Exploring the User Experience in Continuous Glucose Monitoring Systems

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Exploring the User Experience

in Continuous Glucose

Monitoring Systems

Undersökning av Användarupplevelse

i Kontinuerliga Glukosövervakningssystem

Sabina Forsberg

Sara Olsson

Computer and Information Science Bachelor

15 credits Spring/2018

Supervisor: Romina Spalazzese Examinator: Dipak Surie

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Abstract

Type 1 diabetes requires proper supervision day and night to maintain a healthy living. To manage diabetes research shows that people today more often use Continuous Glucose Monitoring (CGM). This system measures the blood glucose levels through a sensor placed to the users skin. The user then scans the sensor with a hand device or mobile application to get a reading of current blood glucose level and in which direction the levels are heading. Researchers suggests that to be able to create the best user experience solution for diabetes patients, the designers truly need to understand the users and the way that they interact with their monitoring systems, which is the goal of this study. The problems with current diabetes monitoring systems is, in most cases, the unclear structure of the navigation and lack of thoughtful and meaningful user experience. Due to the complexity of the disease, labeling is vital to make users understand the interface. This is a area that most studies acknowledges, but a well thought out solution has not yet been presented. The central part of making users understand the information is to involve end users in the designprocess. Medical information can be hard to grasp and when a lot of information is presented it can lead to information overload. Patients want a well designed tool to help manage their disease. Previous studies shows that patients want to have one system for all their functions, a so called system of systems, rather than having multiple ones.

This study aims to examine three of the available products on the Swedish market to understand the user-needs and the user experience of these products. Through a interviews and survey with end users, data is collected to evaluate currently used products. The data from the first phase is analyzed and findings then lay the foundation for the next phase, where a prototype is made. The prototype is designed to validate the findings of user-needs in terms of navigation structure and user experience from the first phase. The validation is conducted through a second survey where the end users are asked to compare currently used product versus the prototype, alongside with the predetermined questions in System Usability Scale (SUS).

The results shows that user experience in CGM systems needs further development to make the patients satisﬁed in the way that they can manage their disease. This study suggests that by designing with the gestalt laws in mind, a better navigation structure and information presentation is possible. But also suggests that future research within the technical solution of making the CGM systems to a system of system, is required.

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Abstrakt

Typ 1-diabetes kräver ordentlig uppsyn dag och natt för att upprätthålla ett fungerande liv. Idag använder människor allt oftare kontinuerlig glukosövervakning (CGM) för att hantera sin diabetessjukdom. Detta system mäter blodsockernivån genom en sensor som placeras på användarens hud. Användaren skannar sedan sensorn med en handenhet eller mobilapplikation för att läsa av den nuvarande blodsockernivån och i vilken riktning blodsockret är på väg. Forskare föreslår att för att kunna skapa den bästa användarupplevelsen för diabetespatienter måste designers verkligen förstå användarna och hur de interagerar med sina CGM-system, vilket är målet med denna studie.

Problemen med nuvarande CGM-system är att i många fall upplevs navigeringsstrukturen som otydlig och att det finns brister i användarupplevelsen. På grund av sjukdomens komplexitet är kategorisering i navigeringen avgörande för att användarna ska kunna förstå gränssnittet. Det här är ett område som de flesta studier tar upp, men en väl utformad lösning har ännu inte presenterats. Den centrala delen för att användarna ska kunna förstå informationen är genom att involvera slutanvändare i designprocessen. Medicinsk information kan vara svår att förstå och när denna information presenteras kan användaren få en känsla av ”information overload”. Patienterna vill ha ett väl utformat verktyg för att hantera sin sjukdom. Tidigare studier visar även att patienter vill ha ett system för alla sina behov, ett så kallat ”system of systems”, snarare än flera separata system.

Denna studie syftar till att undersöka tre av de tillgängliga produkterna på den svenska marknaden för att förstå användarens behov och användarupplevelsen av dessa produkter. Genom en intervju och enkätundersökning med slutanvändare samlas data in för att utvärdera de produkter som används idag. Resultatet från den första fasen analyseras och fynden lägger sedan grund för nästa fas, där en prototyp utvecklas. Prototypen är utformad för att validera resultatet av den nya navigeringsstrukturen och användarupplevelsen utifrån de problemområden som uppgetts i första fasen av studien. Valideringen görs genom ytterligare en enkätundersökning där deltagarna får jämföra sin nuvarande produkt med den utvecklade prototypen, i samband med de förutbestämda frågorna i System Usability Scale (SUS).

Denna studie visar på att det är möjligt att skapa en bättre navigationsstruktur och informationspresentation med gestaltlagarna i åtanke. Dock påpekas även behovet av att utföra ytterligare forskning av den tekniska lösning som krävs för att möjliggöra ett “system of system” för CGM-systemen.

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Abbreviations

BGM Blood Glucose Monitoring CGM Continuous Glucose Monitoring FGM Flash Glucose Monitoring GDB Gestational Diabetes Mellitus HCI Human Computer Interaction UD Universal Design

UI User Interface UX User Experience

Deﬁnitions

System of Systems When referring to the term System of Systems in this study the (SoS) following deﬁnition applies:

”Directed. The SoS is built to fulﬁll speciﬁc purposes. Constituent systems have the ability to operate independently, but are managed to satisfy a concrete purpose” [1].

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1. Introduction

Diabetes is a condition where the pancreas either do not create the hormone insulin or where the body is unable to incept the produced insulin correctly [2, 3]. The hormone, insulin, operates to enable the glucose ingested from food and drinks containing carbohydrates to pass from the bloodstream into the body’s cells. This produces energy, and without a functioning production of this hormone, the glucose levels in the blood will be higher than what is called ”normal”, also known as hyperglycemia. If not dealt with, long-term high glucose levels correlate with diﬀerent kinds of organ and tissue failures, other body suﬀerings and even death [2, 3].

There are different ways to monitor the disease properly. The most accurate way to measure the blood glucose levels are through a blood sample from the patients fingertip. [4]. But this way of measuring can cause discomfort for the patients in the sense where they have to do this process between 10-20 times per day. A new way of measuring blood glucose levels are through Continuous Glucose Monitoring (CGM) systems. The patients will put a sensor with a small needle on their body and the sensor measures the blood glucose levels continuously. Then the patients can scan the sensor with a hand device or mobile application and get their current levels and also in what direction the levels are heading. This reduces the discomfort of taking a blood sample through the finger multiple times per day [5].

