A Web Application for Improved Diabetes Care

Transcription

1 A Web Application for Improved Diabetes Care Item Type text; Electronic Thesis Authors De La Cruz, Haily Publisher The University of Arizona. Rights Copyright is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 29/09/ :36:55 Link to Item

2 {1}

3 {2}

4 Worldwide, an estimated 382 million number of people have diabetes (International Diabetes Federation). This estimate is projected to increase 55% in the next 21 years (International Diabetes Federation). Because of the nature of diabetes, diabetics need to periodically measure their blood glucose levels to ensure that they are within a medically safe range. Managing a one s blood glucose levels is much harder than it sounds. Blood glucose levels can be affected by something as simple as what you eat to something as difficult to pinpoint as how much stress you have or how much physical activity you have done. A fairly new type of service is emerging that provides diabetics with the tools to more clearly manage their disease. In this paper I take a close look at the existing work taking place with diabetic logbook applications, and I lay out my own designs for a diabetic logbook application that is both simple and novel. I discuss the implementation of my designs, the challenges faced, and the success of this project. {3}

5 An estimated 25.8 million Americans live with diabetes, and another 79 million Americans are estimated to have prediabetes (American Diabetes Association). In the United States, diabetes is the 7 th leading cause of death (Centers for Disease Control and Prevention). And the seriousness of this is not only limited to the United States: worldwide, an estimated 382 million number of people have diabetes (International Diabetes Federation). This estimate is projected to increase 55% in the next 21 years (International Diabetes Federation). One of the defining characteristics of long-term care for diabetics is the need for constant periodic measurements. While certain diabetic patients may need more frequent measurements than others, all diabetics make daily decisions that can improve or worsen their condition under diabetes. As the prevalence of diabetes continues to grow, so does the availability of resources related to long term diabetes care. These resources often involve an educational component or a digital logbook component. Resources that are educational help diabetics and their caretakers better understand what foods are appropriate to eat, how to better identify and respond to specific symptoms, which medications and treatment options are available, and other information that can help the patient better understand and better treat diabetes. Diabetic resources that offer digital logbooks provide a service that aids diabetic patients and their caretakers to periodically track key measurements. Because of the nature of diabetes, diabetics need to periodically measure their blood glucose levels to ensure that they are within a medically safe range. These digital logbooks not only give the patient the ability to keep a record of past glucose measurements, but they are also providing patients the ability to more closely monitor complementary measurements that affect blood glucose such as carbohydrate intake, physical activity, medication, weight, and more. This data can be incredibly empowering to the patients because it can help both the patient and his or her medical professional better understand the patient s own body and how it responds to different levels of blood glucose and to different medications. Digital logbooks have become increasingly available as both website services and mobile applications. This paper takes a close look at existing digital logbooks, proposes a new, improved product design, and evaluates an implementation of this design. {4}

6 The following applications are representative of the current market for diabetic logbooks. Each application is either one of the most popular applications or has some significant novelty that makes it stand out from other applications. SkyHealth s Glucose Buddy is one of the first major diabetic logbook applications. It currently stands as the #1 most popular Diabetic App in both itunes and Google Play (Apple Inc.; Google Inc). It also offers a web interface for its logbook at glucosebuddy.com. Figure 1: A view of Glucose Buddy's ios app. This is the screen for recording a medication entry. Glucose Buddy s novelty is the comprehensiveness of its digital logbook. Diabetics can use Glucose Buddy to add and view records for blood glucose, medication, carbohydrate intake (food), physical activity, HbA1C lab results, body weight, and blood pressure. Other key features in Glucose Buddy include basic graphical visualization of logbook entries, support for mobile reminders to log new data entries, and being able to export your logbook into PDF and CSV file formats. {5}

7 Medivo s OnTrack Diabetes is the #2 most popular diabetic logbook application on Google Play (Google Inc). Figure 2: The start screen for OnTrack Diabetes on Android with sample data. OnTrack s novelty lies in both its comprehensiveness and its polished user interface design. OnTrack supports recording measurements for blood glucose, carbohydrate intake, exercise, medications, body weight, blood pressure, HbA1C, and even body fat. Like other apps, OnTrack supports basic graphical visualization of logbook entries, support for mobile reminders to log new data entries, and being able to export your logbook into CSV, XML, and HTML file formats. Finally, OnTrack also offers the ability to compile and view logbook data in pre-defined contexts, called Reports, such as Glucose by Category and Average Glucose Statistics. {6}

