=Paper= {{Paper |id=Vol-2137/ws_ONCONTO_paper_3.pdf |storemode=property |title=Ontology of Cancer Related Social-Ecological Variables |pdfUrl=https://ceur-ws.org/Vol-2137/ws_ONCONTO_paper_3.pdf |volume=Vol-2137 |authors=Dharani K. Balasubramanian,Jamillah Z. Khan,Jiang Bian,Yi Guo,William R. Hogan,Amanda Hicks |dblpUrl=https://dblp.org/rec/conf/icbo/Balasubramanian17 }} ==Ontology of Cancer Related Social-Ecological Variables== https://ceur-ws.org/Vol-2137/ws_ONCONTO_paper_3.pdf
                Ontology of cancer related social-ecological variables
       Dharani K. Balasubramanian1,*, Jamillah Z. Khan1, Jiang Bian1, Yi Guo1, William R
                                 Hogan1, Amanda Hicks1
                                  1
                                   Department of Health Outcomes and Policy, University of Florida, USA



ABSTRACT                                                                         approach can be used in improving health outcomes by taking
    Several social-ecological (SE) factors affect human behavior. Analysis
                                                                                 steps to intervene on the variables of influence (Diez-Roux,
of these factors is an integral part of behavior research. An efficient method
of scrutinizing these predictors is multilevel analysis. Social Ecological       2000). By integrating data with the help of OCRSEV (K.
Model (SEM) is a multilevel framework that helps to capture all the variables    Balasubramanian, 2017), multilevel analysis of SE predictors
at five levels: individual, interpersonal, organizational, community, and        can be performed.
policy. This work aims to develop a reference ontology with classes that
correspond to SE predictors that influence cancer diagnosis, beginning with         Social Ecological Model (SEM) is a conceptual model that
the individual level of SEM. This ontology is built with an aim to aid data      has been in use in the public health community as the
integration in order to carry out multilevel analysis of the integrated data.    foundation of multilevel intervention design and
The broad hypothesis is that, if all the variables gathered from various
sources and at different levels of the SEM are configured in an ontology,        implementation (Moore A et al., 2015). SEM helps to explore
there will be enough information to identify and visualize association           the predictors of a disease at multiple levels and analyze
between these variables and health outcomes. This work is focused on 13 SE       them. There are several SE factors contributing to a wide
variables which were first identified by performing a scoping literature
review. Manually curated terms corresponding to these variables were
                                                                                 range of health disparities in society (Adler & Newman,
aligned with existing ontology classes. The ontology of cancer related social-   2002). In this work, we refer to the SEM of health promotion
ecological variables (OCRSEV) is built upon the Basic Formal Ontology 2.0        (CDC – Social Ecological Model – CCRP, 2017) to stratify
(BFO 2.0) and conforms to Open Biomedical Ontologies (OBO) Foundry’s             the SE variables of late-stage cancer diagnosis (LSCD). The
best practices. Future work is planned to extend the ontology for variables in
other levels of SEM and map the PCORnet Common Data Model (PCORnet               SEM framework has five levels: individual, interpersonal,
CDM) data and other relevant data with these variables in the ontology.          organizational, community, and policy. The theory of SEM
                                                                                 model implies that the individual is the target of this
1 INTRODUCTION                                                                   interrelated system, placing the individual in the center of the
   One of the greatest advances in explaining the predictors                     model and all other levels representing SE variables around
of disease is the identification of social and psychological                     the individual level in a concentric manner (Fig. 1). When
conditions of individuals (Chapter 4: Social Risk Factors,                       each of those variables is identified and analyzed, public
2001). These conditions may influence the morbidity and                          health activities can be implemented at each level, thereby
mortality directly through physiological processes and                           increasing synergies of intervention to improve the overall
indirectly through behavioral pathways. People living in                         health outcomes of individuals.
areas with socioeconomic disadvantages and cultural barriers
such as lack of health insurance, low income level, and
negative opinions toward cancer screening are more likely to
be diagnosed with cancer at late-stage (Wang, Luo and
McLafferty, 2010). Treatment is less effective and there is a
lower chance of survival with those who have late-stage
diagnosed. It is critical to identify and enhance methods to
detect cancer at an earlier stage. Earlier cancer diagnosis
would save tens of millions of dollars annually and increase
chances of effective treatment and survival (Why is early
diagnosis important?, 2015).
   Multilevel analysis in public health research is a statistical
strategy which involves parallel examinations of individual
                                                                                   Fig. 1. Social Ecological Model, adapted by the CDC (CDC –
and group level factors. This method has a hierarchical                                      Social Ecological Model – CCRP, 2017).
approach with multiple levels that classify factors. This

