We analyzed engagement data collected during a feasibility randomized control trial of a mobile behavioral health app designed to help patients treated in primary care for chronic pain management. The feasibility trial was a 2-arm randomized controlled trial designed to assess the feasibility of trial implementation (recruitment, randomization, treatment, and retention) and explore preliminary impacts on pain, pain interference, and mental health. This paper presents a descriptive analysis of user experience and app use data among participants in the intervention arm, who had access to the mobile behavioral health app during the study period. Participants were randomized using a stratified approach based on health care system and age to ensure balanced allocation across health systems and approximate the national age distribution of adults living with chronic pain.

This study was conducted as part of a National Institutes of Health Small Business Innovation Research–funded collaboration, with 2Morrow Inc serving as the grant recipient and developer of the intervention and the University of Washington serving as the academic research partner.

All study procedures, including recruitment, consent, data collection, and follow-up, were reviewed and approved by the University of Washington Institutional Review Board (STUDY00016340) and were conducted in accordance with the approved study protocols and applicable federal regulations. All patients provided informed consent prior to participation. Patient privacy and confidentiality were protected through multiple safeguards. Data were stored on secure, access-controlled systems, and all analytic datasets were deidentified prior to analysis. No directly identifying information was included in analytic files. App use data were captured automatically through the intervention platform and linked to study data using unique participant identifiers. Data handling procedures complied with applicable privacy and confidentiality requirements. Patients assigned to the Salty program were provided with 2Morrow’s privacy policy at the time of program activation, which outlines how user data are collected, used, and protected.

Patients received a US $50 electronic gift card for each completed survey (up to US $200 total).

Primary care patients with chronic pain were identified through electronic health records at 4 health systems (60 clinics) in Washington and Idaho, sent an email invitation to participate in the study, and directed to complete a screening survey to determine eligibility. Eligible participants had at least one documented chronic pain condition identified through electronic health records. Types of pain represented in the study population included back pain, neck pain, noninflammatory joint pain, abdominal or bowel pain, fibromyalgia, and headache disorders. Patients were selected to participate if they were actively receiving care for their chronic pain (≥2 primary care visits in the previous year), currently endorsed struggling with chronic pain for 3 months or longer, endorsed having pain interference in their lives (≥55 on the Patient-Reported Outcomes Measurement Information System Pain Interference scale [21,22]), could use an app in English, and had a smartphone compatible with the behavioral health app.

Patients randomized to the intervention group received access to the Salty for Chronic Pain app, a novel digital behavioral health intervention developed by 2Morrow Inc (Figure 1). To be included in this study and analysis, patients had to successfully activate the app, which included downloading it and completing their in-app personal profile.

Patients were invited to participate via email and directed to an online interest survey. The survey provided 3 options: proceed to eligibility screening, request a call from a study coordinator for additional information, or opt out of the study. Patients who completed the eligibility screening were informed of their eligibility status at the end of the survey. Those who were eligible were directed to an electronic consent form, which allowed them to confirm participation, request further discussion with a study coordinator, or decline participation. Patients who confirmed participation provided informed consent electronically prior to enrollment.

Salty for Chronic Pain (pain app) is a 12-week self-directed program designed to educate and support patients managing the emotional, social, and behavioral aspects of living with chronic pain with the goal of reducing pain interference and improving function and quality of life. The program was created with input from patients, health care professionals, and pain behavioral health specialists during phase 1 of the Small Business Innovation Research trial; health care professionals indicated that they wanted additional options for their patients with pain that were evidence based but did not require much of their time [23].

The program used the metaphor of guiding patients on a personal journey to explore the physical, emotional, and social aspects of pain to learn how to live life despite having pain. The program included a total of 58 core lessons divided into 4 sections and additional bonus content. The first core section, known as “Hometown,” included 22 lessons related to the concept of valued living and living with pain based on principles from acceptance and commitment therapy. The other sections covered the physical (16 lessons), emotional (13 lessons), and social (7 lessons) aspects of pain.

