Chronic kidney disease (CKD) affects approximately 10% of the global population [1] and is associated with significant morbidity, disease burden, and excess mortality [2]. Most individuals living with CKD have early-stage disease and are usually managed in primary care by their general practitioner or family physician [3]. As a result, people with early-stage CKD do not have access to the same specialist support, education, and training as those looked after by specialist kidney teams and are not well informed about their condition and its implications [4,5]. Improving people’s knowledge of CKD and its complications is paramount for optimal management to prevent disease progression and associated health problems [6].

Over the last decade, self-management interventions for CKD have gained popularity [7], in part due to the increasing recognition of the importance of incorporating patients and their families in managing long-term health conditions to improve outcomes [8]. One approach to delivering self-management education and support is the use of digital technology and tools. Digital health interventions (DHIs) have the potential to address self-management educational and support needs as they are largely accessible by most of the population, can be highly effective, and are delivered at low cost [9]. Despite DHIs becoming more readily available for people with CKD, few are theory based, and the development strategies and processes are unclear [10]. Adoption of appropriate methods is essential when developing DHIs to ensure effective implementation [11]. In addition, the codevelopment of DHIs with patient partners is crucial for their success, particularly in combination with usability testing [12,13], to ensure that relevant needs, priorities, and issues are addressed.

To support self-management in people with nondialysis CKD, we codeveloped “My Kidneys & Me” (MK&M), an evidence- and theory-based DHI that provides tailored, interactive information and support to improve CKD awareness and understanding, health knowledge, health-promoting behaviors, and confidence [14,15]. MK&M was codeveloped with kidney health care professionals and researchers and specialists in the development of complex interventions and digital health, in partnership with individuals living with CKD and their relatives. Intervention Mapping was used as a framework to guide the development processes of MK&M, in combination with several theory-informed intervention methods and practical strategies to facilitate behavior change. The MyDESMOND platform was used to host the MK&M DHI; MyDESMOND is an award-winning DHI on a quality-assured platform, which has been successfully developed and implemented [16] and is known to be well-accepted and effective [17]. The MK&M DHI has been evaluated in a multicenter randomized controlled trial (RCT), Self-Management Intervention through Lifestyle Education for Kidney Health (SMILE-K), which demonstrated positive effects, particularly for those with low levels of activation (knowledge, skills, and confidence in managing their own health) and in those who used the program more [10].

Similar theory-informed DHIs for CKD self-management have been co-designed, using frameworks to guide development, in the United Kingdom [18,19], Canada [20], and the United States [21]. Similarities and differences between MK&M and these DHIs have been described elsewhere [14]. Kidney Beam, a DHI addressing physical and emotional well-being [18,19], has demonstrated improvements in mental health–related quality of life in a multicenter RCT [22]. In a preliminary evaluation, My Kidneys My Health [20] has been shown to provide accessible content and tools that may improve self-efficacy and support in CKD self-management [23], but a larger trial is warranted. Qualitative exploration of a mobile app to support CKD self-management [21] suggested that individuals with CKD and their health care providers believe that the app can enhance CKD self-management by facilitating patient–health care provider communication and enabling self-care activities; however, its effectiveness on patient outcomes has not yet been evaluated.

Alongside demonstrating the efficacy of DHIs, the use of and engagement with DHIs are considered important when evaluating their effectiveness [24,25] and may be regarded as a prerequisite for the intervention to achieve positive outcomes [26]. Engagement, defined as users’ regular interaction with a part or all of the DHI [27], has been typically conceptualized as “use” [24], with a focus on temporal patterns (eg, frequency and duration) and depth (eg, use of specific intervention content) [28,29]. Although the primary aim of the SMILE-K trial was to determine the efficacy of MK&M on patient activation and self-management knowledge and behaviors [10,15], a secondary aim was to gain insight into participants’ use and experiences of MK&M. In this paper, we aimed to report the use metrics and patient experiences of using MK&M during a 20-week evaluation as part of the SMILE-K RCT.

This analysis comprises data collected as part of the SMILE-K trial (ISRCTN18314195). The SMILE-K study protocol [15], pilot study [30], and primary findings [10] are published elsewhere. As this paper reports on the use metrics and user experience of using MK&M, the data presented are from the intervention group only.

