About 18.2% and 21.4% of adults reported symptoms of anxiety and depression, respectively [1]. These conditions are often undertreated, partly due to many obstacles prohibiting treatment initiation and engagement, resulting in a substantial unmet need for effective and accessible mental health interventions [2]. Among underserved populations are adults with physical disabilities or functional limitations, who comprise a large proportion of the US population, with over 40% of those aged 45 to 64 years reporting such limitations, a 21% increase in prevalence from 2002 to 2016 [3]. This growing population faces compounded barriers to care, including limited access to evidence-based therapies, highlighting the critical need for scalable interventions tailored to both mental health and functional challenges. Additionally, this population is at higher risk of mental health difficulties than those without a disability, with recent data showing that 32.9% of those with disabilities report significant mental distress as compared with 7.2% of those without disabilities [4].

Unfortunately, individuals with disabilities and functional impairments also face significant barriers in accessing adequate treatment, including limited treatment options, a lack of adequate training among providers concerning the unique needs of those with disabilities, and limited transportation capabilities [5,6]. Further worsening this public health problem is a severe shortage of mental health providers. On average, within the United States, only 26.4% of all mental health care needs are being met based on provider volume and availability [7]. These provider shortages strongly contribute to the 2023 finding that 46% of US adults with a mental disorder did not receive care for their condition [8].

Fortunately, evidence suggests that these obstacles are surmountable. For example, research has shown that cognitive behavioral therapy (CBT) and mindfulness-based therapies are strong approaches for this population [9-11]. Furthermore, virtual mental health interventions for those with disabilities can address obstacles related to mobility or transportation [12,13], reduce wait times, and increase overall access [14-16]. Self-guided CBT has shown significant promise in treating adults with mild-to-severe mental health symptoms without requiring a licensed provider [17,18].

In response to the rapid expansion of digital health technologies, the digital therapeutics (DTx) category has emerged as a distinct class of evidence-based interventions. Although definitions vary, DTx is largely characterized as a digital, evidence-based medical intervention delivered directly to patients to prevent, treat, or manage a disease or disorder using validated clinical frameworks [19]. As it relates to mental health, DTx and closely related evidence-based digital interventions demonstrate significant promise in reducing symptom severity across multiple conditions [20-24]. However, there are notable limitations, including high rates of attrition [25], often attributed to symptom severity beyond the scope of self-guided DTx capabilities, technological limitations, and insufficient personalization or support [26,27]. Importantly, evidence suggests that attrition can be reduced and adherence improved through the inclusion of human support elements that enhance accountability, personalization, and timely response to changes in treatment needs [28,29]. However, despite their promise, many existing digital platforms remain inadequately accessible for individuals with disabilities, inadvertently reproducing the very barriers they aim to reduce [26,30]. As such, designing DTx in alignment with established accessibility standards, such as the Web Content Accessibility Guidelines (WCAG) 2.2 [31], is therefore not a peripheral design consideration but a foundational requirement for equitable delivery of evidence-based care.

Beyond digital solutions, another step in expanding mental health care has been the significant increase in health and wellness coaches, such as National Board-Certified Health and Wellness Coaches (NBC-HWC). Health and wellness coaches are professionals who support patients in making behavioral changes according to self-chosen health goals and needs [32]. In terms of efficacy, a recent meta-analysis supports the use of health and wellness coaches as a stand-alone behavioral intervention in improving mental health outcomes among those with medical and psychological conditions [33]. In addition, adding a health coach to self-guided CBT significantly improves mental health outcomes over and above self-guided CBT alone [34]. At a systemic level, the use of health and wellness coaches is a promising avenue for improving flexible access to mental health care, given that these sessions are significantly shorter than traditional psychotherapy, typically around 30 minutes [32,35], allowing for more patients to receive care per single coach when compared to licensed mental health providers.

In summary, although adults with disabilities face significant mental health concerns and obstacles to accessing adequate care, ongoing innovations in technology, treatment delivery, and types of care show promising results in better reaching and treating this underserved population.

