The development of an mHealth educational intervention for first-time hearing aid users: combining theoretical and ecologically valid approaches

Abstract Objective: This paper describes the development of a novel mobile health (mHealth) educational intervention, called m2Hear, designed for first-time hearing aid users based on previously developed educational multimedia videos, or reusable learning objects (RLOs), branded C2Hear. Design: The development of m2Hear used theoretical and ecologically valid approaches. The COM-B model and associated Theoretical Domains Framework were employed to identify specific components (or “active ingredients”) of the original RLOs that facilitate hearing aid use. An mHealth platform was then developed following an iterative, user-centred and participatory design approach. Study sample: Fifteen existing hearing aid users completed synchronous, real-time Think Aloud interviews. A sub-group of these participants (n = 5), along with patient and public involvement panel members (n = 4), subsequently reviewed the usability of the mHealth platform. Results: While factors associated with Capability featured strongly across all RLOs, topics relating to Opportunity and Motivation were also incorporated. The RLOs were broken-down into 42 shorter mobile-enhanced RLOs (or mRLOs). Each mRLO was labelled with a specific user-centred question generated from the Think Aloud interviews. The final mHealth platform was developed following four separate usability iterations. Conclusions: Overall, m2Hear provides greater opportunities for individualised learning and encourages greater interaction to facilitate self-management in first-time hearing aid users.


Introduction
Individuals living with chronic conditions, such as hearing loss, are primarily responsible for managing their own health. Patient education is one of the core tenets of hearing loss self-management (Barker et al. 2016b), supporting the individual to use, handle, maintain and care for their hearing aids on an ongoing basis (Bennett et al. 2018). Information to support hearing aid management is typically delivered verbally by an audiologist. However, hearing aid users often forget or misunderstand important information given to them in this way (Reese and Smith 2006;Ferguson et al. 2015). Audiologists can also experience difficulties disseminating the large amounts of information that patients require during time-limited appointments (Bennett et al. 2018). These factors likely contribute to the finding that, despite improving quality of life and listening abilities, hearing aids are often used sub-optimally or not at all .
High-quality information, which supplements that given verbally by an audiologist, can resolve some of the issues surrounding suboptimal and non-use of hearing aids. In the United Kingdom, for instance, the provision of accessible patient information is strongly advocated in national quality standards and practice guidance for adult aural rehabilitation (British Society of Audiology 2016; National Institute for Health and Care Excellence 2018). Supplementary information typically takes the form of written materials, such as hearing aid user guides and/or manuals. Research in this area has consequently investigated whether these materials are set at an appropriate level for the intended target audience to understand (i.e. health literacy). In general, the majority of hearing aid user guides have been deemed unsuitable for the typical first-time hearing aid user age group, which may also help to explain why hearing aids are used sub-optimally (Caposecco, Hickson, and Meyer 2014). Improving the content, layout and readability of written materials, such as through the inclusion of pictures or graphics, increasing the font size, as well as reducing reading level, can improve hearing aid outcomes (Caposecco et al. 2016;McMullan, Kelly-Campbell, and Wise 2018).
In addition to issues surrounding health literacy, a further complication is that written information is not always given to patients as standard (Kochkin et al. 2010). Remotely delivered educational interventions provide an accessible alternative to written materials. Such interventions include videos (Kramer et al. 2005) and Internet-based programmes (Thor en et al. 2014), which have been shown to result in positive outcomes relative to standard care. Similarly, we have developed an educational intervention based on the concept of reusable learning objects (RLOs) (Ferguson et al. 2016a(Ferguson et al. , 2018. RLOs are bite-sized chunks of multimedia learning underpinned by pedagogical design principles. Specifically, an appropriate multimedia environment is created whereby the learner focuses on specific learning goals. The learner is further encouraged to take an active role within the RLO, through a combination of highly visual components (e.g. animations, video clips, patient testimonials), activities and selfassessments that are aligned with these goals.