The SMILE-K trial was a single-blinded 20-week prospective, mixed methods, multicenter randomized controlled, parallel-group trial recruiting patients from 26 hospital sites across England, between May 2021 and December 2022. All study processes were conducted remotely due to the COVID-19 pandemic and for pragmatic evaluation. Full details of the study processes are published elsewhere [15].

This study was fully approved by the Research Ethics Committee-Leicester South on November 19, 2020 (17/EM/0357). All participants gave web-based informed consent for the trial; interview participants provided additional consent before the commencement of the interviews. The study was conducted per the Declaration of Helsinki. The trial was sponsored by the University of Leicester.

The study was prospectively registered on ISRCTN Registry (ISRCTN18314195) on December 18, 2020. Data were anonymized or deidentified.

Outcome measures were collected using Jisc Online Surveys or via the MK&M platform at baseline, 10 weeks, and 20 weeks. The primary outcome of the SMILE-K trial was the Patient Activation Measure (PAM-13), which assesses an individual’s knowledge, skills, and confidence in managing their health care [31] and ability to effectively self-manage [32], and it has been validated in CKD [33]. The PAM-13 is scored from 0 to 100 and can be categorized into 1 of 4 levels: levels 1 and 2 indicate low activation, and levels 3 and 4 indicate high activation.

Sociodemographic data, including age, sex, ethnicity, and social deprivation (postcode), were collected. Clinical data, including eGFR, etiology of renal disease, other health conditions, hemoglobin, and albumin, were extracted from medical records.

Access to and use data of MK&M were collected, alongside perceived usefulness (scored from 0 [not useful at all] to 10 [very useful]) of MK&M content and features. The frequency and length of time spent on MK&M sessions, health and symptom tracker use, and use of other MK&M features (eg, goal setting) were collected via the MK&M platform. Perceived usefulness of MK&M content and features were collected via web-based surveys. Participants were asked to rate how useful they found the MK&M sessions and features out of 10, where 0 was “not useful at all” and 10 was “very useful.”

In total, 420 participants were recruited into the SMILE-K trial; of which, 280 (66.7%) participants were randomized into the intervention group and were subsequently provided access to the MK&M program (mean age 59.4, SD 13.6 years; n=161, 57.5% male; n=254, 90.7% White British; eGFR: mean 38.4, SD 17.1 mL/min/1.73 m²) and are included in the analyses. Intervention group participant characteristics are displayed in Table 1.

In total, 225 participants activated their MK&M account across the 20-week study period; of which, 223 (99.1%) activated their account within the first 10 weeks. Over the 20-week study period, only 15 (6.7%) participants accessed their MK&M account once. A total of 63 (28%) participants accessed their MK&M accounts between 2 and 5 times, 40 (17.7%) participants accessed 6 to 10 times, 37 (16.4%) participants accessed 11 to 20 times, and 70 (31.1%) participants accessed >21 times over the 20-week study period. The median number of log-ins per person over 20 weeks was 10.0 (IQR 4.0-28.0); for the first 10 weeks, the median number of log-ins was 5.0 (IQR 1.0-17.0). Over the 20-week study period, the median time per log-in was 12:35 (IQR 6:51-24:55) minutes; for the first 10 weeks, the median time per log-in was 12:07 (IQR 7:16-24:32) minutes.

Individuals with low levels of patient activation (PAM-13) logged into the MK&M program a median of 4.0 (IQR 1.0-11.0) times in 10 weeks and a median of 9.0 (IQR 3.3-19.5) times in 20 weeks. Individuals with high levels of patient activation logged into MK&M a median of 6.0 (IQR 2.0-20.0) times in 10 weeks and a median of 11.0 (IQR 4.5-29.0) times in 20 weeks. Those with low patient activation spent a median time on MK&M per log-in of 14:04 (IQR 7:37-29:50) minutes, while those with high patient activation spent a median of 11:29 (IQR 6:40-23:08) minutes on the program per log-in across 20 weeks. No significant differences were observed between the two groups for total number of log-ins (P=.78) and time spent on the program per log-in (P=.45).

