UPON methodology.
Determination of domain interest and scope was modified to determination of modelling scope. This is because the domain of interest, which is adherence behaviour, is already determined. The scope of the model to be developed is further constrained by the modeller in terms of disease and region of interest.
The use case description was simplified in the approach. The two activities of the Requirement workflow; writing one or more story boards and modelling the related use cases, were merged and simplified into one single use case description activity. The use case description activity for domain ontology development is not necessarily focused on application development. Adherence behaviour ontology does not require elaborate use case modelling, thus, a descriptive narration of the use case is the only detail required. Modelling of the use cases with a UML activity diagram was excluded from the approach. The usage scenarios were static single step activities without multiple actors and steps, as found in business processes. The narrative description of the use cases was sufficient for building the adherence ontology.
The building of the reference glossary was simplified and incorporated into the activities of the knowledge acquisition step. The UPON has elaborate activities for building reference glossaries are.
However, the required lexicons for the adherence ontology are identified and properly refined into a reference glossary through the two types of literature reviews in the knowledge acquisition step.
The review activities in the knowledge acquisition step are extensions made to UPON. Although UPON recognises the use of documented knowledge for the support of domain expert knowledge, the responsibility to establish domain concepts to be represented is based on the knowledge of an expert in the domain. The use of a single expert as the main source of reference knowledge was found to be inappropriate for adherence behaviour modelling. Adherence domain differs significantly from the business domain, where business processes and applications are explicit and well understood by single human expert. Hence, the knowledge acquisition step in the approach is based on a review of existing scientific literature which is used in the place of domain experts, as recommended by UPON. The motivation for using a literature review is described in detail in Section 3.2.2 above.
There are activities contained in the steps of the approach that led into the construction of a BN model for adherence: these activities are extensions to the UPON methodology. For instance, the BN concept and SAWP-Uncertainty ontology were included in the implementation of the ontology specifically for generating and representing a BN model. Also, an activity to demonstrate BN models construction was also included under the Ontology Evaluation step as a means to validate the usefulness of the ontology for predicting adherence risk. The ontology-driven approach takes into consideration the fitness of the adherence ontology for supporting predictive model construction and provides integrated activities that will guide researchers in developing an adherence ontology for this purpose. The construction of predictive models with the ontology is targeted at validating the usefulness of the ontology for predicting adherence risk.
UPON Workflows Activities Corresponding Activities in Ontology-driven Approach
Summary of Change Requirement Determine the domain of interest and the
scope
Determination of modelling scope The activity includes specifying disease and region of interest
Define business purpose Definition of design goals The goals must fit the purposes: capturing and representing specific factors, querying captured factors, building predictive models
Identify the competency questions(CQs) Definition of evaluation criteria The evaluation criteria include the criteria for model analysis and the CQs for the ontology evaluation Writing one or more story boards Description of use case The UPON activities were combined and simplified
into a single narrative of the ontology’s use case Modelling the related use cases.
Creating an application lexicon Review of existing adherence models
Collation of scientific evidence
The knowledge acquisition step covers the whole process of producing the reference glossary through a literature review
Analysis Acquire domain resources and build domain lexicon
Building Resource Reference Lexicon Building reference glossary
Modelling application scenario with UML Modelling with UML is not included in the approach Design Modelling Concepts Definition of model concepts Concept for representing scientific findings and BN
were recommended for consideration Modelling Concept hierarchies and domain
relationship
Definition of concept hierarchies Definition of relationships between concepts
Implementation Selecting a formal language Selection of a formal language, OWL and SWAP-Uncertainty ontology are
recommended as the formalisation of the adherence conceptual model and the BN concept respectively Formalising ontology Identification of exiting
ontologies
Formalisation of ontology
Test Consistency Checking Consistency checking
Answer competence questions (CQs) CQs answering
Verify coverage Comparative analysis with other
models
Coverage verification process is moved to the Model Analysis step and is comprised of these activities Adherence knowledge
classification with the model
Table 3.1: UPON Workflow and Ontology-driven Approach activities