8 Diabetes App is the #2 most popular diabetic logbook on the ios App Store (Apple Inc.). Figure 3: A screenshot of Diabetes App s extensive food tracking. Diabetes App s may have a generic name, but the application has a couple of novelties that no doubt influence the app s popularity. Diabetes App has an extensive food tracking system. Patients have access to a large nutritional database to aid with recording detailed food entries. The nutritional database helps users who don t know how to estimate the carbohydrate intake for a particular meal. The database also allows users to keep track of Calories, fiber, sugar, and protein. Lastly, the nutritional database offers support for users to build custom recipes, which consist of the combination of multiple database items into one complete meal. Diabetes App s second major novelty is its daily carb budgeting. Users can set daily goals for their carbohydrate intake. As users record what they eat throughout the day, they can see how well or how badly they are maintaining their budget. This instant feedback is a great way for diabetic patients to explore which foods are high and low in carbohydrates. Diabetes App also supports the common features of being able to record measurements for blood glucose, medication, physical activity, body weight, blood pressure, and even daily water consumption. Diabetes App also supports graphically visualizing logbook entries. {7}

9 interface. Glooko offers its services on both Android and ios systems as well as its own web Figure 4: Glooko s glucometer adapter for the iphone. Glooko s primary novelty is its physical adapter that can connect many types of glucometers to an Android or ios device. This allows the Glooko mobile app on these devices to automatically download and save glucometer readings into the app. Glooko, therefore, offers a faster way to add new logbook entries for blood glucose. Glooko also provides an online sync that allows users to review their logbook in multiple devices or on the web. Lastly, Glooko also provides a nutritional database for looking up the carbohydrate intake of different foods. Common features that Glooko also supports include recording measurements for medication, carbohydrate intake, and physical activity, visualization of logbook entries, and support for mobile reminders to log new data entries. {8}

10 TactioHealth is a general health logbook for diabetics and non-diabetics alike, but it offers features that cater to diabetics. It ranks #3 among top diabetic logbooks in the ios App Store (Apple Inc.). Figure 5: A view of TactioHealth s ios app highlighting many of the app s supported logbook entry types. TactioHealth offers several novel features that other logbooks do not offer. First, TactioHealth supports data synchronization from multiple types of medical devices. While it doesn t support syncing with glucometers, it supports data sync with select smart scales for body weight measurements, select smart blood pressure cuffs for blood pressure measurements, select step counters for daily step count data, and the RunKeeper fitness tracking application for physical activity data. TactioHealth also uniquely offers its users calculated health risks for Type 2 Diabetes, Metabolic Syndrome, and the Framingham Risk Score. Lastly, TactioHealth also offers a service that provides the user a personalized recommended daily nutrition plan based on their logbook entries. Other key features include a digital health coach, which is simply a combination of daily measurement reminders combined with lifestyle advice from the Centers for Disease Control and Prevention and World Health Organization. TactioHealth also supports attaching multimedia content like audio and photo to logbook entries. TactioHealth also supports {9}

11 recording entries for medication and cholesterol with visualization for all of its data. Lastly, TactioHealth users can export all of their data into a comprehensive report in PDF format. Figure 6: A view of Diabetes in Check s daily meal planner. Notice the calorie information available via their nutritional database. Diabetes in Check s primary novelty lies in its food tracking capabilities. With this ios app, users have access to a nutritional database that is catered directly to diabetics. Users can find recipes that are diabetic-friendly and have access to a general food guide of what is and isn t diabetic-friendly. Users can search the nutritional database by scanning barcodes, and they can use the database to build a daily meal plan. Common features that Diabetes in Check also supports include recording measurements for blood glucose, medication, physical activity, body weight, blood pressure, and cholesterol, visualization of logbook entries, and support for mobile reminders to log new data entries. {10}

