NUDGE - NUtritional, Digital Games in Enable Hanna Schäfer David A. Plecher Sophie L. Holzmann hanna.schaefer@tum.de plecher@in.tum.de sophie.holzmann@tum.de Georg Groh Gudrun Klinker Christina Holzapfel grohg@in.tum.de klinker@in.tum.de christina.holzapfel@tum.de Hans Hauner Technical University of hans.hauner@tum.de Munich Germany Figure 1. Teaser figure of the NUDGE platform. Left: Central avatar element and the nutritional feedback screen. Middle: Motivational nudges and social cooking events. Right: Preview of the serious game prototype "Fit, Food, Fun". ABSTRACT Author Keywords The digital games platform NUDGE (NUtritional, Digital Nutrition; Health; Adolescents; Gamification; Serious Games; Games in Enable) is one of the digital nutritional commu- Persuasion; Personalization; enable-Cluster; nication systems within the nutrition research cluster enable. NUDGE aims at changing the nutritional behavior of adoles- cents using different levels of persuasion. The central platform INTRODUCTION element is a personalized avatar representing the user’s nutri- Overweight and obesity, especially in the younger population, tion and game status as playful feedback. Additionally, real are major health concerns worldwide (WHO, [34]). Accord- world interactions are integrated using tailored nudges, social ing to a European statistic more than 60% of children that are connections, and real life challenges. Finally, different serious affected by overweight before puberty will maintain weight in games, e.g. the "Fit, Food, Fun" prototype, are used to increase young adulthood (WHO, [33]). the user’s knowledge and capabilities regarding nutrition. The The interdisciplinary enable-cluster is one of four clusters NUDGE platform is going to be evaluated in a pilot study in about nutrition research funded by the German Federal Min- spring 2018. istry of Education and Research (BMBF) [14]. In one of its core projects, enable investigates digital communication strate- gies to improve nutrition behavior. As a result, the NUDGE system is designed as an educative and preventive tool for ado- lescents to impart nutritional knowledge in a playful and moti- vational setting. To reach this goal, it promotes health-related outcomes using serious games [1] and different persuasive elements [27]. Besides the imparting of nutritional knowledge, NUDGE tries to accompany its users by creating positive feedback loops using both automated and real world input to ensure the users Positive Gaming: Workshop on Gamification and Games for Wellbeing A CHI PLAY ’17 Workshop, October 15, 2017, The Netherlands c 2017 Copyright held by the feel comfortable with their behavioral changes. authors/owners. PREVIOUS WORK ON HEALTH GAMES be to give the user achievements, when he fills his nutritional There have been several studies on different types of games diary. A serious game however would incorporate the nutri- for health and fitness. [3] reviewed 25 video games and found tional knowledge and offer activities, that will transfer that that they were split into different outcomes such as knowledge knowledge actively to the user. At the same time the gaming increase and changes in attitude and behavior. Since NUDGE character is stimulating the user’s intrinsic motivation to play wants to encompass a holistic approach the following six well and to learn [36]. The primary purpose of a serious game is cited serious games were reviewed regarding their persuasive to transfer knowledge in a playful gaming context [11]. The strategies and health-related goals. NUDGE platform uses the concepts of serious gaming and One of the first digital nutritional games, ’Packy & Marlon’, motivational stimulation in different nutritional mini-games. was designed for children and adolescents with diabetes [8]. The playing children had to manage the blood glucose levels Persuasive Gaming of two elephants with diabetes by choosing adequate food and Persuasive strategies are application components that are de- insulin quantities. A six-month randomized controlled trial signed to influence the user’s behavior or attitude towards a (n=59; age=8-16 years) showed that after playing the user’s predefined goal [16]. [27] defined a framework with 28 differ- knowledge about diabetes increased, while the amount of ur- ent persuasive strategies. [35] reviewed the implementation of gent hospital visits decreased. those different strategies in 44 papers from different domains. The game ’HungryRedPlanet’ [2] (age=10-15 years) used For the health domain, they came up with the following ten a similar approach for healthy adolescents by utilizing the most used strategies: feedback, self-monitoring, suggestion, USDA (U.S. Department of Agriculture) Pyramid Guide for social role, simulation, tailoring, tunneling, reminders, reduc- a healthy and balanced nutrition. Similar to the game ’Packy tion, and reward. & Marlon’, the goal of this game is to manage adequate food There are drawbacks to some of these strategies regarding their quantities to win the game and stop earths starvation. applicability to all user groups. Some strategies only work for The two serious games ’Escape from Diab’ (2010) [32] specific selection of personality types. [28] and [20] describe (age=10-12 years) and ’PLAY, MATE!’ (2010) [4] (n=180; how using generic persuasive strategies might even reverse the age=9-12 years) focused on persuasion and behavior change motivational effect for specific personality types. However, in addition to the knowledge transfer. The study of [4] showed strategies such as competition, comparison, self-monitoring that games and persuasive elements could increase the physi- and suggestion seem to be effective on most personality types cal activity without disturbing the enjoyment of players. [30]. The NUDGE platform uses the concepts of feedback, More health games are starting to integrate different persuasive self-monitoring, social role, simulation, tailoring, reminders, concepts to address different target groups. For example, the rewards and personalization. National Mindless Eating Challenge (NMEC) [19] (n=2053; age=39,8 years in average) integrated comparisons, customiza- Positive Gaming tion, rewards, personalization and suggestions. Finally, the The concept of positive computing was defined by Calvo game ’Move2Play’ [5] (n=12; age=12-13 years) provides a and Peters (2014) [9] and includes three different design ap- setup for physical activity similar to the one NUDGE is im- proaches. The preventative design methodology excludes any plementing for nutrition. They integrated monitoring, goal- negative influence of the systems towards the user, while the setting, a social component, achievements, rewards, and an active design methodology tries to integrate elements, that avatar component. Their small study showed, that the chil- specifically use positive influence on the user. Finally, the dren were able to understand all different components of the dedicated design approach focuses on applications that have setup and enjoyed the customizing of the avatar and the social wellbeing as their primary goal. To implement those design components. strategies [9] also suggest different factors such as positive emotions, motivation, self-awareness, and empathy that can CONCEPTS OF GAMES FOR HEALTH be utilized when building positive applications. The NUDGE In addition to the games review, different theoretical ap- platform uses the concepts of preventative and active design proaches influenced the design of the NUDGE platform. The using different intra- and interpersonal factors such as social concept of serious gaming was applied to derive mini-games components and a quantified-self avatar. for nutritional knowledge and skill transfer. The theory of persuasive gaming was used to develop the interaction of the PRELIMINARY WORK platform such as the avatar and the notification system. The The target group of the NUDGE platform are adolescents concept of positive gaming was applied to furthermore im- aged from 14 to 17 years. In preparation of the nutritional prove the user’s wellbeing during his behavior change. game design a survey was conducted. The aim was to de- scribe needs, wishes and motives of German adolescents re- Serious Gaming garding nutritional and digital games, in order to design a Gamification as a preventive tool for promoting health-related target group-specific serious game fostering an improved nu- behaviors often lacks in efficacy. It mainly transfers game trition. Literature [13][15] indicates that nutrition information elements such as points or leaderboards to a non-gaming con- in adolescents is deficient and needs to be promoted. In 2010, tent [12]. In contrast to gamification, serious games offer the nutrition report of the German Nutrition Society (DGE) the possibility for an active exploration of serious intellectual revealed that only about 50% of adolescents are adequately in- problems [1]. For example, a gamification approach would formed about nutrition [13]. The questionnaire was developed through an interdisciplinary team of nutritionists and computer healthy/unhealthy behavior and thus ease negative feedback scientists. Socio-demographic and anthropometric data were given by the system, while still giving motivation through obtained as well. The 43-item questionnaire has been carried positive feedback. Finally, the avatar serves as a bus between out in the form of hard-copy and could be completed in 15 the different serious games. For example, the avatar spends to 20 minutes. In total, 339 adolescents aged from 13 to 18 energy by playing the serious mini-games to limit the screen years (46% female), participated in the survey, which has been time for the participating adolescents. While the user’s nu- conducted in six general secondary schools of the city and trition based on the dietary record affects the avatars’ body administrative district of Rosenheim between June 2016 and composition, the user’s real life physical activity measured by June 2017. The survey revealed that the nutritional knowledge Google Fit API impacts the avatar’s energy level [24]. This in German adolescents is deficient. At same time, most ado- physical activity is used to increase the avatar’s energy and lescents play digital games and desire nutrition information thus represents another real-life connection. Further avatar in digital games. Results are in line with findings of another characteristics, such as the current nutrient level will be inte- survey (2016) [15]. According to this survey two third of grated in future serious games