Even though that the CGM systems are vital for the patients to manage their disease properly, they can seem hard to understand and use for people not familiar with them. For example, parents will have to leave their children at daycare or school and depend on that the staﬀ can manage their child’s diabetes in a correct manner. This is one of the reasons why there may be room to improve the user experience of these products.

Because of the severity of the disease and the importance of a correct management, this study focuses on the scope of exploring the user-needs and user experience of CGM systems. This study is built on three CGM products available on the Swedish market and research questions will aim to answer what people feel about currently used CGM systems and if the user experience can be improved.

A state of the art will describe the research that has been made up until now and through this study a research gap within the ﬁeld of user experience in these systems will be ﬁlled.

1.1 Diﬀerent Types of Diabetes

There are diﬀerent kinds of diabetes which requires diﬀerent types of supervision and considerations.

Type 1 diabetes is when the body's immune system attacks the cells that produce insulin. This means that the pancreas produces very little or no insulin at all. Why this occurs is still unknown. This disease often develops in younger years, though it can be developed at all ages. All people with type 1 diabetes need to have close supervision of their glucose levels in the blood and need to inject insulin to their bodies to survive [2, 3].

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Type 2 diabetes constitutes at least 90% of all cases of diabetes. This condition means that there is a relative insulin deﬁciency, which means that the body produces some insulin but not enough, or insulin resistance. This type can occur at any age and diagnosis is often made when a complication appears or when a routine checkup of blood or urine is performed. This means that the disease can go undetected for many years. The main reason for type 2 diabetes is overweight or obesity, which itself can lead to high blood glucose levels or insulin resistance. But in some cases, it emerges for unknown reasons. The people diagnosed with type 2 diabetes can often manage their disease by exercising and by maintaining a controlled diet, but over time oral drugs or insulin can be necessary [2, 3].

In addition to type 1 and type 2, there is a form of diabetes which may occur to pregnant women - Gestational Diabetes Mellitus (GDM). This means that the blood glucose levels are abnormally high during the pregnancy but usually dissolves after childbirth. However, the risk of developing type 2 diabetes later in life, will increase for both the mother and the child. One in 25 of women worldwide is diagnosed with GDM while pregnant, and roughly half of the mothers will develop type 2 diabetes subsequently [2, 3].

A number of serious health problems can occur if the condition is not managed in a correct way. Consistent high blood glucose levels can lead to serious diseases aﬀecting heart and blood vessels, eyes, kidneys, nerves and teeth. People with diabetes also have a greater risk of developing infections. Cardiovascular disease, blindness, kidney failure and lower limb amputation is in almost every high-income country caused by diabetes. By monitoring the blood glucose levels and making sure that they are within ”normal” levels, the risk of getting a complication or sequela is less likely [2, 3].

1.1.1 Monitoring the Blood Glucose Levels

To ensure proper supervision of type 1 diabetes, it is essential that the diagnosed person monitor and control the blood glucose levels several times each day. By doing this, they will know what options they have regarding what to eat and drink, if they should exercise, and how to medicate at the moment. If the levels are not within the correct margins, it will have to be adjusted [2, 3].

There are different ways to check the blood glucose levels. For a long time the most common way, was to measure the blood glucose levels through a small, portable machine called Blood Glucose Monitoring (BGM), which enables people to check their levels wherever and whenever they feel it’s needed. To use the BGM, a drop of blood is obtained from the fingertip with a small needle (lancet) and the blood is then placed on a test strip connected to the compact machine. This process needs to be practiced continuously over the day to keep track of the blood glucose levels, as it only measure the levels in real time, and not where the blood glucose levels are progressing towards. To use BGM is still the most accurate way to measure blood glucose levels, but it has side effects such as perforations, numbness in the fingertips, e.g. [4].

A more modern way to measure blood glucose levels is through Continuous Glucose Monitoring (CGM). This is a system that can be checked wherever and whenever

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throughout the day and night. To get the blood glucose level the CGM system is used to scan the sensor. This system will not only check current blood glucose levels, but will also provide changes over time, overlook of trends and if the blood glucose levels is heading up, down or is staying on a good level, which is preferable. This provides a informative guide to make good decisions in food, exercise and medication to maintain a good balance [5].

To use a CGM system, a small sensor is placed on the skin (most often on the back of the upper arm or on the stomach), which measures the blood glucose levels between the cells every other minute. Then the result is sent to a monitor, which can be either a separate device, a insulin pump, a smartphone or tablet [5].

This technology encourages a simpler, more discrete way to supervise the condition, and the diﬀerent companies who developed these systems continuously try to implement new features to make the system more useful. Most of the times, the user still have to use BGM twice a day to ensure that the CGM system is accurate [6].

This study examines three diﬀerent CGM systems available on the Swedish market. Due to ethical considerations the products will remain anonymous throughout the study and will be referred to as Product A, B and C. The product, or the companies behind the product, is irrelevant to the result because this study aims to examine future developments of the CGM system.

Table 1: Outlines the diﬀerences between the CGM systems used in this study.

1.2 Research Questions

This study aims to explore the user-needs of the people diagnosed with type 1 diabetes in Sweden. The goal is to find out what features they would like to have in future CGM systems and how they should be designed. This will be explored through different steps, where the first phase is to understand the user and their needs. Data is collected by examining existing products on the Swedish market. Through interviews and surveys the end users answer questions about their currently used product and its features.

Product A Product B Product C

Sensor Durability 14 days 7 days 8 days

Mobile Application Yes Yes No

CGM Integrated with Pump No No Yes

Follow-Function No Yes No

Alarm Function No Yes Yes

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After collecting requirements, the study proceeds to the prototyping phase where the analysed data from the ﬁrst phase is put into context. The last phase will cover the evaluation where the same end users will examine the prototype and reﬂect on the user experience. The reason for using the same participants is to ensure that their expectations are met.

