A Responsive Web Application for the Improvement of Healthy
Habits in the Child Population
José Alberto Benítez-Andrades
1a
, Marta Martínez-Martínez
2b
, Isaías García-Rodríguez
3c
,
Carmen Benavides
1d
, Carlos Fernández-San-Juan
2e
and Pilar Marqués-Sánchez
4f
1
SALBIS Research Group, Department of Electric, Systems and Automatics Engineering, University of León,
Campus of Vegazana s/n, León, 24071, León, Spain
2
University of León, Campus of Vegazana s/n, León, 24071, León, Spain
3
SECOMUCI Research Group, Escuela de Ingenierías Industrial e Informática, Universidad de León,
Campus de Vegazana s/n, C.P. 24071 León, Spain
4
Faculty Health of Science, SALBIS Research Group, University of León, Spain
cferns08@estudiantes.unileon.es, pilar.marques@unileon.es
Keywords: e-Health, Healthy Habits, Obesity Prevention, Web Application, Web-based Application.
Abstract: The World Health Organization declared childhood obesity as a global epidemic, stressing the need for urgent
action in order to face this serious public-health problem. This paper presents a pilot program based on a
technological solution to improve the nutrition and physical activity habits in children. The solution is a
multiplatform application that can be accessed both from computers and mobile devices. A study of current,
similar solutions was carried out and a web application was designed and built, combining information on
healthy nutrition and physical activity habits with the functionalities of an online social network. This
application was used to carry out a pilot intervention with children from the first and second years of
Compulsory Secondary Education (CSE) at a school in Spain. After the pilot program, feedback was received
from the users, obtaining valuable information for introducing a number of improvements that will be
incorporated into a future program.
1 INTRODUCTION
In 2000, the World Health Organization (WHO)
classified obesity as an epidemic. Its study has been
approached from the different branches of Health
Sciences, through Psychology, and even Economics.
Within the context of governance, bodies such as
Ministries, Regional Councils, City Councils,
Healthcare Management, schools, etc., have also
shown their concern and interest in the fight against
obesity in the face of truly alarming and rising figures
(Arias, 2017). In this sense, the experts point out that
such a multicausal disease cannot be tackled from the
most traditional solutions, forgetting the relational
a
https://orcid.org/0000-0002-4450-349X
b
https://orcid.org/0000-0002-8206-378X
c
https://orcid.org/0000-0001-5209-8773
d
https://orcid.org/0000-0002-6514-6858
e
https://orcid.org/0000-0002-7384-1092
f
https://orcid.org/0000-0002-1304-1552
and contextual aspects. Valente et al speak of
relational inheritance when they explain the
transmission of diseases through peer influence. From
this perspective, programs against or to prevent
obesity should be approached in light of such
relational environments and peer influence (Valente,
2012). However, programs for the prevention of
obesity are not being considered, and there is some
disappointment with the results of current strategies,
which is why this research team considers the
implementation of this project relevant.
The WHO is working on different lines of action
aimed at obesity and infant/youth malnutrition. It
presents important experiences as follows: (i) the
Benítez-Andrades, J., Martínez-Martínez, M., García-Rodríguez, I., Benavides, C., Fernández-San-Juan, C. and Marqués-Sánchez, P.
A Responsive Web Application for the Improvement of Healthy Habits in the Child Population.
DOI: 10.5220/0008893503210328
In Proceedings of the 13th International Joint Conference on Biomedical Engineer ing Systems and Technologies (BIOSTEC 2020) - Volume 5: HEALTHINF, pages 321-328
ISBN: 978-989-758-398-8; ISSN: 2184-4305
Copyright
c
2022 by SCITEPRESS Science and Technology Publications, Lda. All rights reserved
321
Shape up Project (2006) which is based on a
collaborative approach between the individual, the
school, the community, the family, municipalities and
the whole social environment (Simovska, 2008), (ii)
School for Health in Europe (SHE), the network of
Schools for Health in Europe, which supports
organisations and professionals to develop and
support school health promotion in each country by
providing the European platform for school health
promotion (Europe Network Foundation, 2019), (iii)
the Childhood Obesity Surveillance Initiative
(COSI), which aims to measure trends in overweight
and obesity in children aged 6-9 to monitor progress
and reverse the epidemic and allow comparisons to be
made between countries in the European Region
(Wijnhoven et al., 2015), and (iv) Building resilience:
a key pillar of Health 2020 and the Sustainable
Development Goals Examples from the WHO Small
Countries Initiative (2017), a document that sets out
Health 2020's defence of resilience as a key factor in
the prevention and promotion of the health and well-
being of the individual and the community (World
Health Organization, 2017).
