Design Dimensions of Ambient Information Systems to Facilitate the Development of AAL Environments

Marcela D. Rodríguez, Juan Pablo García-Vázquez, Ángel G. Andrade Master and Doctoral program on Science and Engineering (MyDCI), School of Engineering, Campus Mexicali

Autonomous University of Baja California (UABC), Mexicali, México +52 686 5664270

{marcerod,pablo.garcia,aandrade}@uabc.edu.mx

ABSTRACT

AAL (Ambient Assisted Living) aims to extend the time elderly can live in their home environment by assisting them in carrying out activities of daily living (ADLs). Designers of AAL must not only consider the needs and problems that elders face when carrying out their ADLs, but that elders are characterized by presenting a natural cognitive decline, their attention levels are diminished and that they may consider that new technologies are complex to use. Considering these characteristics of elders, we propose Ambient Information Systems (AIS) as the appropriate technology to assist elders, since they are aesthetically pleasing applications which provide users with abstract representations of valued information. The aim of this work was to identify the design issues that should be addressed for developing AIS that effectively assist elderly with their ADLs. To reach this end, we designed mobile and embedded AIS that help elderly to manage their medication, since it is one of the critical ADLs for enabling “ageing in place”. As a result of designing AIS, we identified a set of design attributes that were validated and extended through inspection evaluations with Computer Science and Health professionals. Categories and Subject Descriptors H.5.2 [Information Interfaces and Presentation]: User Interfaces – Evaluation/methodology, Style guides.

General Terms Design, Human Factors.

Keywords Ambient Information Systems – Ambient Assisted Living - Design Dimensions – Inspection Evaluation - Elderly.

1. INTRODUCTION AAL (Ambient Assisted Living) aims to extend the time older people can live in their home environment by assisting them in

carrying out activities of daily living (ADLs) [1]. To reach this end, designers must not only consider the needs and problems that elders face when carrying out their ADLs, but that some elders are characterized by presenting certain level of cognitive decline, their attention levels are diminished and that they may consider that new technologies are complex to use. Considering these characteristics of elders, we propose Ambient Information Systems (AIS) as the appropriate technology to assist elders, since they are aesthetically pleasing applications which provide users with valued information that is easy to comprehend, through subtle ambient changes, i.e. in light, sound or movement [2,3]. AIS can work as i) Peripheral Displays if they are out of the focus of attention, since they allow users to monitor information without distracting or burdening them; as ii) Ambient Displays that make use of the entire physical environment as an interface to digital information; thus, the term Ambient Display emphasizes the physicality or tangibility of the displays which transmit information often in the users periphery [4]; and finally as iii) Notification Systems if they are used in a divided-attention, multitasking situation, attempting to deliver current and valued information without introducing unwanted interruption to a primary task [5]. Thus, AIS should be designed with the goal of requiring minimal attention and cognitive effort from the user by presenting information that is easy to comprehend. Furthermore, users should perceive AIS as naturally integrated into their environments.

The aim of this work is to identify the design issues that should be addressed for developing AIS that effectively assist the elderly with their ADLs. To reach this end, we designed mobile and embedded AIS that help elderly to manage their medication, since it is one of the critical ADLs for enabling “ageing in place”. It has been identified that remembering to take medication, at the right time and in the right order and doses, improve health status and functionality. Persons who are over 65 years have higher rates of non-adherence, and those living alone who take more than three medications are prone to medication errors[6]. It is estimated that 26% to 59% of older adults have lower drugs compliance due to cognitive and perceptual changes that co-occur with age, make them susceptible to medication errors such as forgetting to take their drugs, taking incorrect doses, or to terminate drug-taking prematurely if they feel better [6]. As a result of designing AIS to assist elders to take appropriately their medicines, we identified a set of design attributes that were validated and extended through inspection evaluations with Computer Science and Health professionals.

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The rest of the paper is organized as follows: Section 2 presents work related to AIS designed for supporting the elders’ well being, and to taxonomies of design attributes of AIS. Section 3 presents de AIS designed for aiding elders to maedicate. Section 4 explains the design dimensions of AIS that we identified for supporting the independent living of older adults. Section 5 presents the results of evaluating the proposed AIS. Finally, section 6 presents the conclusions and future work.

