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  • 1. Vittles: accomplishing a healthier lifestyle Anne Everars Master Computer Science, Human-Computer Interaction Department of Computer Science, KULeuven, Belgium Email: anne.everars@student.kuleuven.be Abstract—The abstract goes here. I. INTRODUCTION Upon looking at the important risk factors that are related to illness and death in most countries, one can uncover that they arist from non-transitional diseases such as high blood pressure, high cholesterol, low consumption of fruit and vegetables, overweight and obesity, sedentary lifestyle and smoking. Except for smoking, these risks are related to nutrition and physical activities. Overconsumption of proteins, fats, carbohydrates and alcohol can cause an excess of energy that gets stacked in the body. Consequentially, a combination of lowering the energy intake (what is eaten) and raising the energy consumption (physical activities) are needed in order to obtain a healthy energy balance. [1] A. Dietary intake An important aspect of monitoring the dietary intake is the registration of what is actually eaten by the user. This registration can be done manually a user can enter what he/she ate or automatically. Here, it is important that it is easy for the user to register the dietary intake and that it does not consume too much time. [2] Self-monitoring is proven to be a critical skill for successful weight management. [3] In entering what a user eats, an important concept is that of the kCal. It is an amount that is used frequently in the context of eating and participating in activities.[4] B. Energy consumption In addition to the dietary intake, the activities of a person also relate to the amount of calories that can be consumed or that are burned. However, even while sitting idle (or sleeping) a user consumes energy. This energy consumption can be calculated according to the Harris-Benedict equation, which considers the basal metabolic rate (BMR). For men this can be calculated as: 88.362 + 13.397w + 4.799h − 5.677a (1) with w the weight in kg, h the hight in cm and a the age in years. A whole range of activities exist. And each activity burns a certain amount of energy. This amount is, for example, proportional to the level of intensity (e.g. by running you burn more calories than by walking) or the duration. [8] The importance of sports in relation to personal health and/or weight management is stressed by multiple studies [5], [6], [7], [8]. Regular exercise has been shown to help people maintain their healthy lifestyle and weight loss more easily. C. Setting goals Goal setting has been shown to be important to ones ability to control ones behaviour. [9] Setting small, reachable, but challenging goals is an important step in keeping a person mo- tivated to keep going. [5], [10], [11], [12] The road of loosing weight and maintaining a healthy lifestyle can be challenging. And some days will be easier than others. Therefore, a positive stimulant is important. Working with goals has some important issues to keep in mind however. Firstly, goals direct the attention, efforts and actions of the user towards goal-relevant actions. This can be at the expense of non-relevant (but important) actions. [11] Second, making the goals too difficult to reach, can have a negative effect on the user. In addition, feedback is important : people need to be able to track their progress. [11] People like to reflect on their daily activities, much as they do with a diary, and they can become quite attached to it as it provides them with a better understanding of what happens and why. [13] The goal setting theory here we have to goal of managing ones weight or obtaining a healthy lifestyle states the importance of feedback. If people do not know how they are doing, it is difficult or impossible for them to adjust the level or direction of their efforts or to adjust their performance strategies to match what the goal requires. [12] II. GOAL Quantified Self [14] is a technology movement that tries to accomplish selfknowledge through visualizing big data elements, including gamification elements and using sensory equipment in a mobile environment. By employing this in the project, the user can be triggered to discover flaws in his/her dietary habits or activity schedule. By gaining this insight, it is desirable that the user can draw enough conclusions and will get motivated or stimulated to turn bad habbits into good ones. This way the user can obtain a healthier lifestyle and, as a side effect, weight loss. III. RELATED WORK Currently there already exist many applications that try and accomplish similar effects. These applications are mostly based on the input of a user and this of both dietary consumption and activity logging. By comparing the existing applications, some strengths or weaknesses could be discovered. This can than be included in the design of Vittles. The following ap- plications were compared i.a.: Calorie Counter by FatSecret1 , 1http://www.fatsecret.com/