Recently, reports from the European Commission
(Wijnhoven et al., 2015; World Health Organization,
2017), have reflected some alarming data regarding
the indicators of obesity and overweight in Spain. In
2001, 12.6% of the adult population suffered from
obesity, rising to 16.2% in 2014, an upward trend in
both overweight and obesity. In the adolescent stage,
the prevalence of overweight and obesity at age 15
increased from 16% in 2001-2002 to 20% in 2013-
2014, while in the rest of the EU they remained at
18%. The prevalence was higher for boys than for
girls, at 24% and 15% respectively. These figures,
which will lead to an increase in the number of obese
adults, will give rise to different systemic effects of
all kinds, including cardiovascular, respiratory and
traumatological pathologies, as well as an increase in
suffering from different types of cancer in adult life
(Ortega et al, 2016; C. Yang et al., 2019). The
increase in the prevalence of overweight and obesity
in adolescents could potentially put at greater risk the
sustainability of the Spanish public health system,
which has made a major effort in prevention and
health promotion that has not come up with the
expected results. In fact, in 2011, the Spanish
Government (European Observatory on Health
Systems and Policies, 2017), aware of these figures,
adopted several legal reforms specifically to reduce
excess weight among children. For example, the
objective of the Law on Food Safety and Nutrition has
been to limit, among other things, the intakes of
saturated fats, salt and sugars in school canteens.
Doing a review of the literature in relation to the
effectiveness of the applications against the
prevention of obesity, there are different programs in
which using web or mobile applications, have
managed to reduce the percentage of fat in different
patients as well as sustaining this weight loss over
time (Coughlin et al., 2015; Mangieri, Johnson,
Sweeney, Choi, & Wood, 2019; H. J. Yang et al.,
2017). There are also studies that have been able to
verify the relationship between the use of social
networks and the effect that this has on physical
activity in the population (Godino et al., 2016;
Pinkerton, Tobin, Querfurth, Pena, & Wilson, 2017;
Zhang, Brackbill, Yang, & Centola, 2015), together
with the influence that friendships can have on greater
physical activity (Salway, Sebire, Solomon-Moore,
Thompson, & Jago, 2018).
This study presents a tool to assist in the
prevention of juvenile obesity. This tool consists of a
web application made with a responsive design.
Thanks to this responsive design, it is possible to
visualize it correctly on computers, mobile devices
and tablets. Through this application, the individual
will be able to create a profile with his or her data, on
the basis of which he/she will obtain a series of
recommendations and advice related to the
improvement of totally individualized nutritional and
sports habits, thanks to the use of artificial
intelligence algorithms and semantic technologies.
To achieve this, it is essential that the person shows
motivation and adherence to these recommendations.
The user will be able to contact people who have a
very similar profile, creating a relationship of mutual
support between both individuals. It will also have a
section for direct contact with health professionals
and researchers if necessary, as well as forums and
open communities that encourage self-monitoring
and self-motivation among the users of the
application.
2 METHODS
The tool to be developed had to be well visualized in
computers and mobile devices to involve the
participation of students of 1st and 2nd year of
Compulsory Secondary Education (CSE), between 12
and 15 years old. For this reason, it was decided to
create a web application with a responsive design. In
this way, users could make use of it in computers and
mobile devices such as tablets or mobile phones.