e.g. by decreasing visibility or the 12 to 19 years old participants play digital games daily slowing movement. Besides the simulation state of the avatar or several times a week. Taken together, a serious nutritional regarding real life values such as nutrition and activity, the game seems to be a potential educative and preventive tool to avatar also shows the platform status. For example, the avatar impart nutritional knowledge in order to promote a healthy will show hunger, if the user has not updated the diary, and lifestyle in adolescents. it will be excited, if the user has not played any games in a certain time frame. This status feedback serves as a nudge SYSTEM DESIGN based on the user’s motivation through self-competition [10]. The NUDGE platform is built as a system connecting multiple intervention bricks. The core of the platform is a digital avatar. Social and Motivational Elements It represents the health state of the user based on a digital Since the NUDGE platform tries to encompass real-life behav- nutrition diary. The body composition of the avatar reflects ior change, the virtual avatar and serious games components weight gain and loss. In addition to the physically adaption, the might not be sufficient to guide the users in their transition. avatar also expresses moods such as hungry, lonely or excited. Additional persuasive and positive elements that were incorpo- These moods should motivate the user to perform specific rated are personality dependent nudges, social support groups platform actions such as filling his nutrition diary, interacting and real-life challenges. with groups, or playing serious games. The avatar can enter According to [29] 6 of the 21 reviewed persuasive games for different serious mini-games such as the game prototype "Fit, nutrition include a social support strategy. In the NUDGE plat- Food, Fun", which focuses on macro-nutrients and energy con- form, social support is given by groups of 5-10 people, that tent of food. Other platform games address physical activity share challenges, a leaderboard and access to social games, or micro-nutrient effects. Additionally, the user is motivated such as the ISS space game. In case of missing social contacts by a social network and real life challenges, such as group with similar problems, the system will recommend groups cooking events. He receives nudges about progress events and based on age, location, gender and BMI. The group system social comparisons. The following components try to include including the group size, group management and leaderboard the before mentioned persuasive or positive strategies. was evaluated in a small focus group with five participants and a usability test with five further participants was conducted Avatar as Central Platform Element as well [23]. Both evaluation methods revealed a positive Within the avatar different persuasion concepts are combined. feedback on the general approaches, while the game design First, the avatar can be adapted to the user’s appearance using and usability were still criticized. different hair, clothing and color schemes. The designs were It has been shown that tailoring nudges and personalizing specifically chosen to create an emotional connection. This achievements can strongly increase the motivational effect design should increase the caretaking motivation between the [28]. Our personality dependent nudges are based on seven users and the avatar using a schema of childlike characteristics gamer types identified by the BrainHex model [26] and the Big [17]. At the same time the avatar visualizes the nutrition status Five personality types [18]. Those types are used to select the of the user based on a dietary record. If the user eats healthy type of nudges users receive. For example, someone who is a for more than three days, the avatars bodyweight will decrease seeker in the BrainHex model, would receive praise nudges on and new clothing designs will be available. To prevent weight diary entries, physical activity or weight loss. In addition to gain from causing negative psychological effects, the body event nudges, there are achievement nudges such as playing sizes are limited to 5 stages and were carefully selected in a all games, or regularly filling the dietary diary. way that positively depicts even the heavier avatar versions. The real-life group challenges are integrated in the form of Besides this visual feedback, the user can also experiment social cooking events. This kind of challenge solves multiple with nutritional effects using a fast forward scenario. This issues of real-life challenges. First, it validates the user’s action scenario shows the nutrient contents and their implications, by the social feedback. Secondly, it offers social motivation in the given future dietary situation [25]. Both approaches for the user to win the challenge. Finally, it opens a platform utilize the self-quantification and simulation strategies of the for exchange about the received nutritional knowledge and persuasive system design. Regarding positive computing the other platform elements. These real-life group events were avatar should externalize the user’s emotions concerning his evaluated in a small user study [23] with nine participants, that conducted six different group cooking