12 Figure 7: Diabetik s insulin calculator. Diabetik is a quickly-growing ios app that provides a novel feature set that helps insulinprescribed Type I and Type II diabetics. Its primary novelty is its insulin calculator which helps the user calculate the appropriate insulin dose to take based on recently recorded carbohydrate intake. The calculator is customizable so as to match the individual patient s prescribed insulin use. A second novel feature in Diabetik is the ability to utilize the iphone s location detection services to offer glucose check reminders based on either time or location. Diabetik s other key features include the ability to record glucose measurements, medication, carbohydrate intake, and physical activity, visualization of logbook entries, and exporting logbook entries in CSV and PDF file formats. {11}

13 Figure 8: The start screen on Diabetes Companion s Android app with sample data. Diabetes Companion is designed primarily with Type I diabetics in mind, but Type II diabetics can also find value in this app. Diabetes Companion is the most unique of the apps reviewed in this paper. The companion is a diabetes monster represented by cute icons throughout the app. The companion represents a charming personification of the user s individual progression in Diabetes. The companion s state is based upon the logbook data that the user records using the app. The user is playfully challenged to tame your monster by improving problem areas. In effect, the application is providing to the user personalized goals and recommendations based on their logbook data. Diabetes Companion s second major novelty is how the user can tag individual logbook entries with a variety of information including location, a photograph, the user s mood, meal category, and other context information. The Diabetes Companion logbook supports records for blood glucose, medication, carbohydrate intake, and physical activity. The app supports visualization of logbook entries, exporting data to PDF, CSV, and Excel file formats, and mobile reminder for glucose checks and medication. {12}

14 Application Export Reminder Nutritional Glucometer Multi- Personalized Progress Formats Services Database Support Device Recommendation Tracking for Sync s Goals/Challenges Glucose Buddy OnTrack Diabetes Diabetes App Diabetik Diabetes in Check Glooko Diabetes Companion TactioHealth (challenges) (daily diet plans) (carb budgeting) Export Formats: These apps allow the user to export their data simply and easily into at least one format that can be shared with a doctor or caretaker, such as CSV or PDF. Reminder Services: These apps provide the user with a notification service that reminds him/her to perform at least one action for managing his/her Diabetes. Types of reminders include measuring blood glucose, taking medication, performing physical activity, etc. Nutritional Database: These apps simplify tracking carbohydrate intake by offering a database of know nutritional information for various food products. Typically such a database holds hundreds to thousands of items. Glucometer Support: These apps sync directly to glucometers to make blood glucose tracking quick and simple. Multi-Device Sync: These apps offer services on at least 2 different platforms. Apps restricted only to the ios platform or only to the Android platform are not included. {13}

15 Personalized Recommendations: These apps use the user s medical logbook to provide personalized recommendations, such as increasing weekly physical activity by 5 hours per week. (This not necessarily medical advice.) Progress Tracking for Goals/Challenges: These apps provide the user the means of monitoring progress towards a variety of specified goals or challenges. For example, if the user is attempting to increase physical activity by 5 hours this week, the app can show the user how far or close he/she is to achieving it. The core features that any diabetic logbook has include (1) the ability to track blood glucose levels, food, physical activity, medication (prescriptions, insulin, or both), and body weight, (2) visualization of the patient s logbook data, (3) the option to export or download logbook data into formats for personal backup storage or presentation to medical professionals, and (4) mobile reminders for glucose checks and medication. Glucose Buddy is the most popular app (in terms of total downloads), but this is likely due its being one of the oldest Diabetic management apps. The app s last update was in the summer of TactioHealth s applications provide the most comprehensive feature set for Diabetics, but it targets a wider audience than just Diabetics. Its primary benefits are nutrition management and weight management. Diabetik was the only app reviewed that offered an insulin calculator. Diabetes Companion is the most unique of apps reviewed. It is the only app reviewed that provides Diabetes-specific health recommendations based on the user s data. The app sets challenges for the user to tackle and monitor. It is one of the few apps that not only provides a logbook for personal data but it focuses on directly influencing changes in the patient s management of his or her diabetes. But overall, the focus of diabetes management applications is simply to record data. Any trends or newfound knowledge from the data is left solely for the patient and the medical professionals he seeks out for medical advice. But what about patients who don t have the skills necessary to accurately analyze their own data? What about patients who don t have frequent {14}