To improve accessibility, we employed a user-centred and participatory design approach to develop a series of RLOs covering practical (e.g. How to insert hearing aids) and psychosocial (e.g. Communication tactics) aspects of the adult aural rehabilitation process (Ferguson et al. 2018). The effectiveness of the RLO intervention was assessed in a registered randomised controlled trial (RCT) (https://www.isrctn.com, ISRCTN11486888) of 203 first-time hearing aid users (Ferguson et al. 2016a). In comparison to a standard care control group, participants using the RLOs demonstrated significantly better practical hearing aid handling skills, better practical and psychosocial knowledge, and greater hearing aid use in suboptimal users. In a further clinically registered RCT (https://clinicaltrials.gov, NCT03912779), the RLOs were also shown to significantly improve self-efficacy for hearing aids (Gomez and Ferguson 2020). On completion of the first trial, the RLOs were further revised based on participant feedback and subsequently branded C2Hear. These RLOs are now freely available online via YouTube (https://www.youtube. com/c2hearonline), as well as a dedicated website (https://c2hearonline.com). However, the RLOs were originally developed for a DVD-mode of delivery. At the time of development (2011/12), Internet use in the typical first-time hearing aid user age group (70-74 years) was only 17% (Henshaw et al. 2012), suggesting that a DVD format would be most accessible to the target population. Consequently, opportunities for individualisation and interactivity were limited. Although participants in the original RCT could select the specific RLOs that they wanted to view, the average length of the videos was approximately eight-minutes. Some participants commented at the end of the trial that the RLOs were too long and hindered locating desired information with ease (Ferguson et al. 2016a). In addition, multiple-choice quizzes were included at the end of each RLO, which enabled participants to self-assess their mastery of the content and reinforce the intended learning goals. However, there were no opportunities to actively engage with the RLO content during learning to facilitate deeper understanding (Windle et al. 2011).
Providing healthcare via mobile technologies (e.g. smartphones, tablets, wearables), known as mobile health (or mHealth), is expanding rapidly as an accessible method of service delivery. In other chronic healthcare domains, such as diabetes, cardiovascular disease and asthma, mHealth interventions have been shown to increase individualisation and interactivity, improving self-management (Wang et al. 2014;Kim and Lee 2017). In addition, increasing individualisation and interactivity has been shown to enhance learning through active engagement with educational materials (Zhang et al. 2006;Evans and Gibbons 2007;Windle et al. 2011). The increasing digital literacy of older adults in the typical first-time hearing aid user age group suggests that mHealth interventions are likely an accessible and engaging method of providing educational support in this clinical population. In the United Kingdom (UK), for example, smartphone ownership in people over the age of 55 years has increased exponentially, from 40% in 2013 to 80% in 2019 (Deloitte LLP 2019). The proportion of 55-to 64-year olds accessing the Internet remotely via smartphones has also steadily increased, from 29% in 2012 to 64% in 2017 (Office for National Statistics 2017).
In this paper, we describe the development process of an mHealth educational intervention for first-time hearing aid users based on our original RLO-based educational intervention. In accordance with the UK Medical Research Council's (MRC) guidelines (Medical Research Council 2006), the development of the intervention was underpinned by appropriate theory. The original RLOs were developed using a participatory design approach and were underpinned by pedagogical design principles (Ferguson et al. 2018). However, since their development, there have been advances in the science of behaviour change theory, which presents a novel opportunity to retrospectively assess the theoretical basis of the RLOs. Specifically, we used the COM-B model (Michie, van Stralen, and West 2011), a contemporary, supra-theory of behaviour change that can enable intervention developers to better understand and describe patient behaviour (Coulson et al. 2016). The utility of this model is also being increasingly recognised and applied in range of audiological contexts (Barker, Atkins, and de Lusignan 2016a;Maidment, Ali, and Ferguson 2019). The model stipulates that for individuals to engage in a target Behaviour (B), they must have Capability (C), Opportunity (O), and Motivation (M). The COM-B model can also be incorporated into a larger system that includes the Theoretical Domains Framework (TDF). The TDF consists of 14 different constructs (Supplemental Materials 1) that can inform the identification of essential components, or "active ingredients", which can be incorporated in an intervention to bring about desired behaviour change.
