Using a concurrent parallel mixed methods design [46], this study included a cross-sectional, web-based survey of a national panel of oncology dietitians and semistructured interviews with survivors with HNC and caregivers. We selected a mixed methods approach to facilitate gathering the perspectives of three groups, including dietitians, survivors with HNC, and caregivers [46]. A mixed methods approach also allowed for a more comprehensive understanding of the unmet needs of caregivers of people with HNC to drive the selection of content in a supportive care app to address those needs. Our team included researchers with expertise and training in HNC, cancer survivorship, oncology caregiving, and mobile health. We used a team approach to reflexivity with discussion and attention to the potential of the research team’s background to influence research findings.

The purpose of this mixed methods study was to characterize nutritional challenges and caregiving tasks and intervention preferences in HNC oncology dietitians (quantitative) and survivor-caregiver dyads (qualitative and quantitative). We concurrently collected survey data from dietitians. Both quantitative and qualitative data were considered of equal priority and were analyzed separately and then integrated using the merging technique [47] as described below. Data were collected between April and September 2018. The GRAMMS (Good Reporting of A Mixed Methods Study) checklist was used to guide the mixed methods approach and reporting [48] (Checklist 1). Multimedia Appendix 1 provides the interview guide and surveys.

A convenience sample of dietitians was recruited by posting a study notice on the listserv for the Oncology Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics. Dietitians were eligible for the 15-minute web-based survey if they reported providing care for patients with HNC in the past 6 months; the survey was hosted on REDCap (Research Electronic Data Capture; Vanderbilt University). The 67-item survey was developed by the study team. All items were optional, and participants could return to the survey over time if requested. The survey assessed demographic (race, ethnicity, sex, and age) and practice (credentials, years practicing as a dietitian, practice setting, and number of patients with HNC seen per week) characteristics. In addition, perceptions of the importance of posttreatment concerns in caregiving (0=not at all important to 4=extremely important) and perceived importance and difficulty (0=not important or difficult at all to 4=extremely important or difficult) of a variety of support tasks for caregivers of people with HNC, guided by the transactional model of caregiving were assessed (eg, tracking nutritional intake, changes and patterns in symptoms, and making care decisions [49]). Other measures included ratings of nutritional support resource needs (0=not at all to 4=extremely) in caregivers of people with HNC (eg, screening process to identify caregiver nutritional concerns, assessment tool to identify caregiver distress, and educational materials) and barriers to addressing support needs (1=not a barrier at all to 4=major barrier) in caregivers of people with HNC (eg, time, caregiver interest, lack of evidence about the value of caregiver programs, and leadership). Participants then reviewed example app screens and then answered questions about the preferred focus of app content (eg, increasing caregivers’ awareness of the importance of addressing nutritional challenges, changing caregivers’ attitudes about improving nutritional status, and encouraging help-seeking for nutritional support) using an adapted version of the app-specific subscale in the Mobile App Rating Scale [50] (1=strongly disagree to 6=strongly agree) and an open-ended question. Finally, participants completed an open-ended question asking them to describe any specific suggestions they had for the development of a mobile support app for HNC caregivers.

Survivors with HNC who completed treatment with curative intent 6‐24 months prior to enrollment and were free of disease, and their caregivers, were recruited at the Medical University of South Carolina Hollings Cancer Center, with initial screening for eligibility by chart review. Inclusion criteria included being 18 years or older, completing treatment for stage I-IVA HNC (mucosal squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, and larynx), and experiencing nutritional challenges at the end of treatment as assessed by a 6-item screen. Survivors were excluded if they were unable to identify a primary caregiver, and survivors and caregivers were excluded if they either did not speak English or were cognitively impaired. After mailing a study letter and determining eligibility via phone screen, dyadic interviews were scheduled. Informed consent documents were signed, and dyadic interviews were conducted in person by 2 female investigators with training in qualitative methods (KS and MS). Interviewers did not know the participants and were not involved in their clinical care. Interviews were continued until we reached saturation in themes [51]. They were conducted in a private room, audio-recorded, and lasted approximately 45 minutes. Field notes were taken to provide interview observations.

