AGENDA
- Every aspect of the hearing device — the appearance, the fit and feel and the signal processing — has to be right.
- Oticon Intiga provides a solid foundation to change the patient's preconceptions when they enter the process.
- Patients no longer have to "put up" with the side effects of newly fit hearing devices.
- Performance starts high and remains high right from Day 1.
- The sum total is to provide the user with devices that can be counted on over the years.
- Oticon makes it as easy as possible for the first-time user to accept Oticon Intiga as the path to better communication performance.
Fittings with first-time users are always at risk.
Addressing the First-Time User
It is a well recognized reality among hearing care professionals that fittings with first-time users are always at risk. The commitment of these patients entering the fitting process is often incomplete and any negative occurrence can quickly derail the fitting. If the fit or feel is not right, if newly amplified sound is unnatural or annoying, or if the process feels rushed and not focused on the agenda of the patient, the hearing instruments quickly may be returned and that patient may never again seek out hearing care. These patients have documented hearing loss, but their motivation to see the process of becoming a hearing device user to the finish may be weak. In order to maximize the chances that a fitting with a first-time user will ultimately be successful, the hearing care professional needs to do many things well. New patients need to be attracted into the process, all interactions with these patients need to be positive and the products that are provided must meet the high demands of new users.
Oticon Intiga is a new RITE solution by Oticon specifically designed to meet the high demands of first-time users. It is offered at three technology levels, Intiga 10, Intiga 8 and Intiga 6. It uses a new ergonomic case design and a new speaker and wire assembly. It is built on a miniaturized version of the RISE 2 digital platform and includes (in the Intiga 10) the advanced signal processing that has distinguished Oticon Agil Pro. Figure 1 provides the complete Oticon portfolio of products, demonstrating where the Oticon Intiga products fit in. They represent our Design products across the traditional categories of Essential, Advanced and Premium.
Every aspect of the device — the physical appearance, the fit and feel on the ear, the durability and the signal processing — has been designed specifically to maximize the likelihood of successful fittings with first-time users. In a companion paper (Schum, Weile & Behrens, 2011), we discuss the process of motivating first-time users to increase the chances of a successful fitting process. The focus of this paper is to describe the development of Intiga, with a specific focus on the details that are assumed to matter most to the first-time user.
Figure 1. The Oticon product portfolio.
In a recent large-scale international survey (Oticon/Decision Lab, 2010), 750 individuals who suspected that they had hearing loss, but as of yet had not obtained hearing devices, were asked which aspects they would rate highly if they were to obtain amplification. The top six reasons stated were (in order of occurrence):
- That they feel comfortable to wear
- That I understand speech clearly
- That they are discreet
- That I hear sounds the way I expect to
- That they are completely invisible
- That they are easy to handle
It is clear from these responses that first-time users are concerned about a variety of dimensions: not just performance, not just appearance. We believe that the agenda of the typical first-time user follows a specific order over time. At first, appearance and immediate sound experiences tend to dominate the initial exposure to amplification. Speech understanding performance in key situations becomes relevant once the patient has developed some minimal comfort level with the idea of using amplification.
Given the tentative nature of the patient commitment to the fitting process, negative experiences in any of these three domains can quickly demotivate the patient. Oticon Intiga was developed specifically with three important domains in mind: appearance, initial acceptance and performance in key listening situations. The overriding focus was in creating a new product that can bring acceptance and improved performance to new users very quickly. These patients often will not give the hearing care professional the full traditional 30-day trial period before deciding that amplification is not for them. Patients who raise their hand may talk themselves out of getting hearing instruments even before the trial listening experience. If the process moves to the point of a trial fitting, it is of the utmost importance that every aspect of the patient's initial experiences is positive.
As pointed out in the companion paper (Schum, Weile & Behrens, 2011), if potential new users are managed properly, they will have a positive attitude about the fitting process from day one. However, their expectations may not fully reflect the reality of using hearing instruments. They may not be prepared for the feel of devices on their head or the sounds of newly amplified signals. They also may be expecting immediately improved performance. If their expectations are not met, some of the lingering reluctance that they may have been feeling when they first entered the process may re-emerge. Again, it is essential that the products fit to these at-risk patients meet these high demands.
Traditionally, hearing care professionals tend to want to focus on the functional benefits of the newly fit hearing instruments right from the start. However, the patient's agenda may be different. The classic first-time user may first care about how the hearing instruments look, then on how new sounds sound and then later on how well they are performing. The products selected for the patient need to make sense based on this agenda. Oticon Intiga is specifically designed with this set of priorities in mind.