This web application has a social network part in
which are shown a series of tips on nutrition and
physical activity to encourage and educate users in a
HEALTHINF 2020 - 13th International Conference on Health Informatics
322
fun way. This application should have a reward
system to help promote the use of the application
among students. This web application has been
named SanoYFeliz (Happy and Healthy).
As a web application, the problem was
addressed using the perspective recommended by the
software engineering. In this sense, it was necessary
to consider the work as a software development
project and to organize the processes and tasks
according to the different phases of its life cycle.
Once the general objectives of the project had been
established, it was time for studies and analyses prior
to its implementation, subsequent decision-making
regarding the methodology and the technologies to be
used, project planning and documentation of the
system requirements.
2.1 Domain of Study
The first step carried out was an in-depth analysis of
the domain, i.e. the field of application, as well as the
context of the project. This knowledge is fundamental
for: an optimal refinement of the requirements; a
correct understanding in the communication with the
client (in this case, the research group); a correct use
of the terminology; the extraction of implicit
functionalities inherent to that domain; and finally, to
simplify the logic of the application under
development.
The nature of the project and the end user to
whom this application is addressed were decisive
aspects. Among the interests of the research project is
the collection of data for analysis. In addition, the
research group has numerous experts in nutrition,
biomedical and health sciences, etc. whose
involvement in the development process has been
very useful.
The users for whom the web application is
intended are secondary school students, which must
be taken into account when designing the interface
and the limitations and risks that this could entail due
to their age or personal circumstances: restriction on
image uploads, prevention of the use of bad words
and control over the content sent by users so that it
does not contain adult content..
Some studying in the field of health was
necessary to understand the interest of the data that
would be handled in the application. An investigation
of the most popular social network platforms was also
carried out in search of similarities with the objectives
pursued in this project. In this way, useful aspects and
7
https://www.fatsecret.com/
8
https://www.facebook.com/
ideas regarding design or functionality were found
that could be adapted and incorporated according to
one's own needs.
The social network most analyzed for its
closeness to the subject matter discussed is
FatSecret
7
, a platform that allows the user to keep a
comprehensive record of their diet and physical
activity day by day, in addition to social interaction
through community functions. The latter is the most
interesting part, as the FatSecret health section is
specifically geared towards counting calories, being
more useful, for example, for a professional audience
in the world of sport than for an average user looking
to improve their habits and lose weight.
Facebook
8
is another case study of special
interest, both for its social structure and for its event
function that serves as inspiration for event
management in this project.
As indicated in some lines of research, there are
multiple applications that make nutritional
recommendations to athletes or people who need to
eat a very specific and careful diet (Charles, Stanley,
& Agbaeze, 2013; Donciu, Ioniţǎ, Dascǎlu, &
Trǎuşan-Matu, 2012). However, no app has been
created that pursues the improvement in health and
the prevention of obesity in the juvenile public.
The aforementioned applications do not exploit
the relationships between users through the creation
of communities (Jane, Hagger, Foster, Ho, & Pal,
2018). Friends and peers have a great social impact
on the development of certain health habits (Salvy, de
la Haye, Bowker, & Hermans, 2012), especially in
this age group. Furthermore, there may be a positive
contagion effect. This means that if a person has
friends with good habits, they can improve their own
(Salathé, Vu, Khandelwal, & Hunter, 2013).
Therefore, taking advantage of the social
environment to achieve a better adherence to healthy
habits is one of the strategies to follow in this project.
What users value most about an application to
monitor their physical activity is that it makes it
entertaining and rewarding, giving them the
motivation to achieve their goals (Dharia et al., 2016).
The current applications have generic routines
without considering the preferences and the fitness
status of the adolescent, which can be
counterproductive (Dennison, Morrison, Conway, &
Yardley, 2013). The focus of this project is based on
the positive coaching method (Jones, Woods, &
Guillaume, 2016) to encourage the involvement of
the adolescent in the management of their own
A Responsive Web Application for the Improvement of Healthy Habits in the Child Population
323
healthy habits making them aware of their health and
enhancing their capacity for self-evaluation and
resilience.