We developed a semistructured interview guide using a cancer survivorship quality of life framework [52] to examine participants’ reflections on the physical, emotional, and social challenges they experienced at the end of treatment and in the 6 months following treatment conclusion, with an emphasis on nutritional challenges and caregiving. Survivors and caregivers were asked to describe their emotional and physical well-being at the end of treatment. They were asked specifically about nutritional challenges, expectations they had about intake abilities, and the caregiver’s role in nutritional recovery. Finally, they were asked about caregiver needs and suggestions for resources to better meet their needs at the end of treatment. Participants then viewed a set of example app screens (eg, nutrition tips, recipes, and stress management advice) on a tablet, after which they provided feedback on the content and format of a future app. After the interview, survivors and caregivers completed separate brief paper-based surveys assessing demographic (age, race, sex, and education), clinical (stage, treatment type, and nutritional status at the end of treatment), and technology access (home computer and smartphone) characteristics. They also completed ratings of the importance of caregiving tasks (0=not important to 4=extremely important) and ratings of agreement (1=strongly disagree to 6=strongly agree) about the benefits of checking in with caregivers after treatment, providing support messages to caregivers, and the importance of providing practical information to help with patients’ nutritional recovery.

Study procedures were approved by the Medical University of South Carolina Institutional Review Board (Pro00066211). A waiver of written informed consent was granted for dietitian surveys; after reading a study statement, participants advancing to the survey implied consent. Dyads completed written informed consent before completing interviews and received a copy of the signed consent for their records. All screening and survey data were stored in password-protected databases. The underlying databases were hosted in a secure data center. All data were identified only by code number (participant IDs). Dietitians completing surveys were entered into a lottery to receive a US $25 gift card to thank them for their time. Survivors with HNC and caregiver participants each received a US $50 gift card.

Descriptive statistics were used to characterize survey data on dietitian and survivor-caregiver dyad demographic characteristics, perspectives about posttreatment, and caregiving challenges, and app preferences using R (R Core Team) [53]. Interviews were transcribed and analyzed using rigorous content analysis methods for systematic theme identification [54] in NVivo software (QSR International) [55]. Transcripts were coded by pairs of independent coders (KS, JO, and HK) and regrouped and reorganized until the investigators agreed on categories. This initial inductive theme identification process was followed by team meetings to finalize themes and guide implications for the intervention design. We sought trustworthiness in the qualitative data analysis approach by including prolonged engagement with the data, triangulating data, and using an audit trail to finalize themes [56]. Quantitative and qualitative data were analyzed separately, and then a data synthesis integration step was used to guide app development [57]. We selected the mixed methods integration approach of merging [47] and brought our quantitative and qualitative results together for elaboration. For example, the quantitative results (eg, perceptions and preferences of dietitians, survivors, and caregivers) were merged with key themes identified in interviews used to offer a more in-depth understanding of appropriate content for the app. Our interdisciplinary team of HNC clinicians, researchers, and developers completed a set of planning meetings to translate study results into app content by discussing the meaning of themes, identifying potential similarities and differences across themes, and mapping the themes to content using a consensus-based approach. The app development method was an agile approach, specifically rapid application development or rapid application building, which focuses on timely delivery in a fast-paced environment with the use of prototyping and iterative development [58]. The research team worked closely with the development team to review and test evolving prototypes; a final prototype was pretested with 2 caregiver volunteers who were not involved in interviews or development activities.

Dietitians endorsed caregivers’ time constraints (100/116, 86%) and caregivers being overwhelmed (102/116, 88%) as major barriers to meeting caregivers’ needs. They also endorsed oncology clinics lacking designated staff to coordinate caregiver resources (70/116, 60%), higher priority care issues (n=72/116, 62%), and clinical team time constraints (n=70/116, 60%) as barriers. In light of unmet needs and to better support caregivers’ provision of quality nutritional support to survivors with HNC, dietitians rated the importance of a variety of services and resources. While all 8 proposed services were rated by the majority (≥60%) of dietitians as very or extremely important, the highest ranked services or resources included a clinic referral process to link caregivers to appropriate nutritional resources (104/116, 90%), educational materials about diet (92/116, 79%), one-on-one counseling about nutrition (103/116, 89%), and training in nutritional support and symptom management (90/116, 78%).