*
    To whom correspondence should be addressed: kbdhaar@ufl.edu



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                                                                           Ontology of cancer related social-ecological variables



   The structure of this ontology is based on Web Ontology        different sources such as PubMed, Web of Science, Google
Language 2 (OWL 2) models for different individual level SE       Scholar, etc., that affect cancer diagnosis. A total of 79, 29,
variables and their relations with the SEM. For our use-case,     59, 62 and 36 variables were collected for cancer types breast,
and because this study focused on individual-level variables      lung, prostate, colon/colorectal and cervical respectively
affecting cancer diagnosis, we investigated five databases        from a total of 43 articles. The variables from the literature
with Florida patient data and selected one that relates the       were then extracted and stratified into the five levels of SEM.
most to the individual factors of the SEM. The PCORnet               As a preliminary step in constructing the ontology, the
Common Data Model (CDM) conveys a specification that              most common individual-level variables were selected to be
defines a standard organization and representation of data for    used in the development of our ontology. A total of 13
the PCORnet Distributed Research Network. (PCORnet                variables were selected: comorbidity, age, blood pressure,
Common Data Model – PCORnet, 2017). This CDM holds                body mass index range, education, employment, income
patient-centered data that include many individual-focused        status, medical cost, socioeconomic status, tobacco-use,
variables such as demographics and vitals. With this model,       ethnicity, race and gender. The references for these variables
relevant data from any PCORnet database can be mapped             can be found on GitHub (K. Balasubramanian, 2017). Of
with its corresponding classes in the ontology.                   these variables, gender, ethnicity, race and tobacco-use can
   Semantic data integration (SI) combines heterogeneous          be found in PCORnet CDM.
data from various sources and integrates them by leveraging          The competency questions (CQ) used in the development
the semantic content that is embedded in these sources            of this ontology are:
(Livingston et al., 2015). It brings together data from various     (1) What are some diseases that are cancer?
sources by relating the true meaning of data from one source        (2) What are some parts of SEM that are levels?
with another. Ontology mapping is key to SI of data which           (3) What are some variables represented by SEM?
helps to identify similarities between ontologies and               (4) What are some variables represented by the SEM at the
determine the concepts that represent these correspondences               individual level?
in order to enable reasoning. Other data integration methods        (5) What are some variables represented by the SEM at the
may not use semantic standards, which are mandatory to                    individual level, that are also present in PCORnet
define the meaning of the data and finding its roots (Noy,                CDM database?
2004). Our ontology can be extended for other levels of SEM         (6) What are some variables represented by the SEM at the
and linked with corresponding data from different databases               individual level, that are also present in PCORnet
thereby providing semantic data integration.                              CDM database and are identity data?
   The Ontology for Medically Related Social Entities                 Based on these competency questions, reusable classes
(OMRSE) (Hogan, Garimalla, & Tariq, 2011)(Hicks et al.,           and object properties from existing ontologies relating to our
2016) covers the domain of social entities related to             13 variables and the five cancer types were identified using
healthcare and is similar to OCRSEV as it includes terms          Ontobee (Ontobee, 2017) and BioPortal (NCBO BioPortal,
describing SE variables such as demographics, but different       2017). The ontology was developed in Protégé 5.1 (Research,
in the sense that it does not follow a multi-level model          2017) and conforms to OBO Foundry’s (Smith et al., 2007)
approach. OCRSEV is useful in knowledge representation of         best practices. The upper-level ontology is BFO 2 (Grenon &
SE variables and specifying their level in SEM.                   Smith, 2004; Arp et al., 2015). Ontofox (Xiang et al., 2010)
                                                                  was used to import the ontologies and the individual terms
Scope of the Ontology: The ontology will include terms that
                                                                  for this project.
are related to SE variables of five types of cancer diagnosis
namely breast, cervical, lung, prostate and colon/colorectal.      Imported Ontologies: The structure of the ontology was
The ontology will focus on some of the key variables in the       heavily influenced by OMRSE. OMRSE utilizes BFO as its
individual level of SEM. The specific aims of this project are:   upper-level ontology. OMRSE has many classes that are
  ● To collect SE variables related to cancer and those which     reused in OCRSEV. The Vital Sign Ontology (VSO)
     act as possible determinants of late-stage cancer            (Goldfain et al., 2011) also uses BFO as its upper-level
     diagnosis based on a scoping literature review               ontology and focuses on vital sign measurement data, vital
  ● To develop an ontology for SE factors responsible for         sign measuring processes, and devices used to measure
     cancer diagnosis at the individual level of SEM.             human vital signs. OMRSE, along with VSO were both
  ● To include those variables that match with the individual     imported ontologies. Classes related to “blood pressure” from
     level variables in PCORnet CDM.                              VSO are reused in OCRSEV. The two selected ontology
                                                                  imports serve as a foundation for the creation of this ontology
2 METHODS                                                         and provides the skeleton of the future work which involving
  This work involved performing a scoping literature review       the inclusion of variables beyond the individual-level.
(Arksey et al., 2007) to collect all the SE variables from