  • 2. MyFitnessPal2 , Weight Watcher Mobile3 . Upon comparing these applications, some important criteria were chosen. These criteria simplify the comparison and help with the creation of a benchmark where the important aspects are indicated. These criteria include the options of entering food elements as well as activities, setting (user defined) goals, inclusion of gamifications and/or a rewarding system, retrieving reports about the users progress or status and the social character (integration with social media or an ’in game’ friend list) of the application. As a conclusion of this study, it was found that currently only little automation is employed. In addition, most application do not point out weaknesses in the users lifestyle or caloric consumption. However, connections with friends, setting goals, facing challenges and getting visual feedback appear stimulat- ing. IV. DESIGN For the design of Vittles it is important to consider the way we expect users to provide input to the application. As seen in literature [15], this can be automated. This automation can be accomplished by letting the user take a picture of the meal he/she is consuming. This will mostly lower the amount of time that is requested from the user. However, the accuracy is often much lower than with manual input. Nonetheless, input of data should be fast and easy. [2] Next to chosing the way users will enter data, it is also important to select a device that will be employed by the application. Herein it is important to note that mobile appli- cations are widely used and can provide a unique mechanism for collecting dietary information that reduces the burden on record keepers. Also, the always-on and always-carried nature means that users can self-monitor anytime and anywhere. [2] This leaves the door open for either smartphones or tablets. Previously the importance of reports and feedback was already stressed. With this in mind, the application will mainly be developped for tablets, since these have bigger screens and users can browse through their reports more efficiently. Also, a thing to consider is when it is expected that the user enters information. For example this could be done at the beginning of the day. When working in a prospective manner, we could focus on advising the user to eat something healthy. Hereby the role of the application would be to point out better or healthier alternatives. On the other hand, the application could work in a retrospective way. Hereby, the user would enter what was eaten. Consequentially an advisatory approach would be less effective. In this approach it will be better to point out weaknesses and to prevent them from happening again. For the design of this application a retrospective approach was chosen. Finally, some design criteria were determined before starting with the actual design of the application. These criteria are important elements for reaching the goal of this research. The design criteria include: • Consistency: An important aspect of any good ap- plication, is consistency. For this study, this means that adding a food item should by similar to adding 2http://www.myfitnesspal.com/nl 3http://www.weightwatchers.be/templates/marketing/marketing utool 1col. aspx?pageid=9119636 an activity. Also, the transitions between screens, the coloring etc. should be similar. • Creating entries in the caloric diary: As with many of the reviewed applications, an important element of the application will be a diary. In this diary both food items and activities will be logged. However, adding something to the diary should be fast and easy. The user should be able to do it without having to doubt their actions and without losing too much valuable time. • Simplicity: For the application I do not expect the users to be experts in nutritional values of food items nor activities. Hence, the application should be easy to understand. Throwing around nutritional numbers might be handy to some, but it can also scare off others. Mainly in elements like own recipes, it seems unpractical to make the user work with nutritional values. The system should calculate the values auto- matically. • Social character: The application will work with an internal user base, where friends can be made. This will not be coupled to a profile on other social networks. Every user will get their own profile-page, where his/her badges and completed challenges can be consulted by their friends. In addition there will be a timeline-page, where a stream of updates from the users friends will appear. This social aspect could then be exploited so that users could stimulate each other to work towards a more healthy lifestyle. • Setting goals: The user should be able to set some goals for himself/herself. Upon creating an account the application will make a suggestion. However, at all times the user should be able to adapt the goal. In addition, the progress should be visualized in an way that is quick and easy to understand. Goals should not only be based on a weight loss/gain target and the user should be able to set more than one goal. When reaching a goal, the user should receive some reward. Next to actual goals, the system can register bad habits. When discovering such a bad