2.2 Technologies Selected
The web technologies used to meet the objectives
were mainly HTML5, CSS and javascript for the
visual part and PHP and MySQL for the application
functionality.
It was necessary to design and implement the
application in a solid framework. PHP language was
used to make this application and, in particular, the
Laravel framework due to the positive references it
had, as well as its architecture based on the Model-
View-Controller (MVC) pattern, as explained in
detail in the corresponding section of this document.
On the other hand, the Bootstrap design library
was incorporated to simplify the graphic section of
the web, at the same time facilitating the coherence
between the pages, the requirement of the adaptability
of the design and the adhesion to the principles of web
usability.
2.3 Architecture
The web application was developed making use of a
Model-View-Controller (MVC) software architecture
pattern. The traditional functioning of the MVC
architecture is described in the following figure and
each of the three parts into which it divides the
application is explained below. Laravel is a PHP
framework based on MVC that facilitates the
development of applications in this language through
multiple features (Saunier, 2014).
2.4 Database Design
This project uses a relational database for data
persistence, managed with MySQL. This has been
designed based on the aforementioned specified
requirements and the study of the domain through
iterative increments throughout the development
process.
Figure 1 details the schema of the database
structure, followed by a brief explanation of each
table and field. Two fields present in most of the
tables have been omitted: the timestamps created_at
and updated_at that record, respectively, the time of
creation and the time of the last modification of each
entry in the table.
Figure 1: Database structure schema of application
SanoYFeliz.
2.5 User Interface Design
In order to comply with the user interface
requirements, some styles have been defined to
follow in the development of the application’s
visuals. The Bootstrap library was used to make the
interface visually appealing to the user and the
responsive design. Furthermore, it was decided to use
web usability principles (W3C, 2009) as follows.
Give special importance to the composition
of visual elements and the use of color.
Always look for a simple and intuitive
interface.
Focus the design on user interaction and take
into account the profile of those who will use
the application (teenagers).
2.6 Functionalities
This application has a public part, accessible to
everyone, and a private part, the social network.
In the public part, there is a home page, a section
indicating the information of the project, a section of
advice on healthy habits in the field of nutrition and
in the field of physical activity and a news section,
blog, with articles on healthy habits.
In reference to the social network part, users
should be able to: add comments on their wall, add
friends, comment on their friends' walls, reply
comments, give "like" to posts, as well as create
events and attend them. They also had to be able to
send photos and videos to administrators to access a
contest.
HEALTHINF 2020 - 13th International Conference on Health Informatics
324
Figure 2: Screenshot of three different sections of application with responsive design.
As high school students, an automatic bad word
detection system was created that removed comments
and alerted administrators that a user had made an
inappropriate comment.
On the other hand, the application had to have an
administrator role. This role allowed the following
actions: create new schools in the application, add
new nutrition and physical activity tips, add new news
to the blog, monitor events, and review and moderate
user comments.
2.7 Specification of the Reward System
The aim of this rewards system is to recognize users
when they carry out positive activities on the
platform, both from a social and a health perspective.
In this way they are more motivated to continue
progressing at the same time as having fun.
The reward mechanisms are designed to be
attractive to teenage students, based on a system of
healthy points. The healthy points are called
"BieneSTARS" (in English it could be called Well-
beingSTARS), a simple word game that combines
with its graphic representation as a star icon. Each
user has a counter that accumulates BieneSTARS,
and depending on the total amount is assigned a level
to be more stimulating. The following image, figure
3, shows how the user is informed of his progress so
far, including a bar that is completed as they approach
the next level.
The users start from level 0 and when they get 10
points they reach level 1. The BieneSTARS necessary
Figure 3: Screenshot of application showing BieneSTARS
wall section (A) an in an user profile (B).
to raise the level are increased by 10 at each level. In
order to reach level 4, a total of 100 will have to be
accumulated. No limit has yet been set for the level
that can be reached, although it is difficult to reach
high figures taking into account the
BieneSTARS/level curve represented in the
following graph, figure 4.