This result will uncover design possibilities and future developments within CGM systems to help ensure better user experience for patients with type 1 diabetes. User experience refers to how the user feel about the product, and that the information is useful, usable, desirable, ﬁndable, accessible and credible [7].

To understand the CGM systems, its users and the way the users want to be able to use these products, the following question will be answered:

1. “How do Swedish people diagnosed with type 1 diabetes experience the Continuous Glucose Monitoring System that they use today?” 

The data from research question 1 will be the foundation to answer research question 2:  2. ”Can the user experience of the Continuous Glucose Monitoring System be improved to

help simplify the lives of people diagnosed with type 1 diabetes, and in that case how?”

1.3 Previous Research

A literature study review was made with the purpose to examine the state of the art of previous research within the areas of Glucose Monitoring, User Experience and the Design of Systems made for people diagnosed with Diabetes.

1.3.1 Design for the Best User Experience

Previous work outlines the importance of designing the right product for people with disabilities, such as diabetes [6]. For many years people have researched the possibilities of making lives easier for the diagnosed people [8]. Diabetes is a complex disease where the users’ needs should be in focus when designing these systems [9]. Monitoring user behaviors over time will give a good sense of the user-needs and also how an application should be developed. In short terms, it is important to ensure usability to provide a good experience for the users [9]. When the designer truly understands the user-needs, they can create the best solution for the users [6]. That is why this study is important for future development of diabetes systems and its user experience.

Norman and Nielsen, who are considered experts in the ﬁeld of usability and usability studies, states that interfaces of smartphones in some cases are taking a step backwards in the development because design principles and guidelines of Human Computer Interaction (HCI) is ignored when designing an application [9]. Qualitative questions to the end users about overall experience, features, products and the perceived quality, can be considered the appropriate way to go when creating an application that is technically,

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medically and behaviorally sound [9, 10]. It would take specialists in application design, user experience design and user interface design and also specialists within the areas of diabetes and any complications caused by the disease [9]. In terms of functionality, specialist within the area suggest that large buttons, no scrollbars and minimal typing is preferable. Users want to be able to navigate the application easily without accidentally navigation to other pages [9].

Researchers suggest different kind of approaches for developing products with good user experience [6]. From a user centered design approach an application should fit smoothly into the living routines of the end users, require minimum of new technical skills and be perceived as easy to use [11]. Universal Design is one of these approaches and it contains seven principles with the goal of presenting a product that is universal in its nature [6]. The key factors of the principles is simplicity and intuitive usage, works for any group of users, communicates necessary information in a effective way, minimizes the chances of errors, can be used with individual preferences and abilities, low physical effort needed and can be used by every user regardless of mobility [6]. A recurrent question in the previous work is if the product can be used effectively. Researchers investigate this question in different ways, and one of them is by evaluating existing websites and the medical information on these websites. The amount of information on these websites can be overwhelming, confusing and frustrating even by the most experienced users. And the understanding of medical knowledge can be challenging when content seems disorganized and difficult, which may result in information overload [12].

Due to the enormous amount of information on these websites, labeling is an important part of ﬁnding the right content and should be highly prioritized when designing websites with medical information that can be perceived as hard to grasp [12]. These discoveries were made by experts in the ﬁeld, and no usability testing was made by any end users to validate their results [12].

1.3.2 Diagnosing and Maintaining Diabetes with Systems

Previous work shows that there have been many attempts to use computerized systems to diagnose diabetes, but with most of these systems, the person still has to go through medical tests to get the data for the computerized diagnostic system [13]. One of these systems is called Ubiquitous Health Monitoring Systems and is built to support the needs of continuously monitoring human health conditions. By using these systems, previous work shows that irregular vital signs, such as heart rate variability, diabetes symptoms and others, can be detected and treated early. A person’s health condition can be determined by the data instituted by vital signs [8]. Some researchers have proposed a model called Neutral Network [13]. This is an intelligent and eﬀective methodology for automated detection of diabetes, where there is only need to provide some physical parameters to the system. Based on these physical parameters and early stage diabetes symptoms, an estimation is made [13].

The world is getting more wireless by the minute and so is the Internet Health or eHealth. Mobility and reduced location dependencies is the new way of living and a new branch of eHealth is developed, called Mobile Health or mHealth, which introduces new ways to use

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computing resources [14]. In Sweden alone, mHealth is mostly stand-alone applications for supporting self-management of chronic diseases and support of healthy lifestyle choices. Ongoing research projects is putting mHealth into context through design, usability, accessibility and user experience from both the patients and the healthcare teams perspective. The current technologies used in Sweden is poorly integrated in the sense where patients cannot send their values directly to the hospital due to the hospitals regulations. Instead patients must manually report their values on the hospital website and the hospital staff must then interpret the data. This can lead to human errors and cause life threatening conditions and in the long run lead to death [14]. Both patients and healthcare staff are longing for a better integrated solution and think that another stand alone application would mean adding to the difficulties and frustration of the healthcare staff and patients, rather than supporting the cause [14].

Patients and nurses have participated in interviews to examine motivations, expectations, needs and positive or negative experiences with use of web applications. The negative opinions has mostly been about unclear structure of the websites navigation [15].

There are thousands of health and wellness applications available for smartphones nowadays. Yet, these applications do not have all the behavioral strategies necessary for people to fully manage their diseases, especially for older and less healthy users [9]. The older generation sometimes feel confused by technical solutions and require feedback in order to comprehend. Previous work [16] shows that a computer assistant with diﬀerent feedback styles can improve troubleshooting technical failures of patients self-managing systems at home. A smart home environment would be a beneﬁcial solution for both patient and healthcare center [16]. Although medical systems may be described as easy to use by the younger generation, the older generation may feel the contrary [16].

1.3.3 Maintaining a Healthy Lifestyle with Diabetes

Negative emotions due to bad blood glucose values can cause a strain between child and parents. Research shows that subtle feedback of blood glucose levels will ease the negative emotional response and help with sustainable use [17]. Other circumstances like growth and menstrual cycle can result in bad blood glucose levels and create anxiety for both child and parent. The parents anxious reaction to these results can lead to children not telling their parents about bad blood glucose levels, which can cause hyperglycemia or hypoglycemia [17]. With education and understanding for these circumstances, the child and parents can more easily understand that during these periods they may need to manage their disease diﬀerently to get good results, and that in its turn can oﬀer some emotional relief [17].