The program included tools for gaining personal insights into pain and daily functioning. The “Daily Check-in” allowed patients to rate their overall day (“awesome” to “awful”), as well as energy, activity, stress, social connection, valued activities, and pain (all on 5-point scales), with results displayed graphically across daily, weekly, or monthly views. A journal feature was provided for recording additional reflections, and patients could optionally connect a Fitbit (provided at no cost) to track activity, sleep, and heart rate. Self-screenings were available in the “Self-Discovery” section, including the Depression, Anxiety, and Stress Scale-21 (DASS-21 [24]); Valued Living Questionnaire (VLQ; [25]); Drug Use Disorders Identification Test (DUDIT [26]); and Alcohol Use Disorders Identification Test (AUDIT [27]). Although the program was intended to be self-guided, participants could message with a coach on the app about lessons, personal discoveries, and progress. These features and others on the app are described in Textbox 1.

Each time patients opened the app, they were prompted to complete a “Daily Check-in” and up to 3 scheduled lessons and could view optional bonus content. They were encouraged to engage with the app 2 to 3 times per week over 12 weeks, with lesson access paced to discourage rapid completion and promote sustained use. All participants began with valued living content in the “Hometown” section before advancing to the “Social,” “Physical,” or “Emotional” modules. Completion of all lessons within a category was required before moving on as content was designed to build sequentially. Participants could bookmark favorite lessons and retained access to app content and features for 100 days.

Patients earned up to 12 milestone stamps (Table 1) as a gamified feature to promote engagement and track progress. Stamps were displayed on the “Passport” tab and awarded for completing the profile, core content (values, body, mind, connection, and bonus), at least 10 “Daily Check-ins,” and a monthly check-in, as well as for connecting a Fitbit, messaging a coach, completing self-screenings, and visiting all recommended sections.

Demographics (age, gender, race and ethnicity, educational level, and employment status) and pain history (type and duration) were collected at screening or baseline. Use metrics were captured from the app data system. App metrics included app use milestones achieved (eg, earned passport stamps) and use metrics, including unique days of use, duration (days between first and last use), core lessons completed, feature use (tracking and self-screenings), and in-app actions.

User experience was measured at 3 months via the mHealth App Usability Questionnaire (MAUQ [28]) and a custom perceived usefulness survey developed by 2Morrow, Inc. Acceptability and usefulness were derived from the MAUQ Ease of Use and Satisfaction Domain (Q1-8). The custom survey asked patients to rate the helpfulness of the app overall and of specific features, value, and the likelihood that they would recommend the app to others.

Recruitment, screening, and survey administration were managed by the University of Washington. Patients had 2 weeks to complete each survey.

Descriptive statistics (frequencies, means, ranges, and percentages) were calculated for demographics and engagement, describing the types of app content, features, and tools accessed.

Of the 49 patients randomized to the pain app intervention arm, 40 (81.6%) met the inclusion criteria for this study (ie, successfully activated the program by downloading the app and completing their profile). Participants reported living with chronic pain for 3 or more years; were aged 47.3 (SD 17.3) years on average (the most common age group was 30-44 years); and identified as women for the most part followed by men, with a smaller proportion (3/40, 7.5%) identifying as nonbinary. Nearly half (19/40, 47.5%) of the participants identified as White individuals, with the remainder (21/40, 52.5%) identifying as Asian, Pacific Islander, or Hawaiian; Black; multiracial; or other. Educational attainment ranged from high school to postgraduate education, with most participants (32/39, 82.1%) reporting at least some college education. At baseline, a substantial proportion of the participants reported a history of mental health conditions, reflecting the clinical complexity of the study population. Employment status varied, including part-time work, full-time employment, and disability status. Counts and percentages are reported in Table 2.

This study evaluated the Salty for Chronic Pain app, a behavioral digital health program designed to support adults living with chronic pain. Unlike most studies on digital health programs for pain that report only frequency or duration of use, our evaluation incorporated milestone completion, lesson progression, self-tracking, and perceptions of usefulness, offering a more comprehensive view of engagement and potential value as a complement to clinical care. Patients demonstrated sustained engagement for nearly a month, advanced through structured lessons, and reported high usability and satisfaction, suggesting that the program appeared feasible and was generally well received. These findings add to a growing body of research showing that digital platforms can deliver behavioral pain self-management strategies in ways that are usable, acceptable, and aligned with evidence-based approaches [10,16,23,29].