This reward system takes into account the
following actions: making friends, attending an event,
creating a new event, participating in the contest,
reading a blog post, updating body measurements.
A Responsive Web Application for the Improvement of Healthy Habits in the Child Population
325
Figure 4: Ratio of points (BieneSTARS)/level in the reward
system.
3 RESULTS
The SanoYFeliz platform (https://www.sanoyfeliz.es)
is operational and includes all the functionalities
described in this document.
The following sections review the main problems
encountered during the development of the
application, document the pilot experience of testing
the application with real users and list various
improvements and additions that are planned to be
added to the web application from now on.
3.1 Experience with Real Users
In March 2019 a pilot project was launched to test the
platform with students from the Diocesan School San
Ignacio de Ponferrada, León. The research group, in
charge of the contacts with the educational centre and
the almost 90 participating students, wanted to check
the acceptance of the web application by these users,
as well as finding out possible errors, changes and
improvements. The study sample consisted in
students from two courses, not only overweight or
obese ones were selected.
The students were first guided through the
registration process and invited to fill in their body
measurements and healthy habits questionnaires,
giving them the freedom to use the social functions of
applications from then on. Everything went
satisfactorily and the small errors detected were
corrected quickly and without prejudice to users or
the system.
During the first days, the client became aware of
the need to include new administration functions for
greater control and supervision of the students, in the
face of possible behaviours that had not been foreseen.
Modifications such as the inclusion of private events
were also proposed. All of this was gradually
incorporated into the platform (as detailed in the
section on planning) without the need to introduce
periods of inactivity for maintenance, as there was a
replica of the system on which to implement the
changes and carry out the corresponding tests.
New questionnaires were added later, important
data sources for customer investigations. At the
beginning of May, the students were asked to fill in a
final "satisfaction questionnaire" to collect their
impressions and assessments of the web application.
Figure 5: Screenshot of SanoYFeliz showing the public interface and the menu.
HEALTHINF 2020 - 13th International Conference on Health Informatics
326
The response was generally positive and useful
suggestions were extracted for further expansion of
the system, as discussed in the following section.
This pilot experience was also very satisfactory
for the client, who obtained numerous data of interest
for their analysis. It is planned to extend the use of the
application to several schools in the province of León
in the near future.
3.2 Extensions for Further
Development
Based on the recent pilot experience, new needs arose
that are translated into functionalities to be added to
the web application before its implementation in new
educational centres. Thus, the development of the
product will continue with the launch of new finished
versions.
Among the possible new tasks are the following:
Implement a system of private messages
between users.
Improve the reward system with a weekly
ranking with the users who have obtained
more BieneSTARS (healthy points).
Automatic sending of emails to inactive users
for a certain period of time, encouraging them
to use the application.
In the moderation of publications, add filters
to facilitate the work of the administrator.
Allow the user to configure the notifications
they receive.
In publications, implement mentions to users.
Add to the news blog a system of tags that
allows the administrator to tag the news and
the users to navigate through them.
Give more visibility to the "I like" by
including in the user profile a tab with the
publications he liked and allowing each
publication to say which users belong to the "I
like" he has received.
Furthermore, certain future lines of expansion,
within the framework of this research project, are
contemplated, such as the improvement of artificial
intelligence techniques to the individualized
recommendations of the system through semantic
web technologies, developing a knowledge model
with OWL ontologies and a reasoning module.
4 CONCLUSIONS
This final section presents the conclusions after the
completion of the project tasks and discusses the
degree of success of the work carried out, using as
acceptance criteria the achievement of the objectives,
compliance with software requirements and customer
satisfaction. Based on this, the following conclusions
can be highlighted:
The web application developed may be useful
for its purposes: support and motivation to the
adolescent student for the acquisition of
healthy routines, and exploitation of the data
obtained for the research project.
All the components and functionalities
required and with the expected behaviour have
been implemented.
The specified functional and non-functional
requirements are implemented in a verifiable
manner.