The main objective of this paper is to describe how we developed an mHealth educational intervention (m2Hear) for firsttime hearing aid users using both theoretical and ecologically valid approaches. Specifically, this study aimed to: i. identify the "active ingredients" of the original C2Hear RLOs that facilitate the intended target behaviour (i.e. hearing aid use), theoretically grounded using the COM-B model and TDF; and ii. develop an mHealth platform that meets the needs of the end-user following an iterative, user-centred and participatory design approach for delivering individualised learning and increased interactivity.

Theoretical approach
Identification of the C2Hear RLO "active ingredients" The extent to which each of the 14 factors from the TDF were included within each C2Hear RLO was first identified by four independent researchers. One researcher (DWM) assessed all RLOs, with the remaining co-authors each evaluating a randomly assigned subset of six RLOs. A purpose-designed coding sheet was used to record the start and finish times within each RLO corresponding to the appropriate TDF factor. An example of a completed coding sheet for one RLO (How to insert your hearing aids) is provided in Supplemental Materials 2.
To ensure coding consistency, two RLOs (How to insert your hearing aids; What to expect when wearing hearing aids) were initially assessed independently by all four authors. This was then followed by a calibration meeting, whereby any discrepancies between assigned timings were discussed. An agreement was subsequently made among authors regarding which timings should be applied for each TDF factor. Following this meeting, the TDF factors for the remaining RLOs were mapped independently. Authors agreed that where a minimum of two researchers provided sufficiently similar timings (<5 seconds difference), no further action would be required. A final decision on further discrepancies was decided upon by MAF due to her audiological expertise.
The final agreed timings were used to calculate the percentage of time each the 14 factors from the TDF were included within each C2Hear RLO. For example, the total duration of the How to insert your hearing aids RLO was four minutes, with consensus among authors resulting in one minute and 51 seconds (46.25%) being coded as knowledge; one minute and 34 seconds (39.17%) as physical skills; 12 seconds (5%) as memory, attention and decision processes; 48 seconds (20%) as behaviour regulation; 26 seconds (10.83%) as social influences; 27 seconds (11.25%) as environmental context; one-minute and 18 seconds (32.5%) as reinforcement; and 13 seconds (5.42%) as optimism.

Ecologically valid approach
Generating the mobile-enhanced RLOs (mRLOs) The C2Hear RLOs were segmented into shorter mRLOs for delivery via mobile technologies, which was undertaken by two independent researchers. One researcher (DWM) segmented all the RLOs, with the remaining authors each segmenting a different, randomly assigned subset of four RLOs. The aim of this process was to break-down the C2Hear RLOs into mRLOs that were not only shorter in duration (approximately one-minute) but were also meaningful chunks of information that included a specific learning goal. Researchers recorded the start and finish times within each RLO that corresponded to an mRLO segment in accordance with these pre-specified criteria. On completion, all authors met to develop a consensus regarding which segment timings should be applied for each mRLO. Any differences between timings were discussed, and an agreement amongst all authors was made regarding which timings should be applied.

Labelling the mRLOs
We considered it important for the end user's voice to be embedded within the final mHealth intervention to improve learning potential. Consequently, a convenience sampling strategy was used (Patton 1990), whereby 15 existing hearing aid users were recruited from the National Institute for Health Research (NIHR) Nottingham Biomedical Research Centre (BRC) participant database. Demographic information of the sample is provided in Table 1.
Participants were invited to attend the NIHR Nottingham BRC, where written informed consent was obtained. A synchronous, real-time Think Aloud interview was then completed. The Think Aloud technique is an established observational method (Fonteyn, Kuipers, and Grobe 1993) that has been widely used in health research to evaluate digital interventions (Todhunter 2015). In this study, individual participants viewed the mRLOs and were required to reflect upon, describe and summarise the content in their own words. At the start of the session, a trained researcher (DWM) initially demonstrated what was expected, using the C2Hear Introduction video (https://youtu.be/ gZL8DUUKSKg) as an example. Participants were then provided an opportunity to ask any further questions before the Think Aloud interview began. All interviews were conducted face-toface, in a quiet room and lasted approximately one-hour in duration. Each interview was audio-recorded and transcribed verbatim.