Dietitians’ responses to an open-ended question after reviewing example app screens yielded suggestions for new app content, including recipe recommendations, intake tracker, encouragement about caregiving tasks, and support for the caregiver’s own well-being. Exemplary quotes include:

Survivors and caregivers’ survey responses indicated that dyads were in strong agreement that checking in with caregivers after survivors complete treatment (12/15, 80% and 9/11, 82%, respectively) and providing support messages to caregivers (11/15, 73%, and 10/11, 91%, respectively) would be helpful. In addition, dyads were in strong agreement that it is important to provide practical information to caregivers to help survivors’ nutritional recovery (15/15, 100%, and 10/11, 91%, respectively).

Feedback from dyads’ responses to open-ended questions after reviewing example app screens included keeping the content simple, providing tips about what foods to avoid, providing recipes and dynamic nutrition information as needs change, including tips from other survivors with HNC and caregivers, and emphasizing support for caregiver well-being and self-care. Examples of exemplary quotes include:

Building on results from all surveys and interviews underscoring the high need and interest in a comprehensive caregiver app, we designed the Healthy Eating and Recovery Together (HEART) app. The overall goal of the app was to support caregivers of survivors with HNC as they transition to the home setting after completing treatment and decrease their unmet needs and caregiver burden. The study investigators evaluated qualitative themes from dyad interviews side by side with quantitative themes observed in dietitian and dyad surveys. Team meetings were used to identify similarities in themes that were translated to high-priority main menu domains and subdomains for the app. The integration of survey and qualitative data resulted in an expansion of the findings, as the qualitative themes provided a detailed understanding of quantitative findings about caregivers’ unmet needs and responsibilities as caregivers. The research team worked closely with the development team to review and test evolving prototypes, and a final prototype was pretested with 2 caregivers. The app was updated with feedback over the course of these steps (eg, we updated icons, modified menu choices, added instructions to components, reordered messages, and modified color choices). HEART includes educational information, caregiving tips and encouragement, and resources, with 4 elements, including survivor nutritional support, intake tracker, caregiver toolkit, and support videos (Table 1 provides more detailed descriptions and sample screenshots). The app also provides caregivers with notifications twice a week to check in with them about their concerns and deliver real-time resources mapped to current concerns. Two main areas in the app’s content included a focus on survivor-caregiver teamwork and support of caregivers’ own well-being.

Survivors with HNC and their caregivers face exceptionally difficult posttreatment concerns that negatively impact their quality of life [28,59-61]. Caregivers are often tasked with addressing survivors’ nutritional challenges in the home setting, yet many are unprepared for these caregiving tasks [20,24]. Getting adequate nutritional intake, maintaining a healthy weight, and managing physical symptoms and emotional distress are imperative for survivors of HNC during the posttreatment period; yet, there is a paucity of tools available to support survivors and their caregivers in meeting these goals [31,32]. This study addressed this important survivorship care gap, specifically the availability and accessibility of high-quality interventions to support nutritional caregiving. Recognizing the value of stakeholder input in intervention development [62-64], we used mixed methods to assess the perspectives of survivors, and then also used responses from caregivers and oncology dietitians to guide the development of an app to support caregivers at the end of treatment. Previous studies have emphasized the acceptability of apps for cancer caregivers while also calling for more formative research to ensure their suitability [43,44,65,66]. While we intended to focus this tool on nutritional caregiving support, study results led to a more comprehensive product focused on nutrition and other survivor recovery concerns, plus caregiver self-care. The final HEART app includes nutrition support with an intake tracker, along with tips and encouragement for other caregiving areas (daily support, emotional support, and medical support), support videos from peers and clinicians, and a caregiver toolkit (taking care of yourself and relaxation exercises).

To guide app development, dietitians provided their perspectives on caring for and supporting HNC dyads. They endorsed a broad array of important nutritional concerns for HNC caregiving, including swallowing, feeding tube management, weight maintenance, and caregiver distress about nutrition. They also perceived that there were multiple nutritional care tasks that were important to survivors’ recovery, including monitoring nutrition, making care decisions, and working together with their survivors as a team to manage nutritional concerns. While most dietitians did not rate these care tasks as extremely difficult for caregivers to manage, the number of tasks endorsed was substantial, and the importance to survivors’ recovery was rated highly, indicating that an app intervention would likely need to be complex and cover a comprehensive set of nutritional concerns. These results suggest that an app should help caregivers be flexible and skilled in multiple nutritional care tasks. Additionally, dietitians’ perceptions regarding potential survivor-caregiver mismatch on nutritional goals were consistent with previous studies [18,26], which may suggest that a focus on teamwork in dyads would be beneficial in an app [67,68].