The agile methodology adopted has allowed
the planning to be carried out successfully.
The pilot experience of testing the application
with real users has been satisfactory both for
the client and for the users themselves.
It has been possible to obtain a final product
according to the expectations and needs of the
client
ACKNOWLEDGEMENTS
The work presented in this paper was supported by
Junta de Castilla y León [grant number LE014G18].
REFERENCES
Arias, N. (2017). Las administraciones públicas como
soporte en la prevención contra la obesidad juvenil:
estudio de factores relacionales y análisis de redes
sociales. 314.
Charles, E., Stanley, D., & Agbaeze, E. (2013).
Knowledge-Based Diet and Physical Exercise Advisory
System. International Journal of Science and Research
(IJSR) ISSN (Online Index Copernicus Value Impact
Factor, 14(7), 2319–7064. Retrieved from
http://www.ijsr.net/archive/v4i7/SUB156493.pdf
Coughlin, S. S., Whitehead, M., Sheats, J. Q.,
Mastromonico, J., Hardy, D., & Smith, S. A. (2015).
Smartphone Applications for Promoting Healthy Diet
and Nutrition: A Literature Review. Jacobs Journal of
Food and Nutrition, 2(3), 021. Retrieved from
http://www.ncbi.nlm.nih.gov/pubmed/26819969
Dennison, L., Morrison, L., Conway, G., & Yardley, L.
(2013). Opportunities and challenges for smartphone
applications in supporting health behavior change:
Qualitative study. Journal of Medical Internet
Research, 15(4). https://doi.org/10.2196/jmir.2583
A Responsive Web Application for the Improvement of Healthy Habits in the Child Population
327
Dharia, S., Jain, V., Patel, J., Vora, J., Chawla, S., &
Eirinaki, M. (2016). PRO-Fit: A personalized fitness
assistant framework. Proceedings of the International
Conference on Software Engineering and Knowledge
Engineering, SEKE, 2016-January, 386–389.
https://doi.org/10.18293/SEKE2016-174
Donciu, M., Ioniţǎ, M., Dascǎlu, M., & Trǎuşan-Matu, Ş.
(2012). The runner - Recommender system of workout
and nutrition for runners. Proceedings - 13th
International Symposium on Symbolic and Numeric
Algorithms for Scientific Computing, SYNASC 2011,
230–238. https://doi.org/10.1109/SYNASC.2011.18
Europe Network Foundation. (2019). Schools for Health in
Europe (SHE).
European Observatory on Health Systems and Policies.
(2017). Estado de Salud en la Union Europea, Perfil
sanitario de España 2017. https://doi.org/10.1016/
S1359-6454(99)00194-9
Godino, J. G., Merchant, G., Norman, G. J., Donohue, M.
C., Marshall, S. J., Fowler, J. H., … Patrick, K. (2016).
Using social and mobile tools for weight loss in
overweight and obese young adults (Project SMART):
a 2 year, parallel-group, randomised, controlled trial.
The Lancet Diabetes and Endocrinology.
https://doi.org/10.1016/S2213-8587(16)30105-X
Jane, M., Hagger, M., Foster, J., Ho, S., & Pal, S. (2018).
Social media for health promotion and weight
management: A critical debate. BMC Public Health.
https://doi.org/10.1186/s12889-018-5837-3
Jones, R. J., Woods, S. A., & Guillaume, Y. R. F. (2016).
The effectiveness of workplace coaching: A meta-
analysis of learning and performance outcomes from
coaching. Journal of Occupational and Organizational
Psychology, 89(2), 249–277. https://doi.org/10.1111/
joop.12119
Mangieri, C. W., Johnson, R. J., Sweeney, L. B., Choi, Y.