The Think Aloud interview data were analysed by DWM using Braun and Clarke's (2006) established thematic analysis procedure, which comprises specific analytical phases: data familiarisation, generating initial codes, searching for themes, reviewing themes, and defining and naming themes. The analysis was inductive, as no pre-existing coding frame (or theoretical framework) was employed, and themes were defined as something important about the data that represented repeated patterns of response or meaning that were prevalent (i.e. reported by several participants) across the entire data set (Braun and Clarke 2006). A second researcher (MAF) reviewed the codes generated from all transcripts. Labels (i.e. themes) were derived for each mRLO, which were defined and redefined through re-analysis of the data and discussions among DWM and MAF. The final labels were affirmed by a project-specific patient and public involvement (PPI) panel, consisting of four individuals with lived experience of hearing loss.
Developing the mHealth delivery platform On completion of the Think Aloud evaluation, the mHealth intervention was developed by the Health and e-Learning Media (HELM) team at the University of Nottingham. The platform aimed to incorporate greater opportunities for individualisation and interactivity. Employing a user-centred and participatory design approach, a sub-group of participants were invited from the Think Aloud study (n ¼ 5), along with PPI panel members (n ¼ 4), who reviewed the usability of the mHealth platform. This process was iterative, whereby individual participants interacted with prototype-versions of the intervention in the presence of one researcher (DWM) at the NIHR Nottingham BRC, as well as remotely from home for up to one-week. During each iteration session, user perceptions and potential problems with the prototype versions of the platform were identified and collated. Feedback was then sent to the HELM team so that revisions could be made to the platform before the next iteration commenced. In total, four separate iterations were undertaken between November 2017 and February 2018, each taking approximately one-month to complete. This model of usability testing was an adaptation of the well-established methodology devised by the HELM team (Wharrad and Windle 2010) and was successfully used in the development of the original C2Hear RLOs (Ferguson et al. 2016a).
All participants were paid a nominal inconvenience allowance and travel expenses for taking part in the research. The study

Theoretical approach
Identification of the C2Hear RLO 'active ingredients' The percentage of time each TDF factor was included within each C2Hear RLO is summarised in Figure 1. On average, all RLOs included a high proportion of time relating to domains associated with the Capability component of the COM-B model (M ¼ 35.1%; SD ¼ 13.7). The proportion of time associated with Opportunity (M ¼ 19.8%; SD ¼ 0 13.7) and Motivation (M ¼ 5.8%; SD ¼ 4.6) was lower. Arguably, these results were to be expected given that the original C2Hear RLOs all aimed to improve knowledge of hearing aids and communication. This pattern of findings was also reflected in Figure 2, which shows the proportion of time each TDF factor was included within each individual RLO. The Hearing aid care RLO included TDF factors associated exclusively with Capability, with the highest proportion of time identified for Behavioural regulation (94.9%). The remaining RLOs included TDF factors related to Capability, as well as Opportunity and Motivation. A higher proportion of time relating to TDF factors associated with Opportunity, in comparison to Motivation, was found for the following RLOs: Using the phone and other devices, Communication tactics, Troubleshooting tips and Hearing aid retubing. The following RLOs included a high proportion of time relating to TDF factors associated with Motivation in comparison to Opportunity: Getting to know your hearing aids, How to insert your hearing aids, What to expect when wearing hearing aids, and Adapting to wearing hearing aids. Therefore, the C2Hear RLOs consisted of different "active ingredients", each associated with the different components of the COM-B model in order to facilitate the desired target behaviour (i.e. hearing aid use).

Ecologically valid approach
Generating and labelling the mRLOs In total, the C2Hear RLOs were segmented into 42 mRLOs, with a mean average duration of one-minute (range¼ 20 seconds, to 1 minute and 56 seconds). Labels for each mRLO derived from the Think Aloud interviews took the format of a question in the first-person singular. In addition, from the theoretical phase of the development process, each mRLO could also be classified according to the COM-B model and TDF. In Table 2, an example is provided for the How to insert your hearing aids RLO, which was segmented into three mRLOs, each labelled in accordance with the Think Aloud data and mapped onto the TDF and COM-B model. Data for all remaining mRLOs are provided in Supplemental Materials 3.