events within two waist circumferences) will be obtained. The study outcome weeks. The study showed, that young people are interested will be assessed with different validated questionnaires such in such events. The most effective motivational elements are as the User Experience Questionnaire [22] and the System Us- the leaderboard list, showing the best cooking event/host of ability Scale [7]. Additionally, a domain specific survey will each group, the motto (e.g. Blue Titanic Dinner), giving each be used to evaluate the knowledge and skill gain in nutrition. cooking event a creative aspect, and the ingredient challenges, Finally, motivational questionnaires will be used pre and post telling the host to e.g. involve salmon in his dinner. study to show any changes in the users attitude. We expected the pilot study to show how knowledge gain and behavior "Fit, Food, Fun" as a Serious Game change can be increased through persuasive and positive game The NUDGE platform combines different serious games such elements. Furthermore, we want to show that the users feel as an ISS space game or a role-play exergame. This chapter safe and motivated during their behavioral transition due to exemplary describes one of the serious game prototypes called the social and motivational platform framework. "Fit, Food, Fun" [37]. This game concentrates on improving the nutritional knowledge and on strengthening skills in using ACKNOWLEDGEMENTS that knowledge to change dietary behavior. The knowledge The preparation of this paper was supported by the enable transfer is embedded in a journey through Europe. In every cluster and is catalogued by the enable steering committee as country the user has to succeed in three minigames: enable 008 (http://enable-cluster.de). This work was funded The Card Game offers the player two different cards with a by a grant of the German Ministry for Education and Research sort of food each. The challenge is to find the card with the (BMBF) FK 01EA1409H. highest or lowest value in a certain category like carbs, fats, proteins and calories. REFERENCES In the Estimation Game the user has to guess the amount of 1. Clark C Abt. 1987. Serious games. University press of sugar or fat (displayed as cubes of sugar and drops of fat) that America. is contained in a specific type of food. 2. D Michael Anderson. 2002. Hungry Red Planet: In the Backpack Game the player must fill a backpack with Children’s multimedia nutrition simulation software. In food which should supply enough energy for a certain activity The 130th Annual Meeting of APHA. like swimming or running. Without enough energy, the player won’t make it to the finish line. Choosing too much energy 3. Tom Baranowski, Richard Buday, Debbe I Thompson, slows down the player resulting in a lower score. and Janice Baranowski. 2008. Playing for real: video The first two games impart knowledge about the nutrients games and stories for health-related behavior change. of food whereas in the third game the user learns about the American journal of preventive medicine (2008), 74–82. equivalence between physical activity and these nutrients. 4. Shlomo Berkovsky, Mac Coombe, Jill Freyne, and Dipak In addition to the link of nutritional knowledge and gaming Bhandari. 2010. Isn’t it great?: you can PLAY, MATE!. strategies, this serious game also integrates different edu- In Proceedings of the 15th international conference on cational concepts [6]. For example, the transition between Intelligent user interfaces. countries as well as the transition within the mini-games of one country were designed along the AVIVA [31] model for 5. Pavol Bielik, Michal Tomlein, Peter Krátky, Štefan teaching. Additionally, the game elements have been checked Mitrík, Michal Barla, and Mária Bieliková. 2012. against the ARCS model [21] and redefined to cover at least Move2Play: An Innovative Approach to Encouraging one of the four motivational design elements. For example, People to Be More Physically Active. In Proceedings of the different country levels were restructured into a travel the 2Nd ACM SIGHIT International Health Informatics route through Europe and complemented with information Symposium. about each region to increase the curiosity of players. 6. Alexandra Brandl. 2017. Design and Evaluation of Educational Elements in a Serious Game on Nutrition. Technical University of Munich (2017). CONCLUSION AND FUTURE WORK 7. John Brooke and others. 1996. SUS-A quick and dirty The NUDGE platform is research project in progress. It tries usability scale. Usability evaluation in industry (1996). to encompass a holistic set of persuasive and positive mea- sures into a serious game platform for health. While the major 8. Stephanie J Brown, Debra A Lieberman, BA Gemeny, design and implementation steps are concluded, each com- Yong Chan Fan, DM Wilson, and DJ Pasta. 1997. ponent still needs to be improved through small focus group Educational video game for juvenile diabetes: results of a interviews. Also, the results of the preliminary survey will be controlled trial. Medical Informatics (1997). included until the final evaluation. The final NUDGE platform 9. Rafael A Calvo and Dorian Peters. 