U., & Wood, J. C. (2019). Mobile health applications
enhance weight loss efficacy following bariatric
surgery. Obesity Research & Clinical Practice, 13(2),
176–179. https://doi.org/10.1016/J.ORCP.2019.01.004
Ortega et al. (2016). Obesity, Diabetes, and Cardiovascular
Diseases Compendium. Obesity and Cardiovascular
Disease, 1752–1770. https://doi.org/10.1161/
CIRCRESAHA.115.306883
Pinkerton, S., Tobin, J. L., Querfurth, S. C., Pena, I. M., &
Wilson, K. S. (2017). “Those sweet, sweet likes”:
Sharing physical activity over social network sites.
Computers in Human Behavior, 69, 128–135.
https://doi.org/10.1016/J.CHB.2016.12.028
Salathé, M., Vu, D. Q., Khandelwal, S., & Hunter, D. R.
(2013). The dynamics of health behavior sentiments on
a large online social network. EPJ Data Science, 2(1),
1–12. https://doi.org/10.1140/epjds16
Salvy, S.-J., de la Haye, K., Bowker, J. C., & Hermans, R.
C. J. (2012). Influence of peers and friends on
children’s and adolescents’ eating and activity
behaviors. Physiology & Behavior, 106(3), 369–378.
https://doi.org/10.1016/j.physbeh.2012.03.022
Salway, R. E., Sebire, S. J., Solomon-Moore, E.,
Thompson, J. L., & Jago, R. (2018). Associations
within school-based same-sex friendship networks of
children’s physical activity and sedentary behaviours: a
cross-sectional social network analysis. International
Journal of Behavioral Nutrition and Physical Activity,
15(1), 18. https://doi.org/10.1186/s12966-018-0653-9
Saunier, R. (2014). Getting Started with Laravel 4. Packt
Publishing.
Simovska, V. (2008). Participation, action, and school-
community collaboration: Case study of school-based
health promotion to influence determinants of
childhood obesity - Maastricht. Retrieved from
http://pure.au.dk/portal/files/260/Case_study_research
__Maastricht
Valente, T. W. (2012, July 6). Network interventions.
Science, Vol. 336, pp. 49–53.
https://doi.org/10.1126/science.1217330
W3C. (2009). Method of presenting a web page for
accessibility browsing. Retrieved from
https://patents.google.com/patent/US9489131B2/en
Wijnhoven, T. M. A., Van Raaij, J. M. A., Yngve, A.,
Sjöberg, A., Kunešová, M., Duleva, V., … Breda, J.
(2015). WHO European childhood obesity surveillance
initiative: Health-risk behaviours on nutrition and
physical activity in 6-9-year-old schoolchildren. Public
Health Nutrition, 18(17), 3108–3124.
https://doi.org/10.1017/S1368980015001937
World Health Organization. (2017). Building resilience: a
key pillar of Health 2020 and the Sustainable
Development Goals - Examples from the WHO Small
Countries Initiative. In World Health Organization.
Retrieved from http://www.euro.who.int/en/
publications/abstracts/building-resilience-a-key-pillar-
of-health-2020-and-the-sustainable-development-
goals-examples-from-the-who-small-countries-
initiative-2017
Yang, C., Lu, Y., Xia, H., Liu, H., Pan, D., Yang, X., &
Sun, G. (2019). Excess Body Weight and the Risk of
Liver Cancer: Systematic Review and a Meta-Analysis
of Cohort Studies. Nutrition and Cancer, 1–13.
https://doi.org/10.1080/01635581.2019.1664602
Yang, H. J., Kang, J. H., Kim, O. H., Choi, M., Oh, M.,
Nam, J., & Sung, E. (2017). Interventions for
preventing childhood obesity with smartphones and
wearable device: A protocol for a non-randomized
controlled trial. International Journal of Environmental
Research and Public Health, 14(2).
https://doi.org/10.3390/ijerph14020184
Zhang, J., Brackbill, D., Yang, S., & Centola, D. (2015).
Efficacy and causal mechanism of an online social
media intervention to increase physical activity: Results
of a randomized controlled trial. Preventive Medicine
Reports. https://doi.org/10.1016/j.pmedr.2015.08.005
HEALTHINF 2020 - 13th International Conference on Health Informatics
328