A common way to collect data is through eye-tracking, a technique used to track the users eye-movement. This technique provides more accurate data than the traditional speak aloud protocols, because it captures data that users may not be aware of [9]. Web applications is seen as a good supplement to regular diabetes care and helps the user to maintain control over their diabetes condition. A big part of being successful in managing the diabetes is that the diagnosed person has a more active role in their care.

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This means educating themselves and monitoring their disease closely to prevent complications [15]. Patients need to be proactive in their care and a recurrent topic is how to activate diabetes patients in self-management and giving the patients tools to enhance their self-management capabilities [11]. When healthcare solutions is used in a simple and interactive way, the patients see it as a complementing tool to help manage and take charge of their disease [15].

1.3.4 Holistic Approach for Diabetes Management

Previous studies have shown that users want the ability to sync their diabetes monitoring application with other applications, like diet tracking and to automatically track physical activity rather than manually entering the data [9].

Researchers have tried to find a holistic approach and to avoid isolated activities in diabetes applications. To do this, they have gathered and compared user-need elicitation and design phases [11]. When integrating different systems into one, it’s important to have a consistent and pervasive interface to achieve the best usability for the users. If different systems are combined in a new system, also known as System of Systems, it should be evaluated by experts and also tested by real users to ensure that the interface is modified to best support the users needs [18].

The problems with current diabetes monitoring systems is, in most cases, the unclear structure of the navigation and lack of thoughtful and meaningful user experience. Due to the complexity of the disease, labeling is vital to make users understand the interface. This is a area that most studies acknowledges, but an well thought out solution has not yet been presented. The central part of making users understand the information is to involve end users in the design process. Medical information can be hard to grasp and when a lot of information is presented the reaction can be information overload. Patients want a well designed tool to help manage their disease. Previous studies shows that patients want to have one system for all their functions, a so called system of systems, rather than having multiple ones. How to ﬁll the research gap concerning this area is presented in the purpose below.

1.4 Purpose of this Study

The purpose of this study is to explore how users feels about their current CGM systems, what features they would like to have in future developments and if the user experience can be enhanced. The importance of having a proper system to monitor and manage type 1 diabetes is vital. And in order for the designers to be able to create the best user experience solution, they truly have to understand the user-needs. By interviewing and collecting data from a large group of end users this study have the opportunity to find and fill the research gap of how CGM systems work today and what can be improved and developed differently in user experience and future design. Through prototyping a new solution will be conducted where the user experience is the main focus area. The prototype is then evaluated by the same end users as in the first phase of this study.

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1.5 Limitations of Context

This study is conducted with some constraints in mind. First of all, the study focuses only on type 1 diabetes, as CGM systems almost solely is used by patients with this type of diabetes. The interviews and surveys were therefore conducted with people diagnosed with type 1 diabetes.

This research explores the products available for the users on Swedish market, because this is the end users that will participate in this study. Thus the limitation to exclude products and features not available to the end users. The interview and surveys were only answered by Swedish people using Swedish products.

As this study focuses on the design and user experience of CGM systems, a decision to exclude the technical part of the products was made. This research focuses on exploring the needs of the users, the experience of these CGM systems and not the technical solution behind it. For example, this study outlines the design of a system of system but not the functions behind the interface.

2. Method

The following chapter covers the qualitative perspectives, quantitative perspectives, methods, the method selection, selection of users material, and ethical considerations. The methods used in this study is both measured in a qualitative and quantitative way, working with a semi-structured interviews, surveys, prototyping, and validation of the result. The data that the users provide in the ﬁrst phase is analyzed and lays the foundation of how the prototype is designed and created. The goal of the prototype is to provide a new solution of how future CGM systems can be designed with navigation structure and user experience in mind.

The first phase of the study starts off with a qualitative semi-structured interview to enhance the understanding of what people in Sweden with type 1 diabetes want in future CGM systems to improve their daily life. Then the first survey is sent out to end users to both qualitatively and quantitatively evaluate what they think about their currently used system. In the second phase a prototype was developed with participatory design based on the results collected in the first phase. The participants from the semi-structured interview was involved in the process of making the prototype and gave iterative feedback during the whole process. The third phase attempts to validate the findings from the first phase through a quantitative second survey.

2.1 Method Selection

To answer research question 1, the method covers a formative approach [19, pp. 42], a semi-structured interview (moderated) is conducted. And then a online form (unmoderated) is sent out to two diﬀerent large communities. The formative approach is used to get at better understanding of what the end users think about the design of the CGM systems and how user experience of these systems can be enhanced.

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The semi-structured interview reveals detailed information of how the systems work today and which changes and developments the participants would like to have in the future. With this in mind the ﬁrst survey is sent out to the communities.

After performing the formative approach, a summative approach is performed to answer research question 2, where the answers collected in the ﬁrst phase is analysed and put into context in the second phase, where the prototype is developed [19, pp. 43]. The third phase contains instructions on how to test the prototype and then answering the questions of the second survey to validate the result. Below is a visualization of the methods in a sequential order:

2.2.1 Method for the Semi-Structured Interviews

The moderated semi-structured interview is accomplished in an open setting with two participants present at the same time. The session is recorded, which the participants gave oral consent to. The purpose is to get more speciﬁc information in a qualitative way before making the ﬁrst survey. The main focus during the interview is to detect the participants opinions regarding available CGM systems and the future development of this systems. The interviewers has prepared questions beforehand and leads the discussion with these in mind during the whole process.

The interview is set with Erin Andersson (Brain Traﬃc) rules in mind, where the key for the interviewers are to truly listen to the participants to understand their needs [20, pp. 72]. By using open-ended questions the participants expounds their answers more widely instead of answering yes/no. They do not try to ﬁll the silent moments but instead give

Exploring Prototyping Validating

Activities 1. Semi-Structured Interview  2 participants  2. First Survey  111 participants Activities 3. Participatory Design  2 participants  4. Closed Card-Sorting  5 participants  5. Prototyping Activities 6. Test of Prototype  15 participants  7. Second Survey  15 participants  8. SUS Score  84%

Phase 1 Phase 2 Phase 3

Method Visualization 1: Outlines the diﬀerent phases and methods of the study.