2. RELATED WORK To our knowledge, there are no design principles or guidelines for developing AIS for older adults, such as those found for designing web based interactive systems [7]. Even though several research works have identified design dimensions of AIS from the analysis of existing ambient displays and notification displays, there is a lack of understanding about how these attributes should be adapted for designing effective AIS to assist the elderly. Matthews et al provide a toolkit to facilitate developers to address key attributes of peripheral displays to appropriately manage users attention to present them important information [3]. Based on the concept of what an Ambient Information System is, other works provide taxonomies of design attributes, which are useful tools for categorizing existing AIS developments in order to identify trends on this area [8], and which can be thought of as design choices or questions that AIS developers must answer [2]. These key attributes and taxonomies mainly describe different modalities that AIS can use for grasping the appropriate amount of users attention and for representing critical and non-critical information. For instance, Abstraction refers to encoding data to allow users to easily comprehend and monitor information [3,8]. In this same direction, Representation Fidelity refers to representing information by using signs of the Semiotics Language, and Information Capacity refers to the number of discrete information sources represented by the AIS, which can be measured as low, medium and high [2]. The term Notification Level is the degree in which the system attracts the user attention. A higher notification level is used to display more critical information in a way that grabs the user attention; while a lower notification level correspond to non-critical information which is displayed in a way that allows a user to monitor the system occasionally or peripherally [2,3,8]. The above-mentioned design dimensions provide valued information that enables designers to get a deeper understanding of the scope and limitations of Ambient Information Systems. However, they do not provide guidelines that help to identify how to apply and combine these design

attributes for supporting users activities of a particular context of use, such as elders managing their medication.

For supporting medication management, pillboxes have been digitally augmented to provide reminders, i.e. by presenting pictures of the drugs to take on a Personal Digital Assistant attached to the pillbox [9]. In the design of these personal medication systems, one of the aspects taken into account was the fact that in some countries, pharmacists dispense the total amount of pills prescribed by the physician, and they may load the pills into the elders’ personal medication system. However, in developing countries like Mexico, this kind of support service is not available. We think that elders need systems that not only assist them to medicate correctly, but encourage them to follow their medication routine and not stop it because they do not have symptoms anymore. In the following section we present the AIS designed for supporting different aspects of older adults medication.

3. DESIGN OF AMBIENT INFORMATION SYSTEMS We designed AIS embedded in different objects of the elders’ environment in order to enhance some of the elderly’s strategies they use for avoiding the common and relevant medication problems they may face. These strategies were identified from a case study that consisted of interviewing 17 older adults, as it is reported in [10].

3.1 Context Aware Representation of Elderly Medication (CARE-Me) To encourage the medication compliance of the elders, we designed CARE-Me with the aim of making them aware of the importance of not terminating drug-taking prematurely because they do not have symptoms anymore, or because medication side effects. CARE-Me can be presented in glanceable devices, such as a portrait (see fig. 1a). It presents a virtual cage of birds with the aim of raising elders’ consciousness about how they have to take the responsibility for caring for their own health, in a similar way that they gladly take care of their pets. The behavior of the birds in the virtual cage, symbolizes the repercussions on the elders health of taking or not taking their medications in the last four weeks. According to our case study results, elders get their medicines monthly when they visit their doctor [10]. Thus, we decided to represent the elder’s medication adherence with four parakeets associated with each week of the month. As presented

Figure 1. CARE-Me system: a) CARE-Me embedded in a portrait, a common object of a home; b) CARE Me representing an appropriate compliance of the elder’s medication; c) CARE-Me representing an inappropriate compliance of the medication.

in figure 1b) and c), the bird associated with the current medicating week is in the nest, and the birds on the tree represent the last three medicating weeks. The daily adherence of the elder contributes to the growth of the parakeets. If the daily doses of each medicine are taken correctly by the elder during the current week, the parakeet in the nest increments its size according to defined levels of growth. When the current medication week ends, the parakeet flies to the tree and a bird egg appears on the nest to represent the beginning of the next medication week.