Rauha is a smartphone-based DTx developed to deliver flexible, accessible, and evidence-based mental health care for adults with anxiety-related and depression-related symptoms, including those with functional or sensory limitations. The Rauha DTx is a Health Insurance Portability and Accountability Act (HIPAA)–compliant software, certified with WCAG 2.2 AA accessibility standards. This certification ensures usability for individuals with functional, sensory, or other accessibility challenges, as only 5.2% of the top 1 million websites pass WCAG accessibility testing [36]. Per WCAG principles, Rauha is perceivable, operable, understandable, and robust [31]. Therapeutic content is delivered across text, audio, and video, with captions, transcripts, and high-contrast scalable text to support perceivability. The platform allows full keyboard navigation and works with assistive technologies, avoiding reliance on time-sensitive interactions. Content is written in plain language and presented in a consistent, structured format. The system was tested across devices and browsers and designed to work with common accessibility tools.

The clinical program of Rauha consists of 2 integrated components: (1) asynchronous, self-guided, interactive modules and exercises rooted in standard CBT [37], delivered digitally via recorded sessions by a licensed psychologist, allowing users to listen, review, and engage with content multiple times at their convenience; and (2) weekly live virtual coaching sessions with an NBC-HWC focused on implementing evidence-based behavior change strategies to support patients’ chosen goals. The use of NBC-HWCs rather than licensed therapists was intentional to support scalability, expand access to care, and align the live treatment component with a structured behavior change model that complements the asynchronous CBT content.

This clinical program is meant to serve as an intermediary treatment option, balancing the benefits of both self-guided, smartphone-based CBT programs and traditional one-on-one care offered by clinicians (Table 1). Traditional psychotherapy is often constrained by provider availability and extended wait times [38,39], whereas self-guided CBT offers immediate access but may be limited by engagement and adherence challenges [40], as well as rarely, if ever, meeting WCAG standards [41]. Hybrid models that combine digital content with human support can address these limitations by maintaining scalability while incorporating structured support, which has been associated with improved engagement and more efficient use of clinical resources [42].

The central aim of this study was to evaluate Rauha in the treatment of moderate-to-severe symptoms of anxiety and depression in adults with a hearing and/or mobility-related disability. We hypothesized that there would be (1) at least 80% treatment retention among those who initiated the intervention and (2) a statistically and clinically significant reduction (CSR) in anxiety and depressive symptoms between baseline and the end of the treatment period through a 4-week follow-up. As an exploratory aim, we assessed user acceptability, experience, and usability of the Rauha program.

This study used a single-arm, within-participants design to measure the clinical impact of Rauha on symptoms of anxiety and depression, as measured by the Hamilton Anxiety Rating Scale (HAM-A) [43] and Hamilton Depression Rating Scale (HAM-D) [44], respectively. Patients were assessed with the HAM-A and HAM-D at baseline (preintervention), immediately after completing treatment (post intervention), and 4 weeks after completing treatment (follow-up). Participation from baseline to follow-up lasted approximately 12 weeks.

Participants were recruited through approved study flyers at Endeavors Programs in San Antonio, Texas, as well as through other approved recruitment channels, including clinical and community referrals. Inclusion criteria for participation were a self-reported mobility or hearing disability, age 22 years or older, a minimum score of 10 on the Patient Health Questionnaire-9 (PHQ-9) [45] or Generalized Anxiety Disorder-7 (GAD-7) [46], access to a stable internet connection via Wi-Fi or mobile data, access to an iPhone or iPad (optionally, an iPhone could be provided by the research team), English fluency, resident of the United States for the duration of the study, no changes in psychotropic medication or psychotherapy treatment in the 30 days before study entry, and comprehension of and willingness to sign informed consent and complete all study procedures.

Exclusion criteria were a diagnosis of psychotic or bipolar disorder, active participation in another treatment trial, nontobacco substance use disorder within the past 12 months, any suicidality beyond passive ideation in the past 12 months, and currently pregnant or planning to become pregnant during the treatment period.