Appearance
A recent re-emerged trend in our field is to try to attract new users with the claim of "invisible" hearing devices. These deeply-seated, completely in-the-canal (CIC) devices offer the hope to new patients that no one will know that they are wearing amplification. The reality is that creating a totally invisible, canal-placed device is only possible for a minority of users. For those with ear canal size and geometry that is sufficient to accept these devices, patients may be surprised by the side effects of such fittings: occlusion and physical discomfort. For custom molded options, a deep ear canal impression is one of the first steps. Further, insertion and extraction of these devices is typically not a simple process. In many cases, the technology used in these very small devices does not represent state-of-the-art signal processing in our field. Connectivity is not possible. Basically, the cost to the patient of "invisible" hearing instruments is high.
Oticon Intiga offers a reasonable alternative to discreet technology, but without the side effects of deeply-seated canal devices. Upon first viewing, the patient may be surprised by the small size and ergonomic shape. Figure 2 shows the Oticon Intiga product compared to the outline of the Oticon miniRITE used with Oticon Agil, Oticon Acto and Oticon Ino. Oticon Intiga is 33% smaller. In the hand, the product is lightweight, which often will also surprise a new user who has an image when entering the process of traditional, large, heavy beige BTEs. Oticon Intiga's surface is clean and unbroken. Its naturally rounded shape follows the physical outline of the ear, achieving a close, comfortable fit, without a volume control or push buttons.
Figure 2. The size of Oticon Intiga compared to Oticon Agil miniRITE
Oticon Intiga also introduces a new RITE receiver shape (Figure 3), which is curved to follow the natural contour of the ear canal. The new speaker wire is thinner with a matte finish, further improving the discreetness of the hearing device when in place on the ear.
Figure 3. Close up of the new speaker unit.
Having the patient see the device in place on the ear is a key. The traditional expectation is that BTEs are highly visible. The combination of size, shape and available color palette allow for a level of discreetness that the patient may not expect. There is no doubt that some potential first-time users may be stuck on the idea that discreetness means deep in the ear canal. With Oticon Intiga, the reduced level of side effects along with the capability of having the full range of advanced features provides a solid foundation to work on changing this preconception that the patient may have when they enter the process.
Importantly, the product can be fit instantly, allowing for immediate demonstration when appropriate. There is no need to make a deep canal impression, perform a microscopic examination of the ear canal or wait for delivery. The patient can quickly and smoothly move from the pleasant surprise of the appearance to the initial listening experience. Getting to the point of listening early in the process can assist in changing the focus of the patient from the expectation or hope of an "invisible" solution in the ear canal to the realization that there are important sounds that now can be heard.
Initial Sound Experiences
The traditional viewpoint held by many hearing care professionals is that it takes time for the first-time user to get used to the sound of amplification (e.g., Citron, 2000; Dillon, 2001; Schweitzer, 1993). Although, historically, this notion is accurate, advances in the physical design of products and in the signal processing incorporated into advanced technology have made this viewpoint less accurate. In a recent pair of studies (Smart, Kreisman, Robinson, Marczewski & Butler, 2011; Schum & Pogash, 2011), the subjective and, in the case of the Smart et al. (2011) study, objective performance of first-time users was evaluated several times over the first month of use. Several questions focused on the perception of traditionally identified side effects of newly fit hearing instruments. These questions were:
- How comfortable are the hearing instruments in your ears?
- How comfortable are loud sounds?
- How is the sound of your own voice?
- What has your overall adjustment to the new hearing instruments been like?
These questions were asked on the day of the initial fitting, one day later, on day three, day seven, day 14 and finally day 30. The patients provided ratings on a scale ranging from 1 to 5, with five being excellent and one being very poor. The average results from 24 first-time users from Schum & Pogash (2011) is shown in Figure 4. The data from Smart et al. (2011) were quite similar. The ratings on these dimensions were high right from day one and stayed high throughout the course of the first month. The traditional viewpoint on the adjustment to amplification would have predicted that these ratings would have been low during the first few days or weeks of the fittings. These patients were fit with Oticon Agil Pro miniRITEs and many of the fittings were open. The combination of the advanced signal processing, the miniRITE design and open coupling allowed for acceptance of the fittings right from day one.
Figure 4. Ratings of side effects by first-time users from Schum & Pogash (2011).