3.2 Remind elders to Medicate (Remind-Me) Remind-Me consists of mobile phones that provide timely auditory reminders for taking medicines. The audible notification consists of a parakeet whistle, which is associated with the metaphor of caring for pets used to persuade elders of the importance of medicating. When an auditory reminder is emitted, a visual notification is presented on the mobile device to provide elders with critical information of the medicines to take, i.e. Remind-Me in figure 2a indicates to take one pill of Enalapril for controlling the elder blood pressure; this health problem is represented by an image of a food highly associated with it.

3.3 Geometric User Interfaces to Display aids for the Elderly when Medicating (GUIDE-Me) GUIDE-Me has the aim of assisting elders when medicating by providing ambient aids. As presented in figure 2b, it is a set of geometric user interfaces tied to each medicine of the elder. The number of sides on each geometric user interface indicates the number of times per day (frequency) that the elder needs to take her medicines. For instance, circular interfaces are associated with the medicines that have to be taken once a day, and triangular interfaces are associated with medicines that have to be taken three times per day. To indicate to the elder which medicines she has to take, the sides of the geometric user interfaces are highlighted. The number of highlighted sides corresponds to the medicine compliance frequency. For instance, figure 2b shows a medicine with a square user interface with two sides highlighted to indicate that it is the second dose of the day of a total of four that she needs to take daily. The highlighted sides are turned off when she takes the medicine or after a pre-established time (i.e. 30 minutes later). In addition, the geometric user interfaces provide elders with relevant information for medicating appropriately, such as the doses to take, and the health problem

addressed by the medicine, which is represented by an image highly associated with it.

3.4 Usage Scenario To illustrate how we expect the designed AIS assist elders with their medication activity, we present the following scenario: “While Mrs. Anna is reading a novel before going to bed, she hears the whistle of her parakeets emitted by the Remind-Me system, which alerts her of taking her medicines. When Mrs. Anna approaches her medicines, she perceives that GUIDE-Me is highlighting the medicines that she needs to take. Ms. Anna takes the bottle with the highlighted circular interface containing the medicine for controlling her cholesterol that has to be taken once a day. Then, she takes the medicine with the moon-shaped interface, as she identifies that it is the recently prescribed medicine for controlling her blood pressure, she pays special attention to identify how many pills she must take. And finally, she takes her medicine with a triangular interface with two highlighted sides, which indicates that the second dose of the medicine for controlling her blood sugar levels should be taken. Latter, when Mrs. Anna is in her living room, she hears that one of her parakeet says her favorite phrase: “Periquito Curro” (most Mexicans teach parakeets to say this common phrase). So, she gets very happy, since this means she medicated correctly the last week. Then, Mrs. Anna sees CARE-Me and identifies that her parakeets on the tree have reached their maximum growth level, and that the parakeet on the nest is growing as expected”.

4. AIS DESIGN DIMENSIONS Designing AIS for addressing some of the problems faced by the elderly when medicating, enabled us to identify the design dimensions for developing AIS for elders which are summarized in table 1:

Strategy to assist. This design dimension enables AIS developers to identify the kind of support that the elderly may need for carrying out an ADL, and therefore, the purpose of the information to be presented to assist them. Based on our understanding of how elders medicate, it was identified that older adults need systems that:

- Remind them to execute an ADL in a timely way by providing ambient notifications that interrupt their current activity in order to call their attention to perform an ADL in a timely fashion.

Figure 2. a) Critical information presented to the elder, such as: the medicine name, an image associated with the health problem addressed by the medicine (i.e. blood pressure), doses to take (1 pill). b) GUIDE-Me system providing ambient aids for medicating.

- Guide elders by providing ambient aids to enable them to select the objects and or tools they need to perform their ADLs, such as taking the correct medicines. Additionally, the AIS should provide elders with critical information, i.e. the doses, purpose of the medicine and the frequency for taking it.

- Motivate elders to carry out their ADLs. For instance, the CARE-Me system was designed to motivate them to take their medication by persuading them of the importance of taking their medication appropriately and of not halting it. To reach this end, elders need to be aware of their activity compliance and receive rewards or positive stimulus as they are completing or carrying out their ADL appropriately.