Table 2 displays learning and action (“How to...”) sessions by total number of times accessed and total duration spent on each session. Overall, “The kidneys” session was accessed by most participants (154/225, 68.4%), followed by the “Kidney disease” (145/225, 64.4%) session. Among the 225 participants, the most viewed learning sessions were “Eating a healthy balanced diet” with 107 (47.6%) participants and a median of 15 (IQR 15-17) views and “Managing my symptoms” with 95 (42.2%) participants and a median of 15 (IQR 15-17) views. The most viewed action session was “How to move more and be active,” with 104 (46.2%) participants and a median of 13 (IQR 13-18) views. The least viewed sessions were “Looking after my well-being” (n=82, 36.4%; median 7, IQR 7-9 views) and “How to look after my well-being” (n=67, 29.8%; median 6, IQR 5-9 views).

Participants spent the longest time on the “Kidney disease” (median 10:57, IQR 06:23-16:37) and the “Kidney disease and general health” (median 10:52, IQR 05:40-16:37) learning sessions; “How to set my own goals” (median 07:50, IQR 03:20-18:16) and “How to move more and be active” (median 07:21, IQR 03:16-12:51) were the action sessions that the participants spent the longest on.

In total 40 (18%) participants used the goal-setting and decision-maker (action planner) tools. Of those, 18 (n=40, 45%) participants set more than one goal, with 28% (5/18) setting 5 or more goals. Physical activity (23/40, 57%) and weight loss goals (22/40, 55%) were the most commonly set goals by participants, with more than half of goal-setting users creating action plans for these goals. Goal setting was considered one of the most useful trackers (mean score 7.3, SD 3.0; median score 8.5, IQR 5-10).

Of the 225 participants, a quarter of participants (n=56, 24.9%) used the blood pressure tracker and 42 (18.7%) used the cholesterol tracker. A total of 26 (11.6%) participants used the smoking tracker, despite only 9 (4%) reporting smoking. The healthy eating and shape trackers were used by 53 (23.6%) and 49 (21.8%) participants, respectively.

A total of 96 (42.7%) participants tracked their daily step count; of which, 55% (n=53) provided self-reported data and 28% (n=27) imported data from their Fitbit, 11% (n=10) from Google, and 6% (n=6) from a Garmin device. The mean number of days the steps were tracked was 74.3 (SD 50.2; median 69, IQR 22-125), with the mean number of daily steps recorded of 5952.5 (SD 5952.5; median 6189, IQR 2321-8576). Among the 225 participants, 31 (13.8%) used the strength training tracker. The mean duration of sessions was 44.0 (SD 29.2; median 30, IQR 30-52) minutes, with the mean number of repetitions performed per session of 145 (SD 79; median 100, IQR 100-200). The median effort reported per session was 7 (IQR 6-8) out of 10.

The symptom tracker was used by 50 (22.2%) participants, with participants tracking symptoms for a mean of 29.3 (SD 58.7) times (median 11, IQR 3-26 times). Of those, sleep disturbances and tiredness were the symptoms tracked by most number of participants (n=36, 72% and n=35, 70%, respectively), with participants tracking the symptoms for a mean of 3.9 (SD 5.8; median 2, IQR 1-4) and 4.5 (SD 7.5; median 2, IQR 1-4) times, respectively. Bone or joint pain and muscle loss were the most frequently tracked symptoms, with participants tracking for a mean of 4.8 (SD 8.5; median 2, IQR 1-4) and 4.8 (SD 8.8; median 2, IQR 1-3) times, respectively. Table 3 displays symptom tracker use data.

Tables 2 and 3 display the ratings of perceived usefulness for MK&M sessions and features. All sessions scored a mean ≥7 (median ≥8) out of 10. “Kidney disease” was considered the most useful session, with participants rating it a mean of 8.7 (SD 1.9; median 10, IQR 8-10) out of 10, followed by “The kidneys” (mean 8.6, SD 2.0; median 9, IQR 8-10). “Eating a healthy balanced diet” was perceived to be the least useful learning session, with participants rating it a mean of 8.0 (SD 2.3; median 9, IQR 7-10). The action session perceived to be the most useful was “How to look after my well-being,” rated a mean of 7.7 (SD 2.6; median 8.5, IQR 7-10) out of 10. The session perceived to be the least useful was “How to set my own goals,” rated a mean of 7.3 (SD 2.7; median 8, IQR 5-10) out of 10.