These results led us to believe that patients no longer have to "put up" with side effects of newly fit hearing instruments, as long as the physical design and signal processing are of the highest level. As indicated earlier, the Oticon Intiga family of products is built upon a miniaturized version of the RISE 2 platform. At the Oticon Intiga 10 level, the product includes our well-known signal processing concepts such as Speech Guard, Spatial Sound, Voice Aligned Compression (VAC), DFC2 and intelligent fully automatic operation (Artificial Intelligence).
What does it take for a hearing device to be accepted easily by first-time users? It is important to remember that the typical first-time user is coming from a place where they can get by without amplification. It is not just a matter of whether or not the hearing instruments provide benefit. It is whether or not the benefit outweighs the downsides of being fit. The side effects of being fit with amplification must be kept low since the patient can choose to continue to get by without assistance.
During the first few days of hearing device experience, it is important that nothing catches the patient off guard in a negative way. Traditionally, many first-time users report being surprised about hearing the background sounds of daily life: the hum of the refrigerator, the "sound of the room", changes in the sound of their own voice, etc. All these sounds are second nature to the person with normal hearing or the experienced hearing device user, but have been absent in the experience of the typical first-time user for a number of years. The sudden re-immergence of these sounds may be attributed to faulty, "noisy" hearing device processing. All the new sounds that they hear should be helpful, not superfluous or annoying. In addition, the physical sensation of wearing devices needs to be acceptable. The device must feel light, non-occluding and comfortable.
We believe that Oticon Intiga is poised to be an excellent choice to provide a nothing-but-positive initial exposure to amplification. The following technologies play a big role in allowing for fast acceptance:
- Speech Guard
- Spatial Sound
- Open Fittings
- DFC2
- New Speaker & Wire Assembly
- Adaptation Management
- Fully Automatic Operation (Artificial Intelligence)
The physical design allows for an immediately comfortable fit, free of occlusion or other unnatural sensations. The speaker provides a stable fit in the ear canal. The likelihood of feedback is kept low. The stable, quiet sound picture provided by Speech Guard avoids the traditional, unnatural "sound of a hearing aid". Spatial Sound helps maintain a natural sense of where all of the sounds are coming from in the environment. The improved Adaptation Manager (see Appendix D for details) walks the balance of providing access to important speech information from day 1 without overwhelming the patient with levels of sound that catch them off guard. Once in place on the ear, the product requires little or no physical interaction by the patient. The low level of side effects combined with instant access to long-lost speech information allows the patient to quickly move from a tentative, suspicious or otherwise unsure mindset to one where the focus is on new communication access.
Improving Speech Understanding
Although the patient's initial agenda may be focused on appearance and initial sound experiences, eventually the benefit offered by the devices becomes the key to success. The traditional viewpoint is that it takes several weeks if not months for the full benefit of newly fit devices to become realized (e.g. Arlinger et al., 1996). Although it is true that it may take some time for the brain to make full use of the newly available high-frequency speech cues, that does not mean that newly fit devices do not provide benefit right from the start. For a patient with a mild-to-moderate sloping hearing loss, a new fitting should be providing greater access to speech information in frequency regions that carry a large amount of phonemic information (Kryter, 1962). Several studies in the past have shown that the immediate restoration of audibility improves speech information (e.g., Gatehouse, 1992). For example, Kreisman, Mazevski, Schum & Sockalingam (2010) found that the fitting of amplification improved both objectively measured performance in noise and also subjectively measured benefit across environments for first-time users.
In the work by Smart et al. (2011) and Schum & Pogash (2011), communication performance was tracked both subjectively and objectively immediately after the fittings and at several points in time during the first month of use. Figure 5 provides ratings from 24 first-time users of Oticon Agil Pro on the dimensions of understanding speech one-on-one in quiet, understanding speech in noisy environments and overall performance with the devices from Schum & Pogash (2011). As can be seen, these ratings start high and remain high right from day 1. Similar subjective results were found by Smart et al. (2011). Importantly, Smart et al. (2011) objectively measured speech understanding performance in quiet and noise at the same time intervals. That data is presented in Figure 6. These scores were extremely stable throughout the course of the first month. Importantly, similar results have been recently confirmed for first-time users of Intiga 10 (Behrens, Schulte & Kreisman, 2011).
Figure 5. Ratings of communication performance by first-time users from Schum & Pogash (2011).
Figure 6. Speech reception thresholds (HINT) in quiet and 65 dB SPL noise from Smart et al. (2011).