Orientation of the activity. It defines how the system expects that elders act in order to complete an ADL. We consider that the AAL infrastructure must have context-aware mechanisms [10] to determine the state of the activity in order for the Ambient Information Systems to enable elders to change the current ADL state regarding its completeness. That is, Ambient Information Systems should enable a pending activity to go to the executed state, and then reach the completed state resulting thus, in AIS that:

- Demand to execute an activity. For instance, Remind-Me provides auditory notifications to help elders to initiate a pending activity, and GUIDE-Me provides ambient aids to help elders to appropriately complete their medication.

- Make elders aware about critical information. In order for accomplishing and successfully completing an activity, elders need to have at hand critical information, such as the doses and name of the medicine.

- Make elders aware about their behavior towards the activity. For instance, the CARE-Me system has this particular aim in order to encourage elders to carry on taking their pills.

Object target. A relevant design issue is deciding the appropriate physical object that may become an AIS. We identified that these

objects can be classified as Basic objects, which are those that elders currently use to perform an activity, i.e medicine containers and therefore, they are more prone to attract the elder’s attention when executing the activity. Thus, they are appropriate devices to present valued and critical information, such as alerts to prevent a risk associate with the activity, or instructions to complete it correctly. For instance, the GUIDE-Me system is attached to basic objects (medicine containers) to present the doses and frequency for taking medications. Complementary objects are those artifacts that are not currently used or necessary for the activity, but are located in the elders’ environment (such as ornamental artifacts), and can be digitally enhanced to assist elders in performing the activity. For instance, CARE-Me can be presented in a portrait located in the kitchen, in order for it to be frequently glanced at. Similarly, Remind-Me should be located in a mobile or wearable device in order for it to attract the elder’s attention to execute the activity.

Notification level. It is the degree to which system alerts are meant to interrupt users by making them aware of the importance of the information with the aim of encouraging them to carry out an activity [2]. To reach this end, designers should consider the elders’ cognitive ability to perceive stimulus from their environment. Elders are able to focus voluntarily on a sensorial stimulus to get relevant information, which is a main feature of selective attention. However, elders lose the ability to concentrate on more than one stimulus simultaneously to perform dual tasks, which is a main feature of divided attention. Thus, AIS should provide notification levels that grab the selective attention for presenting critical information for carrying out an activity. As presented in table 1, we identified several notification levels that have the aim of grabbing the selective attention. The Schedule interrupt level aims to prepare elders to mobilize to attention (alertness) with the aim of distracting them from their current activity in order to demand they perform a scheduled ADL; i.e. Remind-Me is embedded in a mobile device to deliver timely auditory notifications anywhere. Similarly, the Activity-aware interrupt attribute can be used when the elders need to be warned of an inappropriate action that may affect their well being or

Strategy to assist

Orientation of the activity Notification level Target object of AIS

Tuning of ambient information*

Remind Guide Motivate

Demand to execute an activity Make elders aware about critical information Make elders aware about their behavior towards the activity Reinforce the elders behavior towards the activity*

Schedule interrupt Activity-aware interrupt Orientative awareness Activity behavior awareness

Basic object Complementary object

Modality of notification Fidelity of information representation

 

Table 1. Design dimensions of AIS aim to support the elders ADL. Those marked with * were identified from the AIS evaluation results.

health, such as detecting that elders is taking more pills then the recommended (overmedicating). The Orientative awareness level, makes elders aware of how to carry out the activity by presenting relevant information, such as GUIDE-Me. AIS may also provide notification levels that work on the elders’ divided attention if they do not present critical information for example, the CARE-Me system provides representations of the elders medication adherence to encourage them to medicate. In this case, the Activity behavior awareness level has the aim of consuming some of the elders’ attention to make them aware of their activity performance or compliance.