This study was approved by the Advarra Institutional Review Board (Protocol 79652). All participants provided informed consent prior to participation in any study-related activities. Participation was voluntary, and participants were informed that they could withdraw from the study at any time without penalty. Participant privacy and confidentiality were protected throughout the study. All study data were collected, transmitted, and stored within a HIPAA-compliant digital platform and secure data management dashboard with restricted access limited to authorized study personnel. Appropriate administrative, technical, and physical safeguards were implemented to protect participant information. Data were deidentified prior to analysis and reporting. Participants received US $125 in compensation for their participation in the study in accordance with the institutional review board–approved protocol and were not contingent upon study outcomes.

A total of 37 individuals were assessed for eligibility, of whom 14 were excluded for not meeting inclusion criteria. Twenty-three participants provided informed consent. Of these, 10 did not initiate the intervention: 1 declined to participate and did not complete baseline HAM-A or HAM-D assessments, and 9 elected not to continue due to preference for live clinician therapy, time-commitment requirements, discomfort with recorded sessions, or inability or unwillingness to complete the intervention on an iOS device. The remaining 13 participants initiated and completed the intervention, with no attrition during treatment, and all 13 completed the post treatment assessment. At follow-up, 12 participants completed the follow-up assessment, with 1 participant declining follow-up participation. Participant flow of the study is shown in Figure 1 (CONSORT [Consolidated Standards of Reporting Trials] diagram), detailing screening, enrollment, intervention initiation and completion, post treatment assessment, and follow-up assessment.

The final analytic sample consisted of 13 adults, of whom 53.8% (n=7) were female participants and 46.2% (n=6) were male participants. Reporting of age and race or ethnicity was optional; 12 of 13 participants reported age and 9 of 13 reported race or ethnicity. Among those reporting age, the mean age was 34.42 (SD 13.51) years. Of the 9 participants reporting race or ethnicity, 5 identified as White, 2 as two or more races, 1 as Hispanic, and 1 as Black or of African descent. With respect to disability status, 6 participants reported a mobility-related disability, 2 reported a hearing-related disability, and 5 reported both mobility-related and hearing-related disabilities. Based on baseline HAM-A and HAM-D scores, 10 participants exhibited clinically elevated levels of both anxiety and depression, 2 exhibited elevated depression only, and 1 participant did not demonstrate clinically elevated anxiety or depression despite meeting inclusion criteria. No participants endorsed any suicidal symptoms.

Table 2 provides descriptive statistics for HAM-D and HAM-A at our 3 assessment points.

Individual spaghetti plots are illustrated in Figure 2 for HAM-D and in Figure 3 for HAM-A. Both figures illustrate 2 major findings in our study: (1) the majority of participants improved over the observational period and (2) the completeness of the data, where all participants except 1 (ID=68, who did not provide follow-up assessment) completed all 3 assessments. Figure 4 illustrates the mean profile over time for both anxiety (HAM-A) and depression (HAM-D).

With respect to anxiety, we observed a significant average reduction of 11.84 (SE 2.44) from baseline (mean 21.69, SD 9.35) to post treatment (mean 9.85, SD 8.90; t₁₃=4.85, P<.001). From post treatment (mean 9.85, SD 8.90) to follow-up (mean 9.00, SD 7.01), we observed a nonsignificant reduction of 1.24 (SE 2.51; t₁₃=0.48, P=.64). Cumulatively from baseline (mean 21.69, SD 9.35) to follow-up (mean 9.00, SD 7.01) for anxiety, we observed a significant average reduction of 13.05 (SE 2.51; t₁₃=5.21, P<.001), corresponding to a mean shift from moderate to mild anxiety between baseline and follow-up. Partial η estimates quantifying the size of the effect for the change from baseline to post treatment and follow-up were η²_p=0.80 (95% CI 0.48-0.90) and η²_p=0.82 (95% CI 0.52-0.91), respectively, corresponding to large effects. Similarly, for depression, we observed a significant average reduction of 12.39 (SE 1.50) from baseline (mean 19.92, SD 5.14) to post treatment (mean 7.54, SD 6.63; t₁₃=8.24, P<.001). From post treatment (mean 7.54, SD 6.63) to follow-up (mean 7.17, SD 5.36), we observed a nonsignificant reduction of 0.44 (SE 1.55; t₁₃=0.29, P=.78). Cumulatively from baseline (mean 19.92, SD 5.14) to follow-up (mean 7.17, SD 5.36), we observed a significant average reduction of 12.83 (SE 1.55; t₁₃=8.30, P<.001), corresponding to a mean shift from moderate to mild/nondepressed between baseline and follow-up. Partial η estimates quantifying the size of the effect for the change from baseline to post treatment and follow-up were η²_p=0.92 (95% CI 0.76-0.95) and η²_p=0.92 (95% CI 0.76-0.96), respectively, corresponding to large effects.