These data suggest that first-time users of advanced technology products such as Oticon Intiga or Oticon Agil Pro should expect hearing instruments to be helpful immediately. From the moment they walk out of the office on the fitting day, the user is hearing new amounts of information that should make speech communication across a range of environments easier. Intiga 10 incorporates all of the advanced technology that has distinguished Oticon Agil Pro as providing improved speech understanding and reduced listening effort (Sockalingam & Holmberg, 2010a). The product is built upon a new miniaturization of the RISE 2 platform. In order to provide a reduced sized RITE that runs on a 10A battery, the platform has been reduced significantly in size and the energy efficiency has been improved by 20%, yet it is still our fully featured wireless digital engine.
The following features combine to provide excellent performance across a range of listening situations:
- Speech Guard
- Spatial Sound
- Voiced Aligned Compression
- Multiband Adaptive Directionality
- TriState Noise Reduction
The fitting parameters of VAC provide access to speech information that is well proportioned to the dynamic range of the patient (see Appendix A for more details). Speech Guard manages the dynamic changes to maintain a stable, clean treatment of the on-going speech signal yet protecting against sudden, dramatic changes in the sound environment (see Appendix A for more details). In complex situations, Spatial Sound protects the natural cues to location with Multiband Adaptive Directionality and TriState Noise Management helping to minimize the deleterious effects of background noise. The combined effects of these signal processing elements have led to documented improvements in patient performance with Oticon Agil Pro (Sockalingam & Holmberg, 2010a, 2010b), and those same benefits have now been documented in patients using Intiga 10 (Behrens, Schulte & Kreisman, 2011).
Importantly, we have taken the time to examine the details of the adaptation process. With the increasing use of fully automatic hearing instruments, we originally introduced the concept of Adaptation Management in the late 1990's (Schum, 2001) as a way of transitioning first-time users into the world of amplified sound. A recent review of use patterns (Schum & Pogash, 2011) indicated that many professionals have been finding that Step 1 may be too weak for first-time users. Based on this observation, we evaluated different options for increases to the amount of audibility provided in Step 1. Figure 7 provides an overview of the nature of the adjustments in the updated Step 1. The primary adjustment is to increase the amount of gain applied for conversational levels of speech in the mid and high frequencies. The result is greater access to the main information content of the speech signal. Compared to more traditional compression approaches, the stable processing provided by Speech Guard allows amplified speech to maintain a more natural sound quality (see Appendix D for more details).
Figure 7. Schematic overview of the changes in the settings of Step 1 in the Adaptation Manager.
The new settings of Step 1 were compared to the original Step 1 for a group of 11 first-time users. Speech understanding in noise was evaluated at the time of the fitting for moderate level (55 dB SPL) speech inputs. The results, shown in Figure 8, demonstrate an improvement of greater than .5 dB on the day of the fitting, again demonstrating that performance with amplification even in noise can be immediately affected by the application of high quality amplification.
Figure 8. Speech understanding in noise for the new Step 1 settings compared to the original settings.
Long Term Satisfaction
Hearing care professionals certainly recognize that first-time fittings are at risk throughout the course of the first month and beyond. Although we expect the typical patient to experience a minimal amount of side effects and immediately improved speech understanding, we also wanted to take care in the design process to guard against reliability and comfort issues that can emerge later in the fitting. Data indicate that, traditionally, a significant number of newly fit devices end up being returned or simply not being used (Kochkin, 2000). Lack of benefit and the presence of side effects are usually cited as main reasons, but reliability is also a concern.
The following features are designed to minimize the occurrences of practical difficulties after the fitting, throughout the life-cycle of the Oticon Intiga (see Appendices B & C for more details):
- New speaker shape
- New wire
- New speaker connection
- New battery drawer
- Nano-coating & moisture-abating design
The surfaces are held clean giving Oticon Intiga a fine designed look and the width has been minimized giving good space for glass side bars behind the ear. The new curved speaker unit seats naturally in the ear canal, reducing the natural tendency to slip back out of the ear canal. The new thinner and more pliable wire construction conforms to the external ear contour and further reduces the tendency for the speaker to work itself out of the ear canal. The speaker connects to the body of the device using a new configuration that is more secure. The battery door includes a fingernail grip for easier access. The electronic components are fully sealed and construction details of the shell are designed to wick moisture out of the device using capillary traps. The sum total is to provide the user with a device that can be counted on over the years with a reduced likelihood of irritating practical problems that can demotivate the user, leading to non-use, device return and negative word-of-mouth.
