Objectives

Conventional face-to-face nutrition counseling has played a crucial role in promoting healthy habits. However, the emergence of digital health technologies has introduced mobile app-based nutrition counseling as an effective alternative. This research aims to develop and evaluate the usability and effectiveness of the FIT4PEDON mobile nutrition counseling application in promoting healthy dietary behaviors and lifestyle modifications among childhood cancer survivors (CCS).

Methods

This study employed a mixed-methods approach, incorporating both survey and qualitative and quantitative analyses. A total of 33 health care professional experts participated. The reliability of the questionnaire was assessed using the Kuder-Richardson method, and its content validity was confirmed through expert evaluation. Usability testing was conducted with a validated questionnaire.

Results

The development process resulted in two applications: an Android mobile application and an admin web application. The findings indicated that a significant proportion of experts endorsed the app for dietary management. Statistical analysis showed significant differences between “yes” and “no” responses. However, no significant differences were found when comparing responses across different sex or age groups.

Conclusions

The FIT4PEDON application shows promise in supporting CCS to adopt healthier lifestyles. Nevertheless, the study underscores the necessity for further research, particularly focusing on specific age groups of experts with relevant experience, to achieve more conclusive results. Leveraging technology through mobile apps has the potential to improve the quality of survivorship care and foster sustained engagement in long-term care for pediatric cancer survivors.

Keywords: Digital Health, Cancer Survivors, Delivery of Health Care, Mobile Applications, Long-Term Care

I. Introduction

Childhood cancer encompasses a wide range of malignancies, each characterized by unique patterns of incidence, etiology, treatment strategies, and supportive care. Pediatric oncology has seen significant advancements, leading to substantial improvements in cancer treatments. As a result, more than 85% of pediatric cancer patients now become long-term survivors [1]. Recent studies indicate that there are over 500,000 pediatric cancer survivors in North America alone [2]. Over the last 60 years, advancements in treatment and patient care have enhanced outcomes for children aged 0–14 years diagnosed with cancer. According to a World Health Organization report, the 5-year overall survival rate for these pediatric patients has dramatically increased from 30% in the 1960s to over 80% in recent years [3]. Both children undergoing cancer treatment and childhood cancer survivors (CCS) often report poor dietary choices and unhealthy habits, which may increase their risk of long-term health issues [4]. Dietary patterns are crucial in both the prevention and development of chronic diseases, including cancer, and their impact extends beyond just obesity. For CCS, nutrition and diet are especially critical as they are modifiable factors that can help prevent or delay the onset of chronic diseases [5].

With the significant increase in smartphone usage, mobile applications (apps) have become powerful tools for supporting and improving health-related behaviors. Research indicates that dietary mobile apps are effective self-monitoring tools that have positive effects on measured nutritional outcomes, particularly in managing chronic diseases [6,7].

Moreover, parents and guardians of CCS are crucial in promoting healthy eating habits for their children. They play a key role in the survivorship journey, offering essential support that improves the quality of life for CCS. Optimizing nutritional care models that are most acceptable to patients and their families is vital [8,9]. Therefore, this study aims to develop and evaluate the usability and effectiveness of an innovative Android mobile nutrition counseling application designed to promote lifestyle modifications in CCS.

II. Methods

The study employed a mixed-methods research design across various phases to develop and evaluate the FIT4PEDON Android mobile application, a nutrition counseling tool for childhood cancer survivors (Figure 1).

The research design utilized both qualitative and quantitative methods. This pilot study sought feedback from 33 healthcare professionals regarding the features and functionality of the FIT4PEDON mobile app. The sample size was established based on reference articles pertinent to usability trials. The study was conducted over a period of 3 months, from May to July 2020.

Development of the Prototype Application

Development of the Prototype Application

1) Phase I: Literature review, research design and formulation of the research questions

1) Phase I: Literature review, research design and formulation of the research questions

This study conducted an integrative literature review (IR), adhering to the guidelines outlined in the Guide to Conducting an IR 2020. Electronic searches were conducted across several reputable databases, including PubMed, Scopus, Science Direct, and Web of Science, as well as Google Scholar. The searches utilized the following keywords: Mobile app development, Usability evaluation methods, Mobile app usability testing, Childhood cancer survivor, and Mobile app-based nutritional counseling [11,12]. These keywords were strategically combined using “and” or “or” to facilitate Boolean searches. The inclusion criteria for the study were articles on mobile app development and/or nutrition counseling, as well as usability studies on mobile apps, published in English between January 2010 and January 2020. The exclusion criteria were non-empirical studies, systematic reviews, meta-analyses, and studies focusing on web-based nutritional counseling.