The cholesterol, strength training, and physical activity trackers were perceived to be the most useful trackers, with mean ratings of 7.7 (SD 2.4; median 8, IQR 5-10), 7.5 (SD 2.6; median 8, IQR 5-10), and 7.3 (SD 2.8; median 8, IQR 5-10) out of 10, respectively. The smoking tracker was perceived to be the least useful tracker, with a mean rating of 6.7 (SD 2.9; median 7, IQR 4-10) out of 10.

In total, 6 PPI partners participated in a think-aloud interview (n=3, 50% male; mean age 68.3, SD 9 y). Of the 36 intervention group participants invited to be interviewed, 31 (86%) responded, and 27 (75%) individuals were interviewed (mean age 61.7, SD 9.2; range 38-76 years; n=16, 59% male; n=25, 93% White British; mean eGFR 34.1, SD 11.7 mL/min/1.73 m²). A total of 34 interviews were conducted, with 7 participants interviewed twice at 10 and 20 weeks. Interviews lasted an average of 60 (range 32-96) minutes. Participant characteristics are displayed in Table 4.

This mixed methods study explored the use, usability, and user experience of the MK&M program to identify the content and features accessed, used, and valued. The study findings provide a detailed account of how users engage with and experience MK&M and suggest that the program is well-received and used by participants. Interviewing participants about their experiences provides detailed context and explanation of the quantitative data, helping to further understand the use metrics data. The integration of qualitative and quantitative findings allows for a comprehensive evaluation of the use and usability of MK&M, highlighting areas requiring attention and considerations for revising and adapting the program to improve user experience.

The educational sessions were the most valued and engaged content, while the health and symptom trackers were the least used features. The MK&M sessions mostly accessed and used were about kidneys, kidney disease, and how CKD relates to general health. This is not surprising given the need and appetite for kidney education [39]. There is a concerning lack of knowledge about kidneys, with many people not aware of what their kidneys are for or even where they are [40]. For those affected by CKD and its associated effects, being able to understand what to do, make decisions, and take action is imperative for individuals to better self-manage [40]. Interview participants in this study felt that as MK&M was specifically for people with CKD, it made them feel personally involved and empowered to manage their condition. For people with long-term conditions, such as CKD, specifically designed DHIs can empower and motivate them by providing feelings of reassurance and the ability to self-manage their condition [41]. Findings from the main trial evaluating MK&M demonstrated that it was effective at improving people’s knowledge, skills, and confidence in managing their CKD, alongside improving self-management behaviors, particularly for those with low levels of preexisting patient activation [10]. Despite logging in slightly less than those with high patient activation, those with low levels of activation spent longer on MK&M per log-in, with the total time spent on MK&M across the study period comparable between the two groups. This is encouraging as, overall, there is little difference in the engagement with MK&M for low and high-activated patients. Individuals who perceive DHIs as beneficial for their health are more willing to adopt and engage with them [42]. Greater adoption and engagement levels are observed when DHIs are based on individuals’ needs and preferences and are perceived as valuable additions and tools that can enhance individuals’ overall health and well-being [43].

MK&M was well-received by participants, with many reporting that the user interface was easy to use, with clear and logical navigation and appropriate presentation of information. Design features, ease of use, perceived usefulness, and personalization are key factors influencing user experiences [44] and empowering individuals to engage with DHIs [45]. Being able to access and use MK&M at one’s own pace and leisure was identified as an important facilitator for engagement. Having control and autonomy over the type, time, and location of intervention access is considered advantageous over traditional face-to-face care [46]. Moreover, user experience, including usability, acceptability, and satisfaction, has been shown to play a crucial role in the successful implementation and long-term engagement with DHIs [47]. Maintaining interest in the intervention over time has been identified as one of the main challenges of DHIs [48]. Website log-ins, a commonly used indicator of engagement and intervention exposure, often decrease over time [49,50]. We did not observe a decrease in MK&M use over the study, with a similar number of log-ins and time spent on MK&M observed between 0 weeks and 10 weeks, and 10 weeks and 20 weeks. However, as the study period was only 20 weeks, no user metric data were obtained beyond this. Further work is needed to assess the long-term use of MK&M. In addition, evaluating the impact and attrition of MK&M after implementation in real-life settings is required, as evidence suggests that use and engagement with DHIs are greater in trial users compared to “real-life” users [51,52]. Work is planned to explore users’ perspectives of implementation requirements and sustainability of MK&M, alongside embedding MK&M into routine clinical practice.