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Answers

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space for the participants to think and collect their thoughts, and asks lighter/silly questions to create space to encourage the full truth to be told [20, pp. 72].

As a second part of the interviews, the participants is asked to use their respective system as they do on a daily basis to display how they navigate their product. The interviewers performs a moderated usability test where a set of tasks is set up so that the participants can show and explain how they interact with their products. For example, how they measure their glucose, how they navigate, and how they use the information that the CGM system provides to manually use their pump. They are asked to think out loud to enhance to the opportunity of catching how they truly feel [19, pp. 53]. Usability tests are eﬀective to use while working to identify design errors in navigation and misunderstandings to other details [21, pp. 28].

2.2.2 Method for the First Survey

The first survey is conducted with the purpose to get an insight of how diabetics in Sweden feel about the available CGM systems through collecting data concerning their background, preferences and requirements. The users is divided into two groups, one with people diagnosed with diabetes and one for parents with children diagnosed with diabetes. The reason for separating the groups is to investigate if the data is different depending on the group. The data is collected through an online form, where the questions are divided into different categories: multiple choice, short answer, and long answer questions.

The diﬀerent questions aims to categorize and research what kind of CGM system that they use, why they use it, if they have tried other systems that did not meet their needs and expectations. They get to write opinions regarding the associated mobile application, and improvements of their CGM system that they would like to have implemented in the future concerning design, hardware and software.

The long and short answer questions is more general to let the user answer the questions with explanations of what they think is most important to tell. The questions is asked with the goal to fill the research gap and answer the research question based on how their experience of available CGM systems are today. They are conceived through an iterative process of analyzing, gathering, and transforming data as the answer to the questions is the scope of the first phase of the research [22, pp. 15]. After collecting the participants’ answers, the data is analyzed with the goal to interpret and understand the user-needs. In an iterative process the results will get more advanced as the data is categorized and grouped. The full story of the data is most likely not visible at the first look but becomes more visible after transforming [22, pp. 16].

2.2.3 Method for the Prototype

After conducting and analyzing the data from the interview and the ﬁrst survey, a prototype is created. The information is categorized with headlines and sub-headlines through closed card sorting, a powerful technique both in qualitative and quantitative measurements. This technique is mainly used to build structures and study the user’s thoughts concerning how the navigation and information should be built [21, pp. 28].

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After conducting the closed card sorting, the second phase is initiated and the prototype is created. Prototyping is a fundamental technique which includes iterative user involvement, participation, testing, and validation in a earlier stage. The user input begins in a early stage, which brings their inﬂuence and thoughts towards the product while designing and creating it [23, pp. 143].

Design choices in regards to icons, titles, diagrams e.g. is made according to the information that the interview and ﬁrst survey resulted in, combined with standards for creating the best user experience.

2.2.4 Method for the Second Survey

A second survey is sent out along with a link to the prototype. The participants is asked to interact with the diﬀerent features for 5 - 10 minutes to determine how they feel about the navigation structure and overall user experience. After doing so, they are asked to move on to answer the questions in the second survey.

There are two different types of questions, three multiple choice questions where the participants get to compare the prototype with their currently used CGM system: “How do you perceive navigating to find the different features in your current product versus the prototype”, “How do you perceive the naming, information and icons is presented in your currently used product versus the prototype”, and “How do perceive using your current product versus the prototype”. This is five-scale questions where the options are ranged from “My current product is much better than the prototype” to “The prototype is much better than my current product”. These questions is constructed with the goal to get a quick and clear view if the prototype meets the goals that was collected in the first phase [18, pp. 56].

The second part of the questionnaire is a System Usability Score (SUS), which is a widely used tool to determine the usability of the product, in this case the prototype [19, pp. 137]. It consists of 10 statements where the participant gets to rate their opinions of the prototype on a ﬁve-scale where 1 is ”Don’t agree” and 5 ”Totally agree”. Half of the statements are positive, half of the statements are negative.

After collecting the answers, they will be analyzed and redesigned into a percentage, where 100% is equal to a perfect score [19, pp. 137]. Researchers suggest that the perception of the SUS answers should be: <50 is not acceptable, 50-70 is marginal, and >70 is acceptable [19, pp. 138].

2.3 Selection of Users

As the goal of the study is to analyze the user-needs, a constraint is made to only select people that use a CGM system, either for themselves or that their children use it. The importance of selecting the participants that are most representative for this study’s goal is major [19, pp. 58].

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The participants of the semi-structured interview are both people diagnosed with type 1 diabetes. One of the participants also have children with type 1 diabetes.

The participants of the study was sorted into diﬀerent groups depending on what CGM system that they currently use. The participants are found through various type 1 diabetic communities or associations, such as ”Diabetesförbundet Skåne Län”.

2.4 Materials Used

The material used in this study is:

1. Google Forms, to create and send out the online surveys to the participants. 2. The surveys is transformed into an Excel-ﬁle to enhance readability when analyzed. 3. The interview is recorded with Quicktime Player.

4. JustInMind is used to develop the prototype. This is a tool that is used to create clickable wireframes without real functionality. 

2.5 Ethical Considerations

This study examines three diﬀerent CGM systems available on the Swedish market. Due to ethical considerations the products will remain anonymous throughout the study and will be referred to as Product A, B and C. The product, or the companies behind the product, is irrelevant to the result because this study aims to examine future developments of the CGM system.

The participants of the interview is informed concerning the recording and made an oral consent to it. They are also informed that they will be anonymous in the study and that no personal information will be published. The participants are more than willing to participate, as they feel that research in this ﬁeld is important for them. They are compensated with coﬀee and cake while participating in the interview.

The participants of the surveys is informed before answering the online form that it is anonymous to participate. The last question describes what future progress the study will have, and if they wish to participate, they can leave their email. This question is voluntary to answer.

Information such as name, age, CGM system they use, residence, e.g. is left out as a result of this in the study.