16 access to professional medical advice? Overall, diabetes management apps (with some exceptions) lack the ability to facilitate the user in learning from their data. The focus of these apps is to provide a digital logbook, instead of on driving and facilitating improvements in patient health. A strong way of aiding use analysis is by offering data-driven (non-medical) recommendations for small changes in the patient s lifestyle, such as increasing physical activity or decreasing average carbohydrate levels. Another primary problem is that most diabetes management apps lack any features that directly help or encourage the user to set and monitor long-term goals. With existing apps, monitoring long-term goals involves keeping track of information often not provided by these apps. Moreover, tracking increments in progress towards a goal can prove to be rewarding and motivational for the patient. Most apps do not directly support this. An opportunity to create a new, innovative diabetic logbook came with a collaboration with the University of Arizona s Artificial Intelligence Lab and their DiabeticLink project. DiabeticLink is a one-stop shop web portal currently in development by the Lab as a resource for diabetics and their caretakers. Prior to this project, DiabeticLink had no design for a diabetic logbook component. Such a component must be at least just as good as or better than existing solutions. After careful analysis of existing diabetic logbook applications, the following features are proposed for the DiabeticLink Tracking Module: Basic Logbook This feature is at the core of effective Diabetes management for the patient and it will be a key dependency for our proposed novelty. An adequate logbook will provide the tools to record and visualize measurements of blood glucose, medication, physical activity, carbohydrate intake, body weight, HbA1C lab results, and blood pressure. Export Formats This feature is a vital connection between the diabetic patient and his/her caretaker. Ideal file formats to support would be PDF and CSV. {15}

17 Reminder Services This feature helps ensure both that the patient accurately follows his/her recommended regimen and that the patient doesn t forget to log relevant activity. Nutritional Database This feature greatly facilitates the patient s ability to record his/her carbohydrate intake, removing a barrier that may otherwise impede collection of important data. Furthermore, DiabeticLink s Tracking Module can be truly novel by implementing the following features: Analytics/Trends: This feature improves the patient s analysis of their own data by organizing data in a way that makes sense and points out non-obvious patterns in the progression of their condition. Progress Tracking for Goals/Challenges: This feature facilitates the process of meeting long term health improvement goals. This will also work as a complimentary feature to alerts by allowing the means to follow up on recommendations as long-term goals. Due to implementation decisions already made for the larger DiabeticLink web portal, the Tracking Module was developed on an Apache web server running PHP with a supporting MySQL database server. At the time of this writing, DiabeticLink can be found at The two primary parts of designing each of the logbook entry types was (1) user interface/experience design, and (2) implementing the design. For data entry forms, it was important to design web forms that were simple and easy to understand while maintaining consistency across different entry types. The following figure shows an example of the final implementations for adding glucose entries and food entries. Notice that even though both forms are asking for different information, they share similarities in the positions of elements, white space, and color scheme. Furthermore, all entry types share the following fields: date, time (if applicable), and notes. Notes is an open ended field where the user can record qualitative information. {16}

18 Figure 9: The interface for adding a new glucose logbook entry (left), and the interface for adding new carbohydrate intake (right). Visualization is one of the features that the most time was spent on getting just right. One of the key characteristics of a personal logbook for the user is his/her ability to explore his/her past records and data. For this reason, our data visualization for each entry type displays records in two key display formats: a graphical chart, and a table of data. Figure 10: The visualization page for glucose entries, populated with sample data. First, for almost every entry type in the logbook, we display the user s recent records in a graphical chart like above. Visualization provides the user the ability to quickly and intuitively see patterns in their recent behavior. Charts were implemented using a charting library called Highcharts. {17}

19 Figure 11: Sample glucose entries presented in a table format. Second, each logbook entry can be viewed in a tabular format. The primary benefit of the tabular format is the ability to view entries in a similar format to how the entries were added. It also provides a way for the data points to be viewed in a format that is closer to raw, where conclusions from the data are less easily drawn out. Lastly, the visualization pages for each of the entry types offer filter options, which allow the user to search through his/her logbook data by date range, category, and other criteria. For example, in the glucose visualization page, the user can change the date range, the category of glucose measurement, and even symptoms that the user may have logged. Figure 12: Filter options in the glucose visualization page. {18}