During the Think Aloud interviews, participants consistently reported that the mRLOs could be clustered according to their likely need and use along the patient journey post-hearing aid fitting (i.e. categorised according to relevant information required before hearing aid fitting, immediately after fitting, and up to six-weeks post-fitting). As a result, the following five highlevel categories were also generated from the Think Aloud data: (i) Using your hearing aids (which included mRLOs derived from the Getting to know your hearing aids and How to insert your hearing aids C2Hear RLOs); (ii) Getting used to your hearing aids (What to expect when wearing hearing aids; Adapting to wearing hearing aids); (iii) Looking after your hearing aids (Hearing aid care; Hearing aid retubing; Troubleshooting tips); (iv) Communication with others (Communication tactics); and (v) Using phones and other devices.
Developing the mHealth delivery platform The collated feedback generated by users during each of the four development iterations is summarised in Supplemental Materials 4. Technical issues (e.g. unresponsive taps/swipes when making an mRLO selection) and problems associated with usability (e.g. requirement of a back button to improve navigation) were identified and addressed. The final m2Hear intervention comprises the following individualised and interactive components, which can also be viewed online via https://www.nottingham.ac.uk/ helm/dev-test/m2hear/: i. Earmould coupling. On the initial landing page, there is an option to select either open fit or custom earmould hearing aids. ii. Five high-level categories. The mRLOs are subdivided into five high-level categories corresponding to the patient journey pre-and post-hearing aid fitting, which were added in accordance with participants comments during the Think Aloud interviews. iii. Series of 42 mRLOs. Each mRLO has a specific user-centred question, derived from the Think Aloud interviews (see Supplemental Materials 3). In addition, for increased individualisation, a 'Viewed videos' section is included and located at the bottom of each webpage so that the user can track when and how often an mRLO has been watched. This additional functionality was viewed favourably during    Opportunity iterative usability testing and was modified in accordance with feedback to improve usability (e.g. moved from the top of the screen to bottom, as the latter was considered less confusing and/or distracting). iv. Activities. Adapted optional activities were developed, based on the most frequently viewed RLOs from the original RCT evaluation, namely, Getting to know your hearing aids and How to insert your hearing aids (Ferguson et al. 2016a). We also opted to include activities on communication tactics that had been developed as part of another mRLO project aimed at frequent communication partners (Ferguson et al. 2019b). Each activity aimed to reinforce the learning goal of the associated mRLO. For example, the learning goal of the mRLO for How do I put my hearing aids in? is to understand how to correctly insert the earmould and hearing aid. The associated activity requires the user to drag five photographic images, each showing different stages of insertion, into the correct order. Feedback is provided based on the user's response. For a video demonstration of this activity, see Supplemental Materials 5. A description of all activities developed and included in m2Hear is summarised in Table 3. v. Quizzes. An optional multiple-choice quiz question was associated with the learning goal of 34 associated mRLOs. Each quiz question provides feedback and additional supporting information depending on how the user responds. For example, the How do I put my hearing aids in? quiz question requires users to select one of three photographic images showing the earmould and hearing aid inserted correctly, and appropriate feedback is provided depending on how the user answers. For a video demonstration, see Supplemental Materials 6.

Discussion
In the current paper, we have described the development of an mHealth educational intervention designed specifically for first-time hearing aid users. Using a combined theoretical and ecological approach, we aimed to update our original C2Hear RLO-based intervention (Ferguson et al. 2016a), which provides limited opportunities for individualisation and interactivity due to the DVD-based mode of delivery. Our rationale for redevelopment was grounded in existing evidence that mHealth interventions improve self-management of other chronic health conditions, primarily due to greater accessibility and opportunities for user engagement (Wang et al. 2014;Kim and Lee 2017). As a result, we have repurposed the C2Hear RLOs into a series of shorter mRLOs delivered via an mHealth platform, called m2Hear, to enhance learning potential through increased individualisation and interactivity.