3. Result

This section covers the outcome from the different methods used in this study, with the goal to find out what people diagnosed with type 1 diabetes requires in future CGM systems. This chapter outlines the result of the semi-structured interviews, the first survey, the prototype, the second survey and validation phase which is presented in different graphs and tables.

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3.1 Result of the Semi-Structured Interviews

After conducting and retrieving data from the ﬁrst survey, a semi-structured interview was performed with two participants, both diagnosed with type 1 diabetes. One of the participants was also a parent to a child diagnosed with type 1 diabetes. The purpose of the interviews was to get more speciﬁc insight of the disease and the user-needs in the system used to help their daily life.

A set of questions was created before the interview, which the interviewers made sure was asked. During the interview, the participants highlighted that they would like a product that works as a system of systems and the lack of good user experience in currently used systems. They were speciﬁcally discussing how they felt uncomfortable exhibiting their disease at all times, and that they had to do clothing decisions based on the fact that their pump and sensor needs to be accessible but also able to cover. In regards to the user experience, the participants felt uneasy to leave children with type 1 diabetes alone with other people that are unexperienced with these products, as the information is hard to understand and comprehend.

3.2 Result of the First Survey

To retrieve and access data concerning how users of the different CGM systems feel regarding the available products, a survey was created and sent out to different diabetic communities. 111 replies were collected from two different target groups, people diagnosed with type 1 diabetes and parents of children diagnosed with type 1 diabetes. The data that was collected was processed and gone through thoroughly to make sense of the participants answers. The data was analyzed and structured into diagrams that contains: “Which product they use”, “Why they use that product”, “Their opinion of the product they are using” and “What could be improved”.

After that the information was sorted and analyzed again. The data was labeled and sorted to broader categories which resulted in the following:

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Table 2: Outlines the result of the ﬁrst survey.

People diagnosed with type 1 diabetes Parents to children with type 1 diabetes

Question 1: What System do you use:

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The results of the “why part”, show that 39% of grownups and 62% of children use the product because of the software. 55% of grownups and 35% of children received their system through recommendation by either their hospital or likewise. Only 6% of grownups and 4% of children use the product they have because of the hardware.

The participants generally had a lot to say about the application of the product they are using. 38% grownups and 41% of the children was somewhat satisﬁed with the application. Which leaves 62% of the grownups and 59% of the children to be not satisﬁed with the product that they use. When the participants were asked what could be

Question 3: Opinions of mobile application:

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better in the products 41% of the grownups and 50% of the children thought that the user experience needed improvement. While 37 % of both the grownups and the children feel like the diﬀerent systems that they use could be better integrated in terms of a system of systems. And 23% of the grownups and 13% of the children wanted improvements in the hardware.

The citations below was collected in the ﬁrst survey and is kept in its raw form, which means that the data is not yet analyzed, categorized or labeled. The data were kept in mind while going into the next phase of this study.

P1 - “Since I now live alone, after my companion died, I would really like an alarm function, especially at night time. My fear is to not wake up in the morning due to low blood sugar during the night. I know that there are products on the market with the alarm function, my request to get one was however denied due to a money issue in the region” P2 - “Interactions with mobile phone. I can only see my values in the pump and I want to be able to give insulin through my iPhone.”

P3 - “The ability to control every function in my mobile phone, even giving insulin. Or maybe a smaller device, in a watch or something that you can keep in your wallet.”

P4 - ”It would be great to be able to see the battery status of the pump.”

P5 - ”The possibility to see the history of the curve, so that I can learn about my blood glucose trends.”

After analyzing the results the data were put into broader categories, user experience, hardware and system of systems. These categories represents the three main areas where the participants wanted changes or improvements. To explore if there were any differences in the results provided by people diagnosed with type 1 diabetes and parents to children diagnosed with type 1 diabetes, these groups were in the first survey kept apart. But because the result didn’t indicate any crucial differences, these groups later became one group, and not two separate ones.

3.3 Result of the Prototype

The prototype was created based on the analyzed data collected from the end users in the interview and first survey. Due to time constraints, there was no possibility of making a larger card-sorting with more participants with different technical background. Therefore the choice was made to perform a closed card-sorting with five students from the Information Architecture Program at Malmoe University.. The aim was to set the headlines and create the structure of the navigation. The work was done in an iterative process, where the participants of the semi-structured interview tested and commented on the design and features multiple times to ensure that the finished version would meet their expectations. A decision was made to create the prototype in Swedish, to ensure that the users would understand the meaning of the different features. Below is the different pages of the prototype is presented:

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To avoid leaving the users in a paradox of choice, the navigation was structured to have less categories, as too many choices can leave the user to not take any decisions at all and feeling that the prototype is hard to use [21, pp. 59].

Design choices were made to minimize unnecessary errors, where free-form text entry was avoided, and instead let the user choose between diﬀerent selections [21, pp. 127]. As the screen has limited space, it is profound that the design of the prototype uses up space thoughtfully. Non-essential information was repositioned to enable this [21, pp. 128]. The prototype was clickable wireframes of an IOS application, where navigation structure and user experience was the main focus. The prototype could be opened both in the browser, smartphones and tablets. While designing, a choice was made to include diﬀerent features supporting a system of system as the participants of the survey desired it. For example by being able to control the pump and sensor through the mobile application.

3.4 Result of Second Survey

When the prototype was completed a second survey was sent out alongside with instructions, information, and a link to the prototype. The participants consisted of the same people that attended the ﬁrst phase of interview and ﬁrst survey. They were asked

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to navigate and test the application for 5 - 10 minutes and then to continue with the questionnaire. There were 15 replies to the second survey. The ﬁrst part of the survey, where the participants got to compare their currently used product with the prototype of this study resulted in:

Table 3: Outlines the result of the second survey.

Q1: What product do you/your child use:

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The second part of the survey covered the SUS questions, where the participants got to rank their liking/disliking of the product. The SUS calculation is performed by subtracting 1 from the score on each of the odd numbered questions and subtracting the scored value from 5 for each of the even numbered questions. Then take the new values and add up the total score. Multiply this score with 2.5 and divide by the total number of participants, in this case, 15 [19, pp.108]. This resulted in:

Q3: Perceive the naming, information and icons is presented in your currently used product versus the prototype:

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Table 4: Outlines the questions on the System Usability Scale

Table 5: Outlines the result of the System Usability Scale (SUS)

The SUS was calculated accordingly which resulted in a score of 84% which is above accepted [19, pp.138].