5. EVALUATION We carried out an inspection review based on the feature inspection method [11] in which experts, with different backgrounds and level of expertise, checked if the ambient information systems conform with a set of features. In this inspection method the evaluator has simply look through the system whether the features on a checklist are available or not. Thus, the method is simpler than other inspection methods (i.e heuristic evaluations) since the evaluator does not have to use or develop any metrics while testing. Additionally, this method enabled us to collect qualitative and quantitative data to identify design issues of the AIS and to assess the design attributes we presented in Table 1. We designed a feature checklist based on the design principles for ambient displays proposed by Mankoff et al [12] and incorporated some of our proposed design dimensions that we considered were not directly validated with these design principles, such as the object target used for embedded the AIS. Even though this evaluation enabled us to identify a list of usability issues of the AIS [13], this paper has the purpose of reporting on the qualitative analysis that we carried out from the reviewers’ comments to validate the design attributes of AIS for assisting elders to manage their medication. Thus, evaluators assessed if the ambient information systems conform with the following desirable features of AIS designed for assisting elders: Presenting useful and relevant information (H1), Peripherality of the AIS (H2), Match between system and real world (H3), Sufficient information design (H4), Consistent and intuitive mapping (H5), Easy transition to more in-depth information (H6), Visibility of status (H7), Aesthetic and pleasing design (H8), Strategy to assist (H9), Object target of the AIS.

To obtain information that enabled us to evaluate if the AIS were appropriately design for assisting elders we selected evaluators which were experts on designing systems and on the domain of use of the proposed AIS. Thus, the evaluators were categorized as novice experts on usability who have knowledge about software development; advanced experts who are working specifically in projects related to the Human-Computer Interaction area; and domain experts who are specialists in areas different from Computer Science but their expertise is relevant to solve the target problem (health-care specialists). Thus, domain experts can be users representatives, since they know the elders’ needs and problems for medicating and for interacting with the proposed computer-based systems.

5.1 Evaluation Protocol Seventeen experts (17) participated in the evaluation: seven of them (7/17), who had a master degree or were graduate students in Computer Science, were categorized as novice experts (N); five (5/17) were advanced experts (E) since they were PhD students or researchers in Computer Science working in projects related in

HCI and Ubiquitous Computing; and finally, five (5/17) were medical doctors and researchers in Geriatrics who were categorized as domain experts (G). Each group participated in an evaluation session which consisted of a 10-minutes presentation of our motivation to design AIS that support the elders independent living; a 15-minutes presentation of the design of each AIS; then, participants individually proceeded to evaluate the AIS (30-40 minutes for each AIS) by specifying an acceptance level on each design feature with a 5 point-Likert scale ranging from -2 (“I completely disagree”) to 2 (“I completely agree”) and providing an explanation of their response. Finally, experts formed groups of 2 or 3 members to discuss during 15 minutes at least two of the design principles that they considered were the most difficult to evaluate for each AIS. We recorded these discussion sessions in order to be analyzed later.

a)

b)

c)

Figure 3. Results of evaluating a) CARe-Me, b) Remind-Me and c) GUIDE-Me.

5.2 Validation of AIS Design Dimensions To carry out the qualitative analysis, we analyzed the comments provided by the evaluators from the features that obtained an average less than 1 (“I agree”), which indicates a low degree of conformity.

• Notification systems with scheduled interrupts are appropriate to remind elders to execute an activity. Eleven (11/17) evaluators considered that the Remind-Me system is not a peripheral display since H2 gets an average of -0.17. However, participants commented that even though the system does interrupt elders’ current activity and aims to attract their attention, its design is appropriate to demand elders to timely execute an important activity.

• Mobile devices are complementary objects for providing timely notifications to elders. Feature (H3) regarding the AIS is in harmony with the elders environment, gets an average of 0.99 since four (4/17) of the advanced experts considered that mobile devices are not common objects used by elders at their homes. However, thirteen (13/17) participants stated that mobile devices are more appropriate to provide reminders for medicating, as elders can get used to take them anywhere. Additionally, even though evaluators considered Remind-Me has sufficient design information (H4 = 1.24). Nine (9/17) participants suggested that this mobile AIS should inform elders about the medication pre-conditions and restrictions, such as the order to take the medicines, if medicines should be taken after meals, and which medicines they have already taken or not.