A key strength of the m2Hear development process was its theoretical underpinning. According to UK MRC (2006) guidance, it is important to draw on existing theory to understand the processes that are necessary to facilitate optimal health behaviour change. The value of such an approach is that it has the potential to increase the likelihood that complex healthcare interventions will be effective. Although previously developed educational interventions for hearing aid users have been shown to provide a range of patient benefits (Kramer et al. 2005;Lundberg, Andersson, and Lunner 2011;Thor en et al. 2014), they did not report whether existing theory and/or design principles were employed during the development process. In comparison, the design of our original C2Hear RLOs were theoretically underpinned by pedagogical principles to ensure that an appropriate multimedia environment was created (Wharrad and Windle 2010). The current study extends this original design approach, employing the contemporary COM-B model and TDF to identify the "active ingredients" of the original C2Hear intervention that facilitate the target behaviour of hearing aid use.
An advantage of using the COM-B model and TDF, as opposed to other theories and models from health psychology, is that it is a framework that has been specifically designed to inform the development and evaluation of complex behaviour change interventions (Coulson et al. 2016). In the current study, through identification of specific intervention functions that facilitate the desired target behaviour (i.e. hearing aid use), we found that TDF factors associated with Capability (i.e. Knowledge, Physical skills, Behavioural regulation) featured strongly across all C2Hear RLOs. This was perhaps unsurprising, given that the original intervention aimed to improve knowledge of hearing aids and communication in first-time hearing aid users. In the original RCT that assessed the provision of the RLOs in first-time hearing aid users, knowledge was significantly improved, with large clinical effect sizes, which also led to a significant improvements in practical hearing aid handling skills, again with large clinical effect sizes (Ferguson et al. 2016a). The need to develop an educational intervention to facilitate these aspects of hearing loss self-management originated from existing findings that hearing aid users continue to experience difficulties after fitting, including problems associated with regular care and maintenance, as well as discomfort (McCormack and Fortnum 2013). This was subsequently confirmed in our Delphi review of hearing professional stakeholders (Ferguson et al. 2018).
Nevertheless, in addition to Capability, we also found that specific C2Hear RLOs incorporated topics relating to Opportunity (e.g. Social influences, Environmental context) and Motivation (e.g. Intentions, Reinforcement, Optimism, Beliefs about consequences). The importance of social and environmental factors in adult aural rehabilitation should not be underestimated, given that family and friends (or frequent communications partners) play a pivotal role in hearing loss selfmanagement (Kamil and Lin 2015;Barker, Leighton, and Ferguson 2017). Motivational factors, such as confidence (or selfefficacy) and readiness to use hearing aids, have also been shown to effect hearing aid outcomes, including use, benefit and satisfaction (West and Smith 2007;Dullard and Cienkowski 2014;Hickson et al. 2014;Kelly-Campbell and McMillan 2015;Ferguson, Woolley, and Munro 2016b). Furthermore, in a registered RCT, providing C2Hear at the hearing assessment was shown to improve knowledge of hearing aids and communication, as well as hearing aid self-efficacy when measured at hearing aid fitting (Gomez and Ferguson 2020). Whether this "early" provision would impact long-term hearing aid outcomes requires further investigation. By using the COM-B model as an underpinning framework, we can better understand how C2Hear, as well as m2Hear, likely facilitate hearing aid outcomes in firsttime users. A further strength of our mHealth developmental process was that key stakeholder input from adults with lived experience of hearing loss was incorporated throughout. Similarly, the original C2Hear RLOs were also developed using a user-centred and participatory design approach; hearing aid users and hearing healthcare professionals were consulted throughout the development processes to ensure that the needs and experiences of the end user, as well as clinical validity, were captured (Ferguson et al. 2018). Adopting a similar approach in the development of m2Hear, after identifying the 42 shorter mRLOs with a specific learning goal, we then involved existing hearing aid users. They participated in Think Aloud interviews, describing the content of the individual mRLOs in their own words. This led to the generation of labels for each mRLO and ensured that the user's voice was embedded within the final mHealth intervention. An advantage of involving stakeholders in intervention development is that it can lead to the generation of engaging resources that are aligned with the specific needs and personal preferences of the end-user (O'Keefe, O'Regan, and Cashman 2008). Thus, it was expected that this approach would subsequently improve usability and, ultimately, intervention effectiveness.