Candidacy
Oticon Intiga represents the convergence of well-proven signal processing and a new physical design to improve acceptance by first-time users. Although the focus of this paper so far has been on what it will take to attract and satisfy first-time users, certainly Oticon Intiga is perfectly appropriate for existing users who are ready to upgrade their hearing device technology. Patients who were fit with either traditional products or design-based products three to five years ago are also excellent candidates. Again, the signal processing basis of Oticon Intiga has been shown in a series of studies to provide improved speech understanding with reduced listening effort. The fitting range (Figure 9) indicates that this is an appropriate product for hearing losses down to 75-80 dB HL. Although most first-time users will likely be fit with Domes, Micro Molds will be needed for some patients, both new and existing.
Figure 9. The fitting ranges of Intiga 10 and Intega 8 & 6.
Further, as indicated previously, Oticon Intiga is configured into the Essential, Advanced and Premium categories since some patients have true budget restrictions. Figure 10 on the following page provides the feature assignment to the three different levels of Oticon Intiga. The main differentiating features that set Intiga 10 apart are Speech Guard, greater bandwidth and the advance binaural features of binaural compression control and Spatial Noise Management. The main differentiating features between Intiga 8 and 6 are Binaural Synchronization and the sophisti-cation level of the automatic signal processing. All three products are prepared for connectivity, but only Intiga 10 offers Power Bass and Music Widening.
Figure 10. The feature table for Intiga 10, 8, and 6.
Connectivity
Oticon Intiga, based on the fully functional miniaturized RISE 2 platform, provides the full range of wireless features. First-time users will vary on their need and interest in connectivity options. The appropriateness of a discussion about connectivity may well be related to the behavior pattern that patients present when they enter the process (Schum, Weile & Behrens, 2011). For example, it may not be a good idea to discuss connectivity options right from the start with a patient who is hesitant about entering the hearing device process due to age-related stigma concerns. The need for additional, visible hardware may increase the patient's concerns about what other people may think. In contrast, a patient who is more comfortable with the idea of getting amplification may find the additional functionality a nice added bonus. As always, the discussion of connectivity should be tied to specific communication needs nominated by the patient.
Intiga 10 offers the enhanced Streamer functions of Power Bass and Music Widening. In order to preserve battery drain, only one of these two features can be activated for the patient at a given time. Given the typical loss of the first-time user, we assume the choice should more often be Power Bass, since many fittings will be open.
The Streamer also doubles as a remote control in the event that the need for user intervention develops over time. If the hearing care professional or the patient considers device control essential right from the start, two options exist: use the miniRITE products from the Agil, Acto or Ino product lines or dispense a Streamer with the Oticon Intigas. Sometimes the patient who assumes the need for device control (for example, existing users who have always had a volume control or switch on their devices) actually discovers that this is not needed due to effective fully automatic operation.
For such a patient, the physical styling of Oticon Intiga, including a more stable, comfortable physical fit, may be well appreciated with the Streamer only used occasionally as needed.
Final Thoughts
The goal of everyone involved is to improve communication as quickly and as effectively as possible for the person with untreated hearing loss. The hearing care professional is driven by the desire to get new devices on patients in a quick and efficient manner, but also in a way that insures long term satisfaction. The patient may recognize the presence of some level of hearing difficulties, but may not have the motivation to take action right now. Family members may have a different interpretation of how difficult communication currently is. Despite these different viewpoints, clearly an important part of the solution is the right hearing technology.
To ensure both immediate and longer term benefit, the signal processing needs to be excellent — providing access to the best speech information, effectively controlling competing noise and maintaining natural sound quality. In addition, due to the known hesitancy of many first-time users to accept hearing technology into their lives, the appearance of the device must be right. Patients simply will not have the opportunity to experience excellent signal processing if they are unwilling to even try to find out what amplification can do for them. Further, the initial listening experiences must be positive in order to maintain momentum. The first days of device use must provide a positive experience, acceptable, natural sound quality with a low downside.
Oticon Intiga provides a range of specific features in order to meet all three components: discreetness, acceptance and performance. The heart of the device provides the culmination of Oticon's very best approaches to signal processing, including Speech Guard, Spatial Sound and Artificial Intelligence. The physical and acoustic design of the product is such to make it as easy as possible for the first-time user to accept Oticon Intiga as the path to better communication performance.
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APPENDIX A
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APPENDIX A
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