habit, the user will receive an update containing a suggestion to change it. This could make it easier for the user to find the cause(s) of their unhealthy lifestyle and to change for the better. • Gamification: Badges, Challenges and Goals. They are important gamification aspects that will be included in the application. They should make the application more compelling, so that the user would remain stim- ulated to keep going and to work towards a more healthy lifestyle. V. METHODOLOGY: RAPID PROTOTYPING For the design of the application, an iterative method was chosen. Hereby, an initial prototype is constructed and then iteratively tested and adapted, so that a final (digital) design can be accomplished. The first two prototypes that were designed, were designed on paper. By designing on paper, it is easy to give the user an overview of the look and feel of the application
  • 3. Fig. 1: SUS scale [18] with the score for the second paper prototype. without having to spend too much time on the creation of the prototype. In case problems arise, the design can also be easily adapted, without having to concider the technical or monetary complications that could acompany an adaptation. For the evaluation of the paper prototypes a combination of widely used techniques were used. Firstly a think aloud user test [16] was conducted. With this test, the test person has to perform some predefined steps and in that way navigate through the application. This to discover if the test person had any difficulties with specific aspects of the prototype and whether or not some functionalities are highlighted appropri- ately. Secondly, the user was asked to fill in a questionnaire (after the think aloud test). This questionnaire contained three elements: • Personal questions: to get an idea about the back- ground of the user. In this section questions about their weight (problems) were asked. • SUS-questionnaire[17]: to (simply and easily) get an idea of the the usability and simplicity of the application. The SUS questionnaire can be translated to a score that represents the quality of the interface. An overview of meaning of the scores can be found in figure 1. • Detailled questions about the application: to get a better idea of (un)needed functionalities or other issues with the application. After the paper prototype was sufficiently evaluated, the transition to a digital version could be made. The digital version should resemble the paper version as much as possible. Again, this prototype is evaluated in a similar manner. TODO: something about the evaluation of the digital prototype. VI. OVERVIEW OF PROTOTYPES In this section the different prototypes that were developed are discussed together with their evaluation and the results. There were two paper prototypes developed, followed by one digital prototype. A. First paper prototype The first paper prototype was designed mainly in a digital environment. This was initially chosen to, on the one hand, easily get the look and feel of a digital application, and, on the other hand, since good tools exist for creating such prototypes. This prototype is shown in figure 2. This prototype was evaluated by only a little number of (a) The main screen (b) Food diary (c) Activity logbook (d) Report view Fig. 2: First paper prototype test users (four). This since the design was not immediately percieved as innovative. In addition, a lot of issues arised from this evaluation. Therefore, I decided to stop the development of this prototype and focused on changing the design. Important lessons learned from this evaluation was that at that point, the application appeared very click based and included a whole range of functionalities. Consequentially, the next iteration would have to focus more on creating a smooth flow of all operations and in addition, focus more on what the core functionalities are. B. Second paper prototype The second prototype (figure 3) introduced a different look and feel. Mainly the stream of adding items to the food and activity diary were completely adapted. This prototype was developed solely on paper. This made it faster and easier to develop, mainly because the tool that was used in the previous iteration was quite limited when considering non- standard visualisations. The evaluation of this prototype was done as described in section V. There were seven test persons involved in the test phase with ages between 21 and 25 years old. Four of the test persons had overweight and thus matched the target audience. The first issue that arised from the evaluation was that adding an item was mostly hard to find. However, there exists large consistency between the food diary and the activity logbook, since once the users knew how to use the food diary, they could easily work with the activity logbook as well. Another thing that came up during the think aloud tests, was that it is counterintuitive to enter data (like your weight) in a report view. Challenges and having a friend network are positively received by most test users. The SUS score of this evaluation was 81, which corresponds to the ’excellent’ label as shown in figure 1.