2014. Positive is going to be evaluated in a pilot study in spring 2018. Dif- computing: technology for wellbeing and human ferent outcomes like nutrition knowledge and motivation will potential. MIT Press. be assessed using appropriate questionnaires. To compare the characteristics of participants, the Big Five types [18] and the 10. Zhi-Hong Chen, Tzu-Chao Chien, and Tak-Wai Chan. BrainHex gamer types [26] will be derived. Additionally, phe- 2011. Using Self-competition to Enhance Students’ notypic data (gender, age, body weight, body height, hip and Learning. In International Conference on Technologies for E-Learning and Digital Entertainment. Springer, 25. Carsten Mück. 2017. Motivator Avatar: Supporting 234–235. Healthy Nutrition. Technical University of Munich 11. Michael David and Chen Sande. 2006. Serious Games: (2017). Games That Educate, Train, and Inform. Course 26. Lennart E Nacke, Chris Bateman, and Regan L Mandryk. technology, Cengage learning (2006). 2014. BrainHex: A neurobiological gamer typology 12. Sebastian Deterding, Dan Dixon, Rilla Khaled, and survey. Entertainment computing (2014). Lennart Nacke. 2011. From game design elements to 27. Harri Oinas-Kukkonen and Marja Harjumaa. 2009. gamefulness: defining gamification. In Proceedings of the Persuasive systems design: Key issues, process model, 15th international academic MindTrek conference: and system features. Communications of the Association Envisioning future media environments. for Information Systems (2009). 13. DGE. 2000. Nutrition Report 2000. Henrich Druck + 28. Rita Orji, Regan L Mandryk, Julita Vassileva, and Medien GmbH. Kathrin M Gerling. 2013. Tailoring persuasive health 14. enable cluster. 2017. Enable-Cluster. games to gamer type. In Proceedings of the SIGCHI http://enable-cluster.de/. Accessed: 2017-08-11. Conference on Human Factors in Computing Systems. 15. Sabine Feierabend, Theresa Plankenhorn, and Thomas 29. Rita Orji and Karyn Moffatt. 2016. Persuasive technology Rathgeb. 2016. JIM Studie 2016, Jugend, Information, for health and wellness: State-of-the-art and emerging (Multi-) Media Basisstudie zum Medienumgang 12- bis trends. Health informatics journal (2016). 19-Jähriger in Deutschland. Medienpädagogischer 30. Rita Orji, Julita Vassileva, and Regan L Mandryk. 2014. Forschungsverbund Südwest (mpfs). Modeling the efficacy of persuasive strategies for 16. B. J. Fogg. 2002. Persuasive Technology: Using different gamer types in serious games for health. User Computers to Change What We Think and Do. Ubiquity Modeling and User-Adapted Interaction (2014). (2002). 31. Christoph Städeli. 2013. Kompetenzorientiert 17. Melanie L Glocker, Daniel D Langleben, Kosha Ruparel, unterrichten-das AVIVA-Modell: fünf Phasen guten James W Loughead, Ruben C Gur, and Norbert Sachser. Unterrichts. 2009. Baby schema in infant faces induces cuteness perception and motivation for caretaking in adults. 32. Debbe Thompson, Tom Baranowski, Richard Buday, Ethology (2009). Janice Baranowski, Victoria Thompson, Russell Jago, and Melissa Juliano Griffith. 2010. Serious video games for 18. Oliver P John, Eileen M Donahue, and Robert L Kentle. health: How behavioral science guided the development 1991. The big five inventory-versions 4a and 54. Berkeley, of a serious video game. Simulation & gaming (2010). CA: University of California, Berkeley, Institute of Personality and Social Research. 33. WHO. 2008. Health topics - Noncommunicable diseases - Obesity - Data and statistics. 19. Kirsikka Kaipainen, Collin R Payne, and Brian Wansink. http://www.euro.who.int/en/health-topics/ 2012. Mindless eating challenge: retention, weight noncommunicable-diseases/obesity/data-and-statistics. outcomes, and barriers for changes in a public web-based Accessed: 2017-08-11. healthy eating and weight loss program. Journal of medical Internet research (2012). 34. WHO. 2014. Global status report on noncommunicable diseases 2014. World Health (2014). 20. Maurits Kaptein, Boris De Ruyter, Panos Markopoulos, and Emile Aarts. 2012. Adaptive persuasive systems: a 35. Isaac Wiafe and Keiichi Nakata. 2012. Bibliographic study of tailored persuasive text messages to reduce Analysis of Persuasive Systems: Techniques; Methods snacking. ACM Transactions on Interactive Intelligent and Domains of Application. In Persuasive Technology: Systems (TiiS) (2012). Design for Health and Safety; The 7th International Conference on Persuasive Technology; Sweden; June 6-8; 21. John M Keller. 2009. Motivational design for learning Adjunct Proceedings. and performance: The ARCS model approach. 22. Bettina Laugwitz, Theo Held, and Martin Schrepp. 2008. 36. Wee Ling Wong, Cuihua Shen, Luciano Nocera, Eduardo Construction and evaluation of a user experience Carriazo, Fei Tang, Shiyamvar Bugga, Harishkumar questionnaire. In Symposium of the Austrian HCI and Narayanan, Hua Wang, and Ute Ritterfeld. 2007. Serious Usability Engineering Group. video game effectiveness. In Proceedings of the international conference on Advances in computer 23. Maximilian Alexander Mayer. 2017. Development and entertainment technology. Evaluation of Food-Recommendation-System for Groups. Technical University of Munich (2017). 37. Johannes Ziegltrum. 2017. Development of a Serious Game to support a healthy diet. Technical University of 24. Sanjay M Mishra. 2015. Google Fit API. Wearable Munich (2017). AndroidTM : Android Wear & Google Fit App Development (2015).