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Toward an ontology of tobacco, nicotine and vaping products.

BACKGROUND AND AIMS
Ontologies are ways of representing information that improve clarity and the ability to connect different data sources. This paper proposes an initial version of an ontology of tobacco, nicotine and vaping products with the aim of reducing ambiguity and confusion in the field.


METHODS
Terms related to tobacco, nicotine and vaping products were identified in the research literature and their usage characterised. Basic Formal Ontology was used as a unifying upper-level ontology to describe the domain, and classes with definitions and labels were developed linking them to this ontology. Labels, definitions and properties were reviewed and revised in an iterative manner until a coherent set of classes was agreed by the authors.


RESULTS
Overlapping, but distinct classes were developed: 'tobacco-containing product', 'nicotine-containing product' and 'vaping device'. Subclasses of tobacco-containing products are 'combustible tobacco-containing product', 'heated tobacco product' and 'smokeless tobacco-containing product'. Subclasses of combustible tobacco-containing product include 'cigar', 'cigarillo', 'bidi' and 'cigarette' with further subclasses including 'manufactured cigarette'. Manufactured cigarettes have properties that include 'machine-smoked nicotine yield' and 'machine-smoked tar yield'. Subclasses of smokeless tobacco product include 'nasal snuff', 'chewing tobacco product', and 'oral snuff' with its subclass 'snus'. Subclasses of nicotine-containing product include 'nicotine lozenge' and 'nicotine transdermal patch'. Subclasses of vaping device included 'electronic vaping device' with a further subclass, 'e-cigarette'. E-cigarettes have evolved with a complex range of properties including atomiser resistance, battery power, properties of consumables including e-liquid nicotine concentration and flavourings, and the ontology characterises classes of product accordingly.


CONCLUSIONS
Use of an ontology of tobacco, nicotine and vaping products should help reduce ambiguity and confusion in tobacco control research and practice.