System Usability Scale Questions

1 I think that I would like to use this system frequently.

2 I found the system unnecessarily complex.

3 I thought the system was easy to use.

4 I think that I would need the support of a technical person to be able to use this system.

5 I found the various functions in this system were well integrated.

6 I thought there was too much inconsistency in this system.

7 I would imagine that most people would learn to use this system very quickly.

8 I found the system very cumbersome to use.

9 I felt very conﬁdent using the system.

10 I needed to learn a lot of things before I could get going with this system.

P# Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Q10 Score P1 5 1 5 1 5 1 5 1 5 1 100,0 P2 3 1 5 1 4 3 5 1 4 1 85,0 P3 4 2 4 1 3 3 4 3 3 2 67,5 P4 5 1 5 1 5 1 5 1 5 1 100,0 P5 3 1 3 1 1 5 3 1 3 1 60,0 P6 4 1 5 1 5 1 5 1 4 1 95,0 P7 3 1 5 1 5 1 5 1 5 1 95,0 P8 4 2 5 1 4 3 5 1 4 1 85,0 P9 1 2 3 2 1 1 3 4 2 3 45,0 P10 5 3 5 1 5 1 5 1 3 1 90,0 P11 5 1 5 1 4 2 5 1 4 2 90,0 P12 4 1 5 2 5 1 5 1 5 1 95,0 P13 2 2 3 2 3 3 3 2 2 3 52,5 P14 3 1 5 1 5 1 5 1 5 1 95,0 P15 5 1 5 1 5 1 5 1 5 1 100,0 Total 1255 /15 participants = 84%

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4. Discussion

The following chapter covers a discussion regarding CGM systems for people diagnosed with type 1 diabetes in Sweden. A qualitative perspective with semi-structured interviews and a quantitative perspective with two diﬀerent surveys is used to both understand the research ﬁeld and to validate the result of this study. The goal of this study is to explore what people diagnosed with type 1 diabetes feel about their currently used CGM systems and what they would desire in future systems in regards to user experience.

The semi-structured interviews and ﬁrst survey answers the ﬁrst research question and based on the results a prototype is developed with participatory design and closed card-sorting. The design choices and user experience in the prototype are then validated by a second survey where the second research question is answered.

This section discusses the importance of user experience, resources in systems used within healthcare and self-management care to help support patients in their daily life. The design choices are brought up to attention. Furthermore, the discussion covers the anonymity of both the participants and the CGM systems that they use. And also if the result would be diﬀerent if this ethical consideration was not made. The discussion also covers the fact that there were some neutral answers due to the validation of the prototype, and why this option was presented. At last, this section covers a discussion about the technical feasibility, as this study solely covers the design part of an interface and not the technical functions behind it.

4.1 Addressing the Research Gap

Up until this point there is not much research on the user experience in CGM systems. This study attempts to ﬁll that research gap.

This study is of great signiﬁcance because of the large number of participants, a total of 118. 2 who participated in semi-structured interviews, 111 who participated in the ﬁrst survey, 5 who participated in the closed card-sorting, and 15 of the 111 participated in the validation of the prototype. The same study with less participants may not have had the same value.

To answer research question 1, the first stage was to get a better understand of diabetes in general and how patients use different CGM systems. Through semi-structured interviews a good foundation to what could be used in the first survey was gathered. In the early stages of this study people diagnosed with type 1 diabetes and parents of children diagnosed with type 1 diabetes was separated with the goal to explore if there were any major differences of opinions. The conclusion was that both groups feel somewhat the same, there is no major differences. Therefore these groups later became one group, and not two separate ones.

The results of this study shows that the participants feel that the user experience (41% of the people diagnosed with type 1 diabetes and 50% of the parents of children diagnosed

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with type 1 diabetes) of the CGM systems needs the most improvement, but would also appreciate improvement in terms of a system of system (23% of the people diagnosed with type 1 diabetes and 13% of the parents of children diagnosed with type 1 diabetes) and in the hardware (37% of the people diagnosed with type 1 diabetes and 37% of the parents of children diagnosed with type 1 diabetes). Therefore it was a natural decision to focus on the user experience part of CGM systems and also because it is relevant for the authors education.

To answer research question 2, the validation part (phase 3) contained a comparison between their currently used product versus the prototype developed in this study. The results indicates that 47% of the participants feel that the prototype is better or much better in navigation structure, 40% is neutral and 13% feel that their currently used product is better.

In terms of naming and icons presentation 53% feel that the prototype is better or much better, 27% is neutral and 20% think that their currently used product is better or much better.

46% perceive that the prototype is better or much better to use, 40% is neutral and 14% feel that their currently used product is better or much better.

When adding up these percentages to get an overview of the total score the result is:

4.2 Discussing the Results of this Study

The conclusion is that almost half of all the participants like the prototype better. This indicates that due to design choices made, the prototype gives the user a better user experience for most participants. One participant stated:

P6: - “Super nice! Just what we need. Simple, clear, easy to navigate and to do personal settings.”

Even though it was explained that the prototype was not a completed product just a mockup of how it could look, one participant commented:

P7: - “The application does not feel completed enough to do a justiﬁed judgement.”

Question Prefers Prototype Neutral Prefers Current product

Q2 47 % 40 % 13 %

Q3 53 % 27 % 20 %

Q4 46 % 40 % 14 %

Total 146/3 = 48,7 % 107/3 = 35,7 % 47/3 = 15,7 %

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Which states that some participants did not understand that the purpose was to propose a new navigation structure and an attempt to present information in a more user friendly way.

The choice of letting the end users compare their currently used product with the prototype was made. The participants got to answer on a ﬁve scale if they liked their currently used product or the prototype developed in this study better. To avoid a bias study, a neutral option was available. This option was to prevent that any participant had to select an option that they didn’t feel was accurate. The reason for the number of neutral answers could be that the participants didn’t know if this solution would be feasible to develop.

P8: - “The prototype looks promising but how would it technically work?”