• Basic objects should influence elders to execute an ADL’s action. According to the evaluation results of the GUIDE-Me system, it is not helpful to provide additional information regarding how to execute an ADL (such as the frequency for medicating, taken medicines). Thus, H4 (sufficient information design) got 0.84 and H6 (easy identification of multi-leveled information) got 0.32. All participants commented that the GUIDE-Me system presents too much information, that can be difficult to interpret. Consequently, H5 (consistent and intuitive mapping) got an average of -0.11. Finally, augmenting basic objects with additional and multi-level information results in non-aesthetical AIS; as evidence of this, the heuristic H8 (aesthetical design) got an average of 0.51. Ambient information systems embedded in basic objects should be designed to provide the necessary information to influence elders to carry out a specific action that is relevant to complete an ADL.

• Reinforce the elders’ behavior towards the activity*. As presented in table 1, this is an attribute we identify may enable elders to orientate to carry out the activity (Orientate the Activity design dimension). This attribute refers to provide information to enable elders to reinforce their learnability regarding of how to carry out a complex activity. Most of the evaluators (12/17) commented (which included all geriatric specialists) when evaluated the CARE-Me system, that it should provide elders with stylized representations of their daily medication and with additional information in order to reinforce the instructions elders have to follow for medicating. Additionally, feature (H4) that evaluates whether CARe-Me presents sufficient information design, got an average of 0.81 and H6 got an average of 0.52, which evaluates if it is easy to identify detailed information when the AIS provide multi-leveled information. Evaluators suggested that this device should inform elders about the medicines that have been taken as well as those that have not been taken, which may enable

them to identify some behavior patterns, such as forgetting to take a specific medicine on the same day. Geriatrics specialists emphasized that a daily reinforcement may enable elders to better comprehend their medication compliance. In this same direction, four geriatrics and one advanced experts (5/17) suggested to providing daily rewards instead of weekly. They suggested that the parakeets said phrases that congratulate the elders’ appropriate behavior or phrases that notify inappropriate behavior towards the activity.

• Tuning of ambient information*. Tuning the ambient information to elders’ perceptual characteristics was identified as a result of the evaluation. The adjustment should be carried out on the used Fidelity of information representation and Modality of notification [2]. The Representation of fidelity attribute refers to providing information that is easy to read and interpret “at glance”; to reach this end, designers should use semiotics language, such as iconic signs which have some similarity with the represented information object, i.e. metaphors, and indexical signs which are highly related to the information to communicate. The Modality of notification attribute refers to how information is presented to be perceived through any of the human senses, such as visual and auditory notification modalities. As evidence of the importance of tuning the ambient information of the system, we obtain evaluators feedback regarding the audible notification modality of Remind-Me and CARE-Me. Six (6/17) evaluators (which included all geriatric specialists) stated that the parakeet whistle may be unpleasant and not easily heard by some elders. Evaluators suggested using low frequency sounds for providing notifications, since the elders’ ability to hear simple tones shows reliable age declines. A discussion of two (2) advanced experts centered in that AIS should not be designed to be in highly harmony with the elders environment in order to avoid that elders stop of perceiving the ambient information that devices provide to assist them, in a similar way in which we stop of perceiving some of the sounds of our home environment, such as the meowing of a cat. Additionally, the geriatrics specialists suggested including the name of the elder in the rewards phrases which may have twofold advantages: to grasp the elders’ attentions and to open a trust linkage between the elder and her AIS.

6. CONCLUSIONS The design and evaluation process of these systems enabled us to identify the design dimensions of AIS proposed for supporting the elders’ independent living. This is a step toward proposing design guidelines for the development of AIS that support the independent living of the elderly. In order to identify the usability problems of the AIS, we carried out a formative evaluation by using heuristics (design criteria). The evaluation results also showed that novice evaluators focus on reporting usability problems on the interface, while expert evaluators provided more suggestions of how to improve the interfaces of AIS. However, both of them had difficulties in reporting problems related to the potential users’ (elderly) reactions when using the AIS, which were better identified by the non-usability experts who were geriatric specialists. The results obtained will enable us to carry out a summative evaluation, in which elderly will use the ambient information systems in order to prove their effectiveness. Thus, we will identify how much AIS improve the elders’ independent living, what makes one ambient information system more effective than another and, how well older adults learn to use them.

7. ACKNOWLEDGMENTS We thank to professors, researchers and students who participated in the evaluation and to CONACyT for the scholarship granted to Juan Pablo García-Vázquez.

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