Although direct comparisons to other studies are limited due to differences in design, content, and metrics, our findings are broadly consistent with those of prior digital pain intervention research [30,31]. Activation rates were high, suggesting that patients could begin using the app with minimal support, which may help reduce burden on clinical staff. Most participants met recommended frequency targets, indicating that the app design supported regular use without intensive reminders. These results are comparable to those of Thomson et al [32], who reported that 77% of participants achieved minimum engagement during a 6-week intervention.

On average, patients completed more than 25 core lessons, and engagement extended beyond the introductory module, with a subset completing all lessons and others using bonus content. This level of engagement is noteworthy given that lessons were sequenced, requiring completion of one section before progressing, and the valued living module (“Hometown”) was mandatory before others could be accessed. In addition, no automated reminders were delivered due to a technical issue. Hence, engagement occurred without automated reminders, suggesting that participants were self-motivated. It is possible that greater use would have been achieved with automated reminders or more flexible sequencing. At the same time, these findings raise important questions about how much content exposure is necessary to achieve meaningful improvements in pain, acceptance, and functioning. Some patients may benefit from a targeted subset of lessons, whereas others may require more extensive exposure. Clinical outcomes will be reported separately. Future refinements, such as adding flexible sequencing or automated prompts, may increase completion rates and help identify the “dose” of content most strongly associated with clinical benefit or perceived value.

These findings highlight the potential of digital behavioral health tools to support access to evidence-based pain self-management strategies. Participants engaged with structured lessons and interactive features that promoted reflection, self-monitoring, and awareness of valued living—processes associated with acceptance, coping, and resilience in chronic pain populations [33,34]. The results suggest that such strategies can be delivered in digital form with high usability and satisfaction; however, engagement metrics reflect exposure to content rather than therapeutic dose or clinical effect.

Several limitations should be considered when interpreting these findings. The relatively small sample size reflects the feasibility nature of the trial and limits generalizability to all adults with chronic pain. The eligibility criteria and study context further shape interpretation: participants were required to have smartphone access, English-language proficiency, and clinically significant pain interference, and most reported long-standing pain. Accordingly, the sample may overrepresent individuals who were digitally ready or motivated to engage with a self-directed program. The engagement patterns observed in this study may not generalize to all adults with chronic pain, particularly those with limited digital access or differing readiness to engage in behavioral interventions.

Taken together, these findings suggest that this type of digital behavioral health program may be particularly well suited for individuals who are motivated to engage in self-directed care and interested in nonpharmacologic or complementary approaches to chronic pain management. The observed engagement without automated reminders further suggests potential fit for users who prefer flexible, low-burden support delivered outside traditional clinical settings.

Engagement and satisfaction ratings may have also been influenced by study participation, incentives associated with survey completion, novelty effects, or app design constraints such as fixed lesson sequencing.

Despite these limitations, this study provides early evidence that an evidence-informed, user-centered mobile program can be feasibly delivered and meaningfully engaged with by adults receiving care for chronic pain. These findings can inform intervention refinement and support the design of larger studies to evaluate engagement patterns; predictors of sustained use; and effects on pain interference, functioning, and quality of life [17,18].

Patients successfully activated the program without support, most met recommended use targets, and many engaged deeply with the available content and insight tools. These findings are promising for the use of self-directed evidence-based digital behavioral health apps in clinical pain management. While patients rated the features favorably, additional research is needed to determine how much exposure is necessary to achieve clinical benefit. Future studies should evaluate the impact of these tools on pain interference and functioning, identify engagement patterns linked to improved outcomes, and test refinements such as flexible sequencing or automated reminders. Addressing these questions can help digital behavioral health programs expand access; supplement usual care; and support more equitable, scalable approaches to chronic pain management.