Furthermore, some participants may have selected the neutral option because they are used to how their currently used product looks and works. Due to the severity of their disease, some participants may be restrictive to try new products if their currently used product is somewhat satisfying.

Some participants still thought that their currently used product works better for them but also states:

P9: - “The prototype is still new and I’m not used to it and thereby it loses compare to my current one.”

This shows that some people are not comfortable with changing to a new product if their currently used product works somewhat satisfying. To get all people to want to use the prototype it would probably take more time and resources to create an application that is fully developed.

The participants were also asked to fill out a form of pre-determined questions according to SUS. The reason for adding this was to get a total evaluation of the prototype and not to compare it to their currently used product. When the participants answered these five scale questions, the result showed that the usability of the prototype confirmed that the score was 84% which is over average. This confirms that the prototype still got a great score, even though some participants wanted a fully developed application.

4.3 Design Choices

Because of the results of the semi-structured interviews and the ﬁrst survey where the information that is necessary for diabetes patients is brought to attention the choice of labelling through closed card-sorting was made. Perception is bias where the experience of the user in regards of the participant's experience, their current context and their goals [24, pp.1] is already set in the means that the current CGM systems use speciﬁc terms. Therefore familiar frames were used to support the user experience in that given situation [24, pp. 3].

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To avoid ambiguity when designing information systems there should be testing to verify that the end users interpret the information in the same way. Or in the case where users have different experiences, for example, different CGM systems, ambiguity can be unavoidable. In these cases, it is important to rely on standards and conventions to maximize the understanding of the system [24, pp. 12]. When relying on standards and conventions there is a much greater chance of being consistent with the design of the user-interface. By using the same color, text fonts, and so on the consistency allows the users to spot and recognize patterns and the way the user-interface is built [24, pp. 12]. The end users of CGM systems mostly have the same goal, to manage their disease in a correct manner, and the designer should understand these goals to be able to create the best user experience for the users. The designer needs to ensure that at every point in an interaction, the user needs to be able to find the information or perform the task they set out for [24, pp. 12].

The prototype in this study is designed with the different gestalt laws in mind. The principle of proximity refers to the distance between objects and how this affects the user's perception of how the different objects relate to each other. For example, in the main page (picture 2) the different buttons are aligned with the same amount of space between them to ensure that the user understands that these are different categories [24, pp. 14]. Due to the gestalt law of similarity, which means the similarities of objects, the categories are designed to look similar to appear grouped. For example, in the category insulin (picture 6), the three buttons are all connected to insulin but have different tasks [24, pp. 16]. In regards to the law of continuity, the active curve (picture 3) and curve history (picture 10) enables the user to see the actual data and fill in the missing data so that they perceive the whole object. By doing this, the user can look at previous blood sugar curve pattern, learn from their behaviour and habits to get a better understanding and to predict future patterns [24, pp. 18]. The common fate law state that objects are perceived as related or grouped, for instance, active curve (picture 3), active curve notification (picture 4), active curve low value (picture 5) and curve history (picture 10) all move together because of its proximity and similarity [24, pp. 24]. All of these gestalt laws work best together, not in isolation. It’s the wholesome picture that determines the experience for the user [24, pp. 24].

4.4 Discussion of Decisions and Constraints

In the early stage of this study, an interesting aspect would be to explore whether or not the age of the participants would matter in the sense of how they interpret the interface. Would it be possible to see a correlation between how various age groups perceive the user experience of both their currently used product and the prototype developed in this study. As users in various age groups could have different experience with managing their disease, it could be interesting to explore if the results would differ in the different age groups. This aspect was thought upon too late and therefore didn't take place in this study.

Another matter that could have been managed diﬀerently would be to develop a ﬁnished application with working functionalities. This may have changed the neutral answers of the second survey to a even better result in regards of how the participants felt about the

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prototype. By doing this, the survey may have been even more credible in a sense of how companies can implement better user experience of their products. If the study had been in collaboration with one of the CGM developing companies, it may have been possible that the manufacturers would continue to develop a solution that is better suited for all diabetic patients. It would be interesting to see how the functionalities of a system of system could be developed and perceived by the end users.

In terms of design, if more resources were available the design of the prototype could be fully develop and tested with the end users. To avoid any ambiguity for the participants, user testing could have been conducted with the end users to see what possibly could have been designed diﬀerently to enhance the gestalt laws even more. This phase would be more in depth if the possibility of doing iterative releases and testing would be manageable. It would be interesting to involve the end users even more in the process, and to have a real life observation of the prototype. The prototype may have looked somewhat diﬀerent after this iterative process, but due to time constraints this was not possible in this study.

As vision loss or even blindness is one possible consequence of improper management of diabetes, it would be of great value to explore the possibilities of making the prototype available for the aﬀected people as well. User testing with this group of people would ensure that even patients with these kind of disabilities would be able to manage their disease properly through a CGM system. The study would have had a broader contribution if this would have been included/considered

Due to ethical consideration, no information concerning the participants or products that they use is mentioned in the study. It is possible that the outcome of this study would be diﬀerent if this constraint was not made. The participation may have altered and the participants may not have answered as honestly as they did, if they knew that their answers wouldn’t be anonymous. Because of the dependency of the diabetes products that this study examines, the participants appreciated that a anonymity constraint was made. Knowing that their opinions about their currently used product were protected, the participants were more than happy to contribute.

Diabetes patients have to carry multiple tools to manage their disease today. In previous studies, and a lot of the participants in this study, requests a system of the system. But still, there is no such solution developed on the Swedish market today.

While this study focuses on the user experience and user interface part of CGM systems, and not the features and functionalities behind a system of system solution, it is still relevant to ask why this solution is not available. The development of this kind of systems in other ﬁelds, for example the computer science community, is more advanced and many of these systems have better user experience and user interfaces than healthcare applications. Given the technical possibilities available today, this type of solution is not out of reach. But a possible reason that this is not developed yet, is due to the importance of making this system reliable because people's lives can depend on it. It is also possible that self-management tools for diabetes patients is not a priority when dividing resources within healthcare. The area of healthcare applications still has a long way to go. This study can be used to continue exploring these possibilities in future research.

Exploring the User Experience in Continuous Glucose Monitoring Systems