Following development, m2Hear was evaluated in a registered study (https://clinicaltrials.gov/, NCT03136718) to investigate the feasibility of the intervention in naïve first-time hearing aid users. Specifically, following approximately 10 weeks of independent use in their everyday lives, we investigated delivery, accessibility, usability, acceptability, and adherence of m2Hear using a mixed-methods approach in first-time hearing aid users. Semi-structured interviews provided an in-depth insight into participant's experiences, with participants reporting that m2Hear is a concise and comprehensive resource, enabling greater individualisation and independence to self-manage hearing loss, leading to empowerment to better manage hearing aids and communication (Ferguson 2019;Maidment et al. in press). Patient-reported outcome measures also showed a range of benefits of m2Hear when used in conjunction with hearing aids, including improved hearing-related quality of life, hearing aid self-efficacy, social participation, as well as knowledge of hearing aids and communication (Ferguson et al. 2019a;Ferguson et al. under review). In addition, usability was rated highly and most participants agreed that m2Hear was pitched at the right level. These latter findings likely reflect the high levels of user-involvement in the development.
The next stage in the evaluation process would be to assess the effectiveness of m2Hear versus standard aural rehabilitation practices in an RCT. A future RCT might consider evaluating m2Hear as a single intervention and/or as part of a comprehensive package that also incorporates additional elements that have also been identified to support successful self-management, such as monitoring, psychosocial factors, cues to action and collaborative decision-making (Barker et al. 2016b;Convery et al. 2018Convery et al. , 2019.

Study limitation
Despite these strengths, we acknowledge that our development process may be limited in its generalisability. Namely, in the user-centred, participatory design approach employed in the current study, hearing aid users were recruited from the NIHR Nottingham BRC participant database. Most individuals in this database are current or former patients of the Adult Audiology Service at Nottingham University Hospitals NHS Trust. As a result, the findings derived from our ecologically valid methods might be limited in their application to other clinical settings. Nevertheless, despite this potential confound, m2Hear would likely be appropriate for patients based throughout the United Kingdom, as well as internationally.

Clinical implications
Form a UK perspective, the provision of high-quality information has been endorsed in national quality standards for adult aural rehabilitation (National Institute for Health and Care Excellence 2018). Subsequently, over 40 NHS and independent sector audiology services based in the UK have started implementing the C2Hear RLOs into their clinical practices. In addition, since its launch in November 2015, the C2Hear YouTube channel (https://www.youtube.com/c2hearonline) has received over 260,000 unique views, 70% of which originate from other countries, including the United States of America (USA) (31%), India (9%) and Canada (3%). While some of the RLO content might be more appropriate for UK-based patients, the RLOs can be easily adapted for international audiences. For example, the C2Hear RLOs have been modified for patients living in the USA (i.e. voice over and subtitles in American English), and have subsequently been incorporated into a 'best-practices' hearing intervention evaluated as part of the Aging and Cognitive Health Evaluation in Elders (ACHIEVE) study (Deal et al. 2018).

Conclusions
Taken together, this research has resulted in the development of theoretically driven, user-centred mHealth intervention that can be delivered through mobile technologies to support self-management of hearing loss in first-time hearing aid users. Called m2Hear, this novel mHealth educational intervention provides opportunities for individualised learning and encourages greater interaction. Given that the use of mobile technologies in hearing healthcare is expected to continue to rise, there is a clear opportunity for audiologists worldwide to harness mHealth to improve access to hearing healthcare. In the present paper, we have argued that a key area where mHealth technologies are advantageous is through the delivery of remotely-delivered educational information that can be individualised and is more interactive compared to previously developed materials (Kramer et al. 2005;Thor en et al. 2014;Ferguson et al. 2016a;Gomez and Ferguson 2020). On this basis, mHealth educational interventions have the potential to facilitate a more patient-centred approach, empowering patients to be more active participants in the management of their hearing health. The extent to which mHealth educational interventions can reduce the time needed for audiologists to verbally disseminate large volumes of information to patients during clinical appointments also warrants investigation. Therefore, further research is necessary to confirm whether the additional functionality afforded by m2Hear leads to improved hearing outcomes in comparison to standard aural rehabilitation practices.