HNC survivor-caregiver dyads in this study confirmed the challenges reported by dietitians in both surveys and interviews. First, survey results highlighted similar nutritional caregiving concerns after treatment in survivors, caregivers, and dietitians. Second, interviews confirmed the types of nutritional challenges experienced and the emotional toll they take on dyads, consistent with previous studies [5,6,69,70]. Results also highlighted that nutritional caregiving tasks were compounded by other competing HNC recovery concerns (eg, support for pain, mobility, pain, fatigue, and emotional challenges); it was difficult for caregivers to focus on nutrition without considering these additional concerns. As highlighted in previous research, caregivers take on a multitude of caregiving tasks and need resources matched to these responsibilities [14,19,20], again supporting the coverage of a broad array of HNC caregiving [20] content in an app.

Dietitians also endorsed high barriers to meeting caregiver needs, including clinician time constraints and a lack of designated staff to coordinate resources. While increasing research has prioritized interventions to meet caregiver needs [31,71], cancer care settings are not adequately resourced to address their needs [72,73]. Technology tools such as the HEART app may be a promising approach to address these barriers and complement other interventions to support caregivers [39,74]. Dietitians in this study endorsed a broad variety of strategies and content to include in an app to support caregivers. Dietitians tended to prefer high-resource strategies for inclusion in an app, such as intake tracking, training, screening processes, educational resources, and counseling. Survivors and caregivers confirmed interest in an app for caregivers with check-ins, support, and practical tips. Both dietitians and dyads recommended the provision of recipes and support for caregivers’ own well-being. Dietitians uniquely recommended an intake tracker, while dyads uniquely recommended tips from peers.

While mobile health intervention development and testing to support caregivers of people with cancer is growing and shows evidence of promising acceptability, adherence, and some improvements in short-term outcomes such as caregiver burden [41-43,45,65,75,76], more research is needed in this area to better understand caregiver adoption and engagement in these interventions, impacts on caregiver psychosocial and health outcomes, and best practices for disseminating such intervention in practice using rigorous methods. Of key importance, few studies have focused on HNC caregiving and nutritional support. Apps to support caregivers of people with HNC also have the potential for supporting and addressing HNC dietitian time constraints by supporting their recommendations outside of the clinic; more research is needed in this area.

The strengths of this study include its mixed methods approach with data collection from multiple perspectives, including those who had experienced HNC recovery, served as an HNC caregiver after treatment, and provided clinical care for HNC survivor-caregiver dyads. The integration of survey data and qualitative data allowed for the examination of similarities and unique findings across qualitative and quantitative themes, ultimately allowing a deeper understanding of perspectives to guide the HEART app. Dietitians were recruited from across the United States, and qualitative interviews with dyads were used to supplement surveys and provide a more in-depth understanding of survey results. The app’s focus on nutritional support, particularly after the end of treatment, is innovative and would help address an area of major concern for HNC providers, survivors, and caregivers. In the context of changing digital health use patterns over time, it is important to note that an important limitation of this study is that the data were collected in 2018. However, it is notable that digital health use and engagement rates have increased over time, and this expanded reach and growing societal acceptance of these tools are therefore encouraging [77]. Other limitations of this study include recruitment of dyads from only one medical center, recruitment of a convenience sample of dieticians, and a modest sample size for interviews, all of which limit the transferability of findings. In addition, we experienced a lack of diversity in clinical and sociodemographic factors for surveys and interviews. We selected a parallel convergent approach for data collection and analysis and followed with an integration approach (merging) to synthesize our mixed methods data; while a sequential approach may have allowed more iterative app development and testing, this approach was selected to facilitate rapid technology development.

In summary, this study identified the optimal content for a mobile support app for caregivers of people with HNC and supported the acceptability of implementing this intervention at the end of treatment. Future steps include evaluating the implementation of the HEART app and its impact on survivor and caregiver outcomes. It will be important for a future study to rigorously test the HEART app in a prospective clinical trial.