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                                                                            Ontology of cancer related social-ecological variables



Imported terms: Apart from entire ontologies, some classes         comorbidity” was created as a subclass of “comorbidity” and
and relations were also imported for the construction of           defined as a comorbidity with a primary diagnosis of cancer.
OCRSEV. A total of 70 terms were imported from the Human           This was required to relate comorbidity with cancer. “tobacco
Disease Ontology (DOID) (Kibbe et al., 2014) for the five          use role” and “tobacco use behavior” were created according
types of cancer (cervical cancer, colon cancer, breast cancer,     to the model created for “individual tobacco use range
lung cancer, prostate cancer). The terms were arranged in          variable”. For the PCORnet database and variables,
BFO 2 following the hierarchy of the Cell Line Ontology            “PCORnet CDM database” was created as a subclass of
(CLO) (CLO, 2017). “Body Mass Index” was imported from             “database” imported from ERO (Fig. 2) first and then,
Clinical Measurement Ontology (CMO) (Shimoyama et al.,             “PCORnet tobacco use range variable” was created as a
2012; Smith et al., 2013). To determine where to place this        subclass of “individual tobacco use range variable”.
class in BFO 2, the same class from Taxonomy for
Rehabilitation of Knee Conditions (TRAK) (Button et al.,
2013) was referred to.
   Existing definitions for variables such as comorbidity, age,
weight, and height encouraged us to reuse these definitions in
place of creating our own definitions. “Comorbidity” was
imported from the Ontology for Minimum Information
About Biobank data Sharing (OMIABIS) (Brochhausen et
al., 2013), and qualities such as “height” and “weight” were                  Fig. 2. Variable terms and database terms
imported using the Phenotypic Quality Ontology (PATO)
(WG, 2017). “Age” used for modeling the created term “age
range variable” was imported from Ontology for Biomedical
Investigations (OBI). Since OCRSEV is constructed with
numerous variables and categorical variables, classes
“variable” which is a subclass of “data item” and “categorical
variable” which is a subclass of “variable” were reused from
Apollo Structured Vocabulary (Apollo SV) (Hogan et al.,
2016).
   “Hypertension” and its related classes were imported from
Obstetric and Neonatal Ontology (ONTONEO) (Farinelli et
al., 2016) as they are useful creating class restrictions in the                     Fig. 3. Identity datum terms
model for one of the created classes “blood pressure range             The class “model” was created as a subclass of “directive
variable”. “tobacco”, “tobacco material”, “chewing tobacco         information entity” in BFO following the placement of “data
behavior”, “smoking behavior” and related classes were             representational model” from Apollo SV. Since SEM of
imported from Ontology for Biobanking (OBIB)                       health promotion is a model that represents SE variables and
(Brochhausen et al., 2016) as they were useful in developing       is encoded in the specification of CDC’s SEM, CCRP, 2015,
the model for the created class “individual tobacco use            this model is a directive information entity, similar to the
variable”. Since the ontology uses PCORnet CDM database            “data representational model” from Apollo SV. “Multilevel
variables, the class “database” was imported from Eagle-I          model” was created as a subclass of “model” and “socio-
Research Resource Ontology (ERO) (Vasilevsky et al.,               economic model” was created as a subclass of “multi-level
2012).                                                             model”. “Socio ecological model level” which is a part or a
Created Classes: SE variables were created as subclasses of        component of the socioecological model was created as a
categorical variable. The classes include “age range               subclass of “information content entity”. The five levels of
variable”, “individual tobacco use variable”, “individual          socio-ecological model, namely, “socio ecological model
education level variable”, “individual employment status           individual level”, “socio ecological model interpersonal
variable”, “individual income status variable”, “individual        level”, “socio ecological model organizational level”, “socio
socioeconomic status variable”, “individual medical cost           ecological model community level” and “socio ecological
variable”, “body mass index range variable” and “blood             model policy level” were created as subclasses of “socio
pressure range variable”. This covers nine of 13 variables         ecological model level” (Fig. 4). The class “body mass” was
(Fig. 2). Of the remaining four variables, three classes,          created as a subclass of “mass” in quality of BFO, as required
namely, “racial identity datum”, “ethnic identity datum” and       by the model created for “body mass index range variable”.
“gender identity datum” were reused from OMRSE while               Although “body mass” is available in Vertebrate Trait (VT)
“comorbidity” was reused from OMIABIS. “Cancer