20 The DiabeticLink Tracking module offers two primary means of exporting logbook data: (1) the user can print the webpage into a PDF file, and (2) the table can be downloaded as a CSV file. Figure 13: The print option, directly above the chart (left), and the option for exporting to CSV directly above the data table (right). Designs were made to integrate with the FatSecret API to provide users with a comprehensive, growing database of nutritional information. But complications with licensing and a lack of time made it not possible for a nutritional database to be currently implemented. The purpose of a Trends page is to both organize the entirety of the patient s data and to show important patterns in the patient s data that are both highly valuable for monitoring the patient s progression and not obvious when looking at individual records. The idea is to show information that a medical professional would want to see but formatting it in a way that a patient would understand. This feature was previously considered as Health Alerts, but based on feedback and brainstorming, we found that sending this type of information as a series of alerts or notifications for the user would be both inconvenient, repetitive, unnecessary, and even problematic. Instead, this information ought to be displayed dynamically in an accessible report, like this Trends page. This was a great learning experience on the benefits of iterative product design. {19}

21 Although not yet implemented, the design for the Trends page is mature and contains the following components: Dynamic Date Rages: data can be displayed on a weekly and monthly basis. Key Indicator: This page calculates an estimated HbA1C reading based on the patients average glucose levels for evaluation of periodic improvements and declinations in care. Multiple Indicators: This page will include a multitude of charts (i.e. Glucose, Carbs, Activity, Medication, etc.) with the intention of painting a complete picture of the week s or month s progress. Figure 14: Concept mock-up of the Trends page. While the rest of DiabeticLink is great for day-to-day measurements, implementing a goal tracking feature is meant fill the gap in the existing market where patients do not have an easy way to maintain status on the status of long-term goals. In this feature, patients will be able to monitor progress on long terms goals related to their Diabetic logbook. Goals can include weight loss, weight gain, exercise goals, carb budgeting, and more. A goal is defined as a desired measurement with a time deadline. Progress towards completing a goal can be measured and tracked over time. Goals are characterized by the following key characteristics: Desired Measurement: a numeric measurement that the user is striving for. Example measurements include total daily carbs = 100 g, average total daily carbs over 5 consecutive days = 100g Goal Start Date: the date that the user began working towards the goal. This is used to aid tracking how long a goal took to achieve. Desired Completion Date: the date that the user aims to meet their goal by. Actual Completion Date: the date that the user met his/her goal. {20}

22 This feature will also be made up of the following components: Custom Goals: Patients can define their own goals, with their own success criteria. Suggested Goals: These can be automatically generated by Health Alerts. Progress Indicators: Much like personalized recommendations, patients will see progress indicators for their currently active goals in logbook visualization pages. Figure 15: A concept mock-up of how to visualize goal progress. To better understand Goal Tracking, consider the following example goal definition (also represented in Figure 14): Desired Measurement: Blood glucose level less than 180 for 7 consecutive days. Goal Start Date: July 10 th Desired Completion Date: August 10 th Actual Completion Date: July 30 th A fault in my design phase was that it lacked any plan for how to properly deal with time zones. Midway through the project, lack of time zone support started introducing problems into basic user testing. But solving this was no simple task. I had several questions to answer: How should date and time information be represented in the database? What built in functions did PHP or MySQL have for facilitating time zone support? How do we (if at all) ask the user to specify his/her time zone? How can this preference be represented in the database? How can we deal with Daylight Savings Time? The first question I sought to solve was how to best ask the user to specify his/her time zone. I oversimplified this solution by simply asking for a UTC offset from the user. This {21}

23 approach had two main problems. (1) It was a confusing question from a usability perspective. Users don t inherently know the number of hours between their current time zone and UTC. (2) This solution also didn t handle Daylight Savings Time at all. The solution to these questions laid in PHP s built in DateTime and DateTimeZone classes. As you can see in Figure 16, we ask the user to specify which region they place into. The list is also grouped by larger regions as well. This list of regions is the list of supported time zones within PHP s date time support. Furthermore, this handles local daylight savings rules very well because of PHP s timezonedb module which stays up-to-date with local changes in daylight saving rules (Rethans). Next, when storing date and time information into the database, we convert it all to UTC time. We then use this saved user preference to convert UTC date and time entries in the database to the user s local time zone. The resulting solution is one that (1) handles time zones and daylight savings time well, (2) offers better user experience and less confusion, and (3) is flexible to accommodate changes in the user s time zone. Figure 16: A view of the Time Zone preference option for users. Even though the Tracking Module is an addition the DiabeticLink website, within the module, I had a certain amount of flexibility in defining the overall webpage design. From the beginning, I maintained a design that was both clear, simple, and functional. The navigation links on the left pane, with the links that I believe to be the most commonly used being placed {22}