Based on published research, we define CSR as a 4-unit change in both HAM-A [63] and HAM-D [64]. Using all 13 participants, with nonresponse corresponding to not achieving CSR, at post treatment, 84.6% (95% CI 54.5%-98.0%) achieved CSRs for both anxiety and depression. At follow-up, 76.9% (95% CI 46.2%-95.0%) achieved a CSR in anxiety and 92.3% (95% CI 74.0%-99.0%) in depression. Interestingly, 1 participant (ID=8) started the study without an elevation in the HAM-A or HAM-D but still displayed a CSR in both. As CSR can depend on initial measurement score, the percentage of participants achieving a symptom reduction ranging from 10% to 90% (in 10% increments) from baseline to post treatment and baseline to follow-up are shown in Tables 3 and 4, respectively.

Figure 5 summarizes the acceptability, experience, and usability of the Rauha smartphone platform. Among participants who agreed or strongly agreed based on direct DTx experience, 85.6% (SD 10.4%) reported positive acceptability, 87.7% (SD 8.3%) reported positive experience, and 85.0% (SD 6.3%) reported positive usability. The most highly endorsed items (>90%) highlight the aspects of the program driving the positive user experience: overall satisfaction with the treatment program, relevance of treatment strategies to daily life, the central role of mental health coaches in treatment success, use of video and text delivery within Rauha, ease of understanding digital content, and confidence in using the platform. Importantly, there was no negative feedback on any item across these self-report surveys and no accessibility issues, given the WCAG 2.2 AA standards of the smartphone program. These findings underscore that participants valued not just general satisfaction but specific program components that supported engagement, skill application, and confidence in using Rauha effectively.

Regarding replay rate, participants revisited previously completed CBT lessons multiple times over the course of the intervention, with an average replay rate of 5.5. Replay behavior was derived from platform usage analytics, with some modules showing higher repeat access based on user interaction patterns (eg, repeated entry and time spent within lessons). In the context of consistently high acceptability, experience, and usability ratings, this pattern of re-engagement is more consistent with voluntary reuse of content than with difficulty understanding the material.

The central aim of this study was to evaluate Rauha—a mental health DTx intervention combining an asynchronous, CBT-based treatment with a synchronous NBC-HWC implementing behavior change strategies—in treating symptoms of moderate-to-severe anxiety and depression in adults with hearing and/or mobility-related disabilities. We hypothesized that (1) there would be a treatment retention rate of at least 80%, and (2) there would be a CSR in internalizing symptoms from pretreatment to post treatment and through follow-up. The data supported both hypotheses, with a retention rate of 100% and a statistically and clinically significant decrease in both anxiety and depression symptoms on average that was sustained during the 4-week follow-up. Furthermore, this average decrease in symptoms far exceeded the minimum threshold for clinical significance by a magnitude of 3, such that participants had even more benefit than expected.

This is the first known study to assess the treatment effect of a WCAG 2.2 AA–certified platform-aligned DTx combined with a weekly, virtual NBC-HWC to treat moderate to severe symptoms of anxiety and depression in adults with disabilities. In addition, as noted previously, 1 participant with subclinical baseline levels of both anxiety and depression nevertheless achieved a CSR despite a generally lower capacity for symptom change among those with lower baseline severity [9]. Given these results, this study offers strong preliminary data to support this novel approach to treatment. In addition, the 100% retention rate also speaks to the acceptability and engagement of the treatment itself, given that treatment retention is often an issue both in research [65] and clinical [66] settings. These findings extend the overall evidence of CBT-based interventions to less-used treatment modalities while also being applied to an underserved clinical population, adults with disabilities and functional limitations. The clinically significant outcomes from this study are either commensurate with or exceed many previous outcome studies, including internet-based CBT [18,67,68], traditional CBT delivered as weekly individual therapy [69-71], combined internet-based and individual face-to-face CBT [70,72-74], and CBT combined with pharmacotherapy [75].