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                                                                                              Ontology of cancer related social-ecological variables



ontology (Park C et al., 2013), we did not reuse this class as                   social         social        A social ecological model level which
                                                                                 ecological     ecological    represents the social variables influencing an
VT does not have BFO as its upper level ontology.                                model          model level   individual or a population, specifically
                                                                                 policy                       containing variables related to Medicare and
                                                                                 level                        Medicaid at population level, including
                                                                                                              proportion of population in managed care health
                                                                                                              plan and proportion of vulnerable cancer
                                                                                                              population.
                                                                                    Table 1 Competency Questions, Description Logic queries, and
                                                                                                  expected results for validation
             Fig. 4. Social ecological model and its levels                      Class restrictions: To create class restrictions for the created
   Classes “PCORnet ethnicity identity datum” and                                classes, object properties such as “part of”, “has part”, “is
“PCORnet racial identity datum” and their subclasses were                        about”, and “inheres in” were used. Some relations such as
used from the model created for PCORowl by OneFlorida                            “correlated with” were imported from Relations Ontology
team at the University of Florida (Fig. 3) (Hicks et al., 2017).                 (RO) (Mungall, 2017) to relate the qualities or roles of the
                                                                                 variables with cancer. From the literature review, we could
Definitions: WordNet (Miller, 1990) and NCI Thesaurus                            say that some of the variables discussed in this paper are
(Sioutos et al., 2007), Wikipedia (Wikipedia, 2017), Medical                     “correlated     with”     the    condition      “cancer”     (K.
Subject Headings (Medical Subject Headings, 2017), Apollo                        Balasubramanian, D., 2017). “is determined by” and
SV, PATO and other existing ontologies were referred to for                      “determines” were imported from The Drug-Drug
crafting the definitions and modified as required based on the                   Interactions Ontology (DINTO) (Herrero-Zazo et al., 2015)
requirement and genus proximus (Seppälä et al., 2016) for all                    to relate the variables with qualities or other conditions. For
the terms created in OCRSEV. CDC’s SEM for CCRP and                              example, since “body mass index” is a measurement of
Wikipedia were referred for crafting definitions of SEM and                      related body weight to height of an individual, we can say
its levels. SEM levels’ definitions are in Table 1.                              that “body mass index” is determined by “height” and
Class         Genus       Definition                                             “weight”. As an overall structure, all 13 variables are a “part
              Proximus                                                           of” some “social ecological model level” and every “social
social        information An information content entity which is a               ecological model level” is a part of some “social ecological
ecological    content      component of social ecological model which
model         entity       represents various personal or environmental          model”. Since this work focusses only on individual level, all
level                      variables that influence individuals and are          13 variables are a “part of” some “social ecological model
                           grouped together based on some common                 individual level”. All PCORnet CDM variables are a “part
                           characteristic.
social        social       A social ecological model level which
                                                                                 of” some “PCORnet CDM database”. These class
ecological    ecological   represents the personal variables influencing an      descriptions were necessary to answer the six competency
model         model level individual, specifically containing all the            questions.
individual                 variables related to the individual's attributes,
                                                                                    An example of a representation of “age range variable” is
level                      including age, gender, race, ethnicity, education,
                           income, employment, co-morbid conditions,             given in Fig. 5. Eight of 13 variables were modeled in the
                           presence of health insurance, tobacco use and         same way by relating the variable with cancer and Homo
                           year of diagnosis.                                    sapiens. Every variable is a data item conveying information
social        social       A social ecological model level which
ecological    ecological   represents the social variables influencing an        about some other entity and can be mapped with its
model         model level individual or a population, specifically               corresponding data (instances) from database. In Fig,5, “age
interperso                 containing variables related to individual's          range variable” is a data item which conveys information
nal level                  relationship with family, friends, healthcare
                           providers, community health workers or patient
                                                                                 about the quality “age” which “inheres in” human being.
                           navigators who can influence individual's             Every SE variable is represented by a level in SEM. In our
                           behavior or attitude.                                 example, “age range variable” is represented by “social
social        social       A social ecological model level which                 ecological model individual level” which is a part of “social
ecological    ecological   represents the social variables influencing an
model         model level individual or a population, specifically               ecological model”. Hence, all SE variables which are a part
organizati                 containing variables related to the availability of   of some level, all levels which are a part of SEM and the SEM
onal level                 health care, including the number of primary          are information content entities in IAO. One could draw
                           care physicians and health facilities available in
                           the individual's area of residence.                   parallels between the structure of SEM in OCRSEV and the
social        social       A social ecological model level which                 class “document” in IAO. Just as “variable” is a part of
ecological    ecological   represents the social variables influencing an        “social ecological model level” which is a part of “social
model         model level individual or a population, specifically
communit                   containing all the variables related to the
                                                                                 ecological model” in OCRSEV, “acknowledgements
y level                    individual's area of residence, including area-       section” is a part of “document part” which is a part of
                           level poverty, rural residency, area-level            “document” in IAO.
                           smoking and alcohol consumption rate and area-
                           level hospital utilization rate.