  • 4. (a) The main screen (b) Food diary (c) Adding to the food diary (d) Report view Fig. 3: Second paper prototype C. First digital prototype Since the second paper prototype did not introduce any major issues with the design or the usability, we transfered to a digital version (figure 4). This is mainly a digitalized version of the paper prototype from the previous iteration. Minor changes are made, so that they fit current flat design standards. TODO: write about the evaluation of this prototype. VII. SOFTWARE DESIGN (a) The main screen (b) Food diary (c) Adding to the food diary Fig. 4: First digital prototype TODO: figures of the software design with explanation of used technologies. VIII. EVALUATION TODO: the application will be used by multiple users for a longer period. The results from this will be mentionned here. IX. CONCLUSION In this paper a design is introduced that tries to stimulate users of all age categories who suffer from overweight or obesity to reach a healthier lifestyle and as a consequence lose weight. This is accomplished by a system of feedback through report views and goal setting, gamification aspects such as collecting badges and facing challenges and a social character that can be exploited to the benefit of the user. This design resulted in an mobile application, called Vitles, via rapid prototyping. This consists of different iterations, each having their own design, development and evaluation phase. TODO: formulate results at the end. REFERENCES [1] National voedings- en gezondheidsplan voor Belgi¨e, http: //www.health.belgium.be/eportal/Myhealth/Healthylife/Food/index. htm#.Umu0gZROokR, 2005 - 2010 . [2] SIX, Bethany L., et al. Evidence-based development of a mobile tele- phone food record. Journal of the American Dietetic Association, 2010, 110.1: 74-79. [3] TSAI, Christopher C., et al. Usability and feasibility of PmEB: a mobile phone application for monitoring real time caloric balance. Mobile networks and applications, 2007, 12.2-3: 173-184. [4] Wikipedia, http://en.wikipedia.org/wiki/Calorie. [5] KAYMAN, Susan; BRUVOLD, William; STERN, Judith S. Maintenance and relapse after weight loss in women: behavioral aspects. The Amer- ican journal of clinical nutrition, 1990, 52.5: 800-807. [6] Sparling, Phillip B., Neville Owen, Estelle V. Lambert, and William L. Haskell. Promoting physical activity: the new imperative for public health. Health Education Research 15, no. 3 (2000): 367-376. [7] MCGUIRE, Maureen T., et al. Long-term maintenance of weight loss: do people who lose weight through various weight loss methods use different behaviors to maintain their weight?. International journal of obesity, 1998, 22.6: 572-577. [8] TREMBLAY, Angelo; SIMONEAU, Jean-Aim; BOUCHARD, Claude. Impact of exercise intensity on body fatness and skeletal muscle metabolism. Metabolism, 1994, 43.7: 814-818. [9] BANDURA, Albert. Social cognitive theory: An agentic perspective. Annual review of psychology, 2001, 52.1: 1-26. [10] CULLEN, Karen Weber; BARANOWSKI, T. O. M.; SMITH, Stella P. Using goal setting as a strategy for dietary behavior change. Journal of the American Dietetic Association, 2001, 101.5: 562-566. [11] LOCKE, Edwin A.; LATHAM, Gary P. New directions in goal-setting theory. Current Directions in Psychological Science, 2006, 15.5: 265-268. [12] LOCKE, Edwin A.; LATHAM, Gary P. Building a practically useful theory of goal setting and task motivation: A 35-year odyssey. American psychologist, 2002, 57.9: 705. [13] PAVEL, Dana; CALLAGHAN, Vic; DEY, Anind K. Democratiza- tion of healthcare through self-monitoring technologies. In: Pervasive Computing Technologies for Healthcare (PervasiveHealth), 2010 4th International Conference on-NO PERMISSIONS. IEEE, 2010. p. 1-4. [14] Quantied Self Labs, Quantied Self Self Knowledge Through Num- bersQuantied Self Self Knowledge Through Numbers, 2012. [Online]. Available: http://quantiedself.com/ [15] CONNELLY, Kay H., et al., Mobile applications that empower people to monitor their personal health, e & i Elektrotechnik und Information- stechnik, 2006, 123.4: 124-128.
  • 5. [16] JASPERS, Monique WM, et al. The think aloud method: a guide to user interface design. International journal of medical informatics, 2004, 73.11: 781-795. [17] BROOKE, John. SUS-A quick and dirty usability scale. Usability evaluation in industry, 1996, 189: 194. [18] http://www.usabilityprofessionals.org/upa publications/jus/2009may/ images/bangor7 figure4.jpg