User engagement with MK&M was much greater than other self-management DHIs, including those for diabetes [53-55], with MK&M participants spending approximately 2.5 hours on the program across the 20-week study period, with some accessing MK&M more frequently and for longer periods. Interview participants reported spending significant periods using MK&M; however, they also expressed a need to dedicate more time and priority to the program, as they felt they had more to gain from MK&M. The learning sessions were more widely accessed and used than the action (“How to...”) sessions, and while it is not explicitly clear why this was the case, participants did highlight not having enough time to engage with all the MK&M content in the study period. Other DHIs have found that there is greater exposure to content which appears earlier in the program [55]; consequently, most users are not exposed to the broader theory- and evidence-based content that goes beyond information giving [55] and is found to be most effective and important for behavior change [56]. Lack of exposure to enough of the intervention content because of poor user engagement can make intervention effectiveness difficult, which is a common issue relating to DHIs [57]. Consideration must be given when implementing DHIs, including MK&M, to ensure that there is adequate and equitable exposure to the different constructs of self-management (ie, medical, emotional, and role). Identification of methods to increase exposure and encourage engagement with the active components of DHIs is required [55]; this may involve health care professionals signposting users to the relevant information and support. Although MK&M provides users with the flexibility to access and use the content in a way that is most useful, use metrics suggest that individuals may work through MK&M in a more structured fashion and perhaps are not exposed to the behavior change theory–driven content. Further work is required to understand approaches to increase exposure to the important self-management and behavior change content that can improve patient outcomes.

Generally, MK&M users had positive experiences of using the program; however, there was ambivalence regarding content and features, which could be explained by personal preference rather than usability issues. Substantial ambivalence has been reported for DHIs, with a diversity of experiences identified that are considered unique to each individual [41]. One notable concept is that some users want to be part of a sharing community while others prefer privacy [41]; the MK&M chat forum had mixed opinions, but despite many perceiving it as not relevant for them, they could see how it might be valuable for someone else. In addition, there were variations in the use and perceived usefulness of the health, symptoms, and physical activity trackers and goal-setting features. Lower engagement with tracking tools has been observed for other self-led programs [58] and where users engage with other digital tracking tools outside of the program [59]. Greater use of DHIs and their trackers to support self-monitoring and management is associated with better outcomes [60-62]; thus, further work on understanding factors influencing the use of the trackers and goal-setting features in MK&M is warranted.

Participants had a desire for continued learning and perceived the relevance of MK&M to be greater with time and disease progression. The use of DHIs is dynamic, and there may be more active periods when users engage more intensively and periods of moderate use or nonuse [63]; however, these few active periods are considered a part of the engagement process and may not mean that participants are not engaged anymore [63]. It is argued that adherence goes beyond using the DHI and relates more to adhering to the intended use that corresponds to desired goals [64]. The ability to create a routine with a DHI and incorporate it into part of your daily life is an important component of behavioral engagement [63]. This is something that participants in our study recognized and were hoping to prioritize and dedicate more to using MK&M. It appears that engagement with MK&M may fluctuate over time and respond to changes in health and disease progression. Raising patient awareness of CKD and its associated complications is essential for optimal management [6]; thus, providing intervention at an early disease stage can enable individuals to become more familiar with and make better sense of the information. Providing insights into users’ health, feelings of empowerment over being in control of their health, and improving skills have been found to facilitate DHI engagement [65]. Understanding the most appropriate time to offer MK&M to people with CKD is needed, and it is currently being explored.