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                                                                                               Ontology of cancer related social-ecological variables



                                                                                   3 RESULTS
                                                                                      A total of 25 classes were created of which 13 classes
                                                                                   represent nine SE variables, five represent the five levels of
                                                                                   SEM, three were created for SEM hierarchy and one each for
                                                                                   PCORnet CDM specification, PCORnet CDM database,
                                                                                   cancer comorbidity and body mass. A total of 30 class
                                                                                   restrictions were created. The imported ontologies, classes
                                                                                   and relations, created classes and class restrictions helped in
                                                                                   not only answering all six competency questions but also in
                                                                                   representing models of the 13 variables. The results were
                                                                                   validated by running the DL queries as explained in the
                                                                                   methods section. The actual results exactly matched with the
                                                                                   expected results.

                     Fig. 5. RDF model for “age range variable”                    4 DISCUSSION
The ontology was validated using Description Logic (DL)                               OCRSEV is an open-ended ontology that can be extended
queries in Protégé 5.1. The DL queries along with the                              with additional variables in SEM. The principles of
expected results are shown in Table 2.                                             classification, “disjointness” and “consistent differentia” are
Competency              Description Logic        Expected Results                  followed for all the created classes. This project precludes
Questions               Query
                                                                                   the principle of “exhaustiveness” as it can include any
What are some           disease and cancer       All 5 types of cancer (breast,
diseases that are                                colorectal, lung, prostate and    number of variables in each level of the SEM. This project is
cancer?                                          cervical) and its related         limited to only some key SE variables of cancer and LSCD,
                                                 cancer types                      only five types of cancer and only one multi-level model.
What are some           (‘part of’ some          ‘socio ecological model
levels of SEM?          ‘social ecological       individual level’                 This work is a preliminary step in providing for data
                        model’) and ‘social      ‘socio ecological model           integration tasks which will in turn aid in multilevel analysis
                        ecological model         interpersonal level’              of SE predictors. Future work will involve creating models
                        level’                   ‘socio ecological model
                                                 organizational level’
                                                                                   for SE variables of all five levels of SEM and adding those
                                                 ‘socio ecological model           models to the ontology. The aboutness of the variables will
                                                 community level’                  also be explained with regards to specifying their level in
                                                 ‘socio ecological model           SEM as part of future work. Different databases for all the
                                                 policy level’
What variables are      ‘information content     All 13 variables along with all   variables will be identified and respective fields will be
represented by          entity’ and (‘part of’   of their subclasses               mapped with the classes in OCRSEV. These mappings will
SEM?                    some ‘social                                               be created using an add-on tool for Protégé 5.1 called Ontop
                        ecological model
                        level’)                                                    (Calvanese et al., 2016).
What variables are      ‘information content     All 13 variables along with
represented by          entity’ and (‘part of’   each of their subclasses          REFERENCES
SEM at the              some ‘social             (as this ontology is
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