24 at the top of the pane. Lastly, the web design is responsive to changes in the browser window size. This means that it automatically resizes and shifts the location of different elements of the webpage to support smaller screens such as mobile. Figure 17: The insulin visualization page as seen with a mobile device. Even though the Tracking Module as it is now is not yet fully implemented, it has a feature set that matches many existing applications. The core strength of the DiabeticLink Tracking module is its comprehensive logbook. Even though I did not have the time to implement some of the more novel ideas into the module, taking the time to make sure that the core functionality of the tracking module was well designed, well-polished, and well tested proved to be worth it. The core logbook features provide the primary benefit to the user. The Trends and Goal Tracking features are complementary features that rely on a robust logbook system at the core of the website. The second major strength of the module is its data visualization. Patients can view their logbook entries in multiple formats. Visualization and data presentation both deeply impact the user s ability to understand his/her data. Consequently, visualization has a deep impact in the user s ability to understand his/her diabetes. The action of logging and reviewing personal medical data in this application is empowering to the diabetic user because it makes more clear the causes behind sudden spikes in blood glucose, can help explain the occurrence of certain symptoms, or visualize the relationship between high-carb foods and high glucose levels. Giving the user the ability to explore their data potentially helps him/her manage his/her diabetes. {23}

25 The Tracking module currently has two large problems. First, without the Trends and Goal Tracking features, the application is not entirely novel. While it is a reasonably welldesigned application, its current selling point is that it s a part of DiabeticLink. There is a chance here to build an application that is truly unique and helpful for Diabetics at the same time. The second large problem facing DiabeticLink s Tracking Module is low adoption. Even though the website is live, marketing is virtually nonexistent. Current user adoption is limited to word-of-mouth marketing, which hasn t result in anything close to a critical mass of adoption. Unfortunately, with product design, web programming, and web user experience design in this project, marketing and promoting the application was out-of-scope of this endeavor. For many patients, diabetes is a crippling and confusing disease to manage. Diabetic logbook applications are increasingly becoming a popular tool for diabetics to maintain healthy blood glucose levels. After reviewing the current market of diabetic logbook applications, I set out to design, implement, and publish a new and novel application for DiabeticLink s Tracking Module. Although not all designs are fully implemented yet, DiabeticLink s Tracking Module is a reliable application that can add value to any diabetic. I learned a lot during the entirety of this project. I learned about product design, market analysis, user experience and user interface design, and more. I experienced first-hand the frustrating challenges of both developing a website on a time schedule and of dealing with design problems that were unintentionally overlooked. The skills I have acquired throughout this project will undoubtedly serve me well in future large scale projects. {24}

26 American Diabetes Association. "FAST FACTS: Data and Statistics about Diabetes." March Diabetes.org. 1 May < %20Sean/FastFacts%20March% pdf>. Apple Inc. "Medical - App Store Downloads on itunes." n.d. itunes. 3 May < BHI Technologies, Inc. "Diabetes App Lite - blood sugar control, glucose tracker and carb counter." 14 November itunes. 2 May < Centers for Disease Control and Prevention. "Deaths: Final Data for 2010." National Vital Statistics Reports 8 May 2013: 1. < Everyday Health, Inc. "Diabetes In Check." 28 April itunes. 2 May < Giacomelli, Nial and Jeremy Swinnen. Diabetik - A free, open source diabetes management application for the iphone and ipad. 14 February May < Glooko, Inc. Glooko Mobile Diabetes Management Blood Glucose Log May < Google Inc. "Medical - Android Apps on Google Play." n.d. Google Play. 3 May < International Diabetes Federation. "Diabetes: Facts and Figures." n.d. IDF.org. 1 May < Medivo. "OnTrack Diabetes - Android Apps on Google Play." 30 January Google Play. 2 May < {25}

27 mysugr Inc. "mysugr Companion Diabetes Manager for iphone, ipad and ipod." mysugr. 5 May < Rethans, Derick. "PECL :: Package :: timezonedb." 15 October PECL. 5 May < SkyHealth. Glucose Buddy. n.d. 2 May < {26}