Participants in this study did not experience any difficulties in using MK&M, despite some issues with activating their MK&M accounts. It is important to note that this trial was remote and virtual in nature, and thus, to be able to participate, individuals needed a certain level of digital literacy. Although not the focus of this study, it is necessary to acknowledge that digital poverty exists, with disparities in access to and proficiency in using digital devices and technology. Individuals with poor digital literacy and without access to digital technologies, particularly those with lower socioeconomic status and living in rural areas, may face greater challenges in adopting and using DHIs [66]. Bridging this gap requires conscious efforts to improve digital literacy, provide support and training, and ensure equitable access to technology and internet connectivity [67]. Improving the equity of access for those who are potentially disadvantaged and stand to benefit from MK&M is crucial. Future work should explore how we can improve digital inclusion for disadvantaged and underserved groups.

Primary findings from the SMILE-K trial suggest that when used, MK&M leads to important improvements in patient activation and related CKD self-management behaviors, with greater improvements observed in those with low patient activation at baseline [10]. Findings suggest that there is a need and appetite for DHIs among those with CKD to better manage their health, and MK&M is an appropriate means to deliver kidney health education to improve patient activation and self-management. For this study, MK&M was not prescriptive and provided minimal health care professional contact; participants were provided access to MK&M and left to use the program as they wished. Although there are many factors that affect an individual’s ability to engage with DHIs [68], this work provides a comprehensive evaluation of how users engage with and experience MK&M. In addition, this work highlights key areas that require attention and consideration. The findings of this study will be used to revise and adapt MK&M to improve accessibility, support uptake and engagement, and improve user experience and interaction with the platform.

This study has several strengths and limitations. A key strength of this study was the integration of qualitative and quantitative results, which helped to provide a more comprehensive understanding of the use, usability, and user experiences of the MK&M program. The inclusion of qualitative methodology, including think-aloud, enabled us to explore user experiences of the program and provide context to the quantitative findings, giving us a richer depth of insights into how MK&M was perceived and used.

A limitation of the qualitative substudy was the potential bias of the participants recruited, which may limit the generalizability of the findings. Although the participants interviewed generally had positive feedback, it may be that those who had different opinions or negative experiences were not willing to participate. Although the intended sample size was selected using the maximum variation technique, there was self-selection bias as several participants who were invited to be interviewed did not take part. In addition, due to the virtual nature of the trial and the intervention, individuals with low levels of digital literacy were likely disadvantaged, and individuals without access to digital technology were ineligible. Thus, those involved in the main trial and the qualitative substudy had to have had some level of digital literacy to be able to enroll in the study, and thus it is not known how individuals experiencing digital poverty may have used or engaged with MK&M. Further work is needed to improve the equity of DHIs for people from potentially disadvantaged groups, and specific revisions to improve accessibility and engagement for these populations will be undertaken.

The design of MK&M was guided by the user-centered design principles, and the usability testing of MK&M with people living with CKD has ensured that MK&M is accessible and easy to navigate for our target population. However, the study population is fairly homogenous and not necessarily representative of the CKD population. Further work is required to explore how to improve uptake, adoption, and engagement with individuals from disadvantaged and underserved groups.

Overall, MK&M DHI was well-received and used by participants. The educational content was more widely and frequently used by participants and was perceived to be the most useful component of MK&M. The information provided was considered comprehensive, and its presentation made it easy for users to access and engage with. Our findings demonstrate that people with CKD are capable and willing to use DHIs to improve their kidney health and self-management knowledge and behaviors. Raising awareness of CKD by providing information about CKD and its management via resources such as MK&M is paramount to optimizing care and treatment and will positively impact an individual’s ability to self-manage their health. As better self-management is associated with better health outcomes and lower health care costs, MK&M has the potential to improve CKD health care management. Future trials are needed to evaluate the impact of CKD self-management DHIs, such as MK&M, on delaying disease progression, preventing progression to end-stage kidney disease, reducing cardiovascular morbidity and mortality, preventing unnecessary hospital admissions, and reducing health care costs. Findings will be used to revise the program to improve accessibility, engagement, and user experience. Further work is also required to revise and adapt MK&M to increase uptake and engagement among disadvantaged and underserved groups, who are likely to have the most to gain from using the program. In addition, the identification of real-life use and usability issues will help refine MK&M to improve the content and delivery before clinical implementation. Understanding the implementation strategies and processes required to ensure the successful delivery, reach, adoption, and sustainability of MK&M is warranted, and future implementation trials will be conducted to evaluate the translation of this research into action.