At a systems level, and as it relates to barriers prohibiting access to adequate treatment, both of the Rauha treatment components can increase overall access to care, as self-guided treatment does not require time from a provider for a patient to receive care, and there are over 12,000 NBC-HWCs that can be considered part of the otherwise limited mental health resources to drastically expand treatment options [76]. Thus, CBT and other evidence-based approaches can be highly scaled with this approach without sacrificing clinical impact.

This study has several notable strengths. First, it evaluated a novel, digitally delivered CBT intervention targeting an underserved population with nuanced physical and mental health needs, addressing a critical gap in accessible mental health care. These findings extend our understanding of the potential for nontraditional treatment modalities and suggest that CBT can remain clinically impactful even when delivered through a smartphone-based DTx. Second, the use of clinical significance, in addition to statistical significance, provides a richer assessment of treatment impact, highlighting the clinical meaningfulness of Rauha for patients. Third, the inclusion of a 4-week postintervention follow-up allowed for a preliminary assessment of the durability of symptom improvements. While this time frame provides early support for the maintenance of treatment effects, longer follow-up periods are needed to fully characterize sustained outcomes in anxiety and depression. Interestingly, there was an increase in clinically significant improvement in depression between post treatment and follow-up, which may be attributable to participants having continued access to the smartphone-based CBT program to revisit relevant clinical content, though the robustness of such a finding would require further research. Finally, assessing user acceptability, experience, and usability offers greater insight into the participant’s experience with the DTx, demonstrating highly positive views regarding the ease of use, DTx content, and coaching sessions. Together, these elements underscore the potential of Rauha as a scalable, accessible, and evidence-informed treatment.

This study has several limitations that should be considered when interpreting the findings. First, the sample size was small, which limits statistical power, the precision of estimates, and the generalizability of findings. Accordingly, the observed large effect sizes should be interpreted with some caution and considered preliminary support for proof-of-concept requiring replication in higher-powered clinical studies. Second, the participant population was limited to individuals with hearing and mobility disabilities, and researchers allowed certain demographic disclosures to be optional for participant comfort. Future efforts could expand representation across a broader range of functional and accessibility challenges and require demographic reporting, which would enhance generalizability. Third, the study did not include a control condition, which limits formal causal inference such that results may reflect uncontrolled factors (eg, natural symptom fluctuation, placebo effects, regression to the mean, or untracked changes in medication during the intervention). Given this, future studies incorporating a control condition are planned to rigorously assess causal treatment effects. Fourth, participants were recruited in part through a mental health clinic, which may introduce selection bias, as the individuals referred may differ from the broader population in terms of treatment readiness, clinical profiles, and motivation to engage in care. Future studies can address this by using more diverse recruitment strategies to strengthen generalizability. Finally, because Rauha combines a self-guided digital component with NBC-HWC support, it is not possible to attribute the observed outcomes to either component alone. That is, the present design does not allow for attribution of effects to either the digital CBT component or the coaching component independently. Future studies using component analyses or factorial designs are needed to isolate the mechanisms of change and optimize the intervention itself by identifying the most impactful factors. Collectively, these limitations highlight the need for continued research while underscoring the promising potential of Rauha to improve outcomes in this population.

To our knowledge, this is the first study to evaluate a hybrid digital CBT intervention—combining self-guided, smartphone-delivered CBT with live weekly sessions led by a NBC-HWC—for adults with disabilities experiencing anxiety and/or depression. The findings provide preliminary support for clinical benefit of Rauha, high engagement, accessibility, and scalability, while identifying important directions for future research. Importantly, this work supports the potential of a coordinated digital CBT and coaching model to address persistent barriers to care and deliver flexible, clinically meaningful support to populations historically underserved in mental health services. Overall, Rauha represents a promising, evidence-informed approach that extends the reach of CBT and highlights the value of integrating DTx with coaching to improve mental health outcomes among adults with functional and accessibility challenges.