Coding in qualitative research involves analyzing texts to identify themes and extract meaning from the data [13–15]. This study employed the inductive coding method, beginning with open coding to identify initial codes, followed by axial coding to refine these themes, and concluding with selective coding to develop a meaningful theory. Manual methods were used for data analysis, including coding on hard-copy printouts in small-scale studies to enhance control and ownership [14,16]. Peer debriefing, supported by research experts, was also implemented. This process involves discussions with individuals outside the research team, which adds trustworthiness and rigor. Peer debriefing helps refine the research process, ensures credibility, and improves the various phases of the study. The insights gained through this process helped address biases, clarify ideas, and increase the overall trustworthiness and rigor of the research [17,18].

• - Research Question 1: Is the mobile application accepted by study participants as a means of promoting and sustaining healthy dietary behaviors and lifestyle modifications among CCS?

• - Research Question 2: How reliably does the FIT4PEDON mobile application support and promote healthy dietary behaviors and lifestyle modifications among CCS?

2) Phase II: Design and development of the mobile application and web backend

2) Phase II: Design and development of the mobile application and web backend

The recommended system requirements included Linux as the operating system, ideally equipped with PHP hosting capabilities. MySQL was selected as the database for its reliability and performance. Additionally, Apache, which is preferably used with Linux and PHP support, was recommended as the web server. The development process was streamlined using HTML5, CSS3, PHP, MySQL, and frameworks such as CodeIgniter and Laravel. Bootstrap was employed for its responsive design capabilities, ensuring the application’s adaptability across various devices. The versatile and robust Java language was chosen for coding, while Android Studio served as the primary development tool, providing a user-friendly environment for creating, testing, and optimizing the Android application. The application design was translated into functional web-based components using HTML, CSS, PHP, and MySQL. Finally, an intuitive and visually appealing user interface was developed using HTML, CSS, and Bootstrap to meet the needs of the target users.

3) Phase III: Prototype testing

3) Phase III: Prototype testing

The FIT4PEDON mobile app prototype underwent rigorous testing to assess its functionality, usability, bugs, and performance. This study emphasized meticulous data handling to enhance transparency and credibility. Testing involved a selected group of ten users, specifically parents or legal guardians of children with CSS. During these sessions, users were encouraged to provide feedback, and their comments, suggestions, and observations were carefully recorded to capture valuable insights. Bugs were promptly addressed, and feedback was used to refine the prototype.

Questionnaires were reviewed and converted into a Google Form, ensuring both accuracy and usability. This process included distributing the questionnaires, collecting responses, and conducting statistical analysis. Demographic data and reliability assessments were thoroughly verified to ensure both accuracy and credibility. The trustworthiness of the mobile app was enhanced through a comprehensive research design, expert reviews, and close collaboration between the development team and researchers, aimed at improving usability and effectiveness.

Usability Testing of the Prototype

Usability Testing of the Prototype

1) Phase IV: Questionnaire design and development—validation process overview

1) Phase IV: Questionnaire design and development—validation process overview

The quantitative phase involves developing the FIT4PEDON Android app. A dichotomous questionnaire consisting of 25 closed-ended questions was created and transformed into a Google Form to facilitate efficient remote data collection. This digital approach proved particularly beneficial during the COVID-19 pandemic by enhancing accessibility for subsequent phases of the study. The inclusion criteria encompassed healthcare professionals with expertise in pediatric oncology, general pediatrics, and pediatric education, as well as those holding a Bachelor of Medicine, Bachelor of Surgery (MBBS) degree, and post-graduate doctors specializing in pediatrics. Participants should also be experienced in using mobile app-based nutrition counseling. The exclusion criteria were set for individuals who lack a background in healthcare, pediatric oncology, or nutrition, as well as those who are unwilling to actively participate in the study or are not familiar with mobile app-based nutrition counseling. The study utilized purposive sampling, a non-probability sampling technique, to select participants. Recruitment was conducted through social media platforms including LinkedIn, Instagram, and Facebook.

The institutional ethical committee of Sri Ramachandra Institute of Higher Education and Research approved this study (REF: IEC/19/AUG/153/59). The study adhered to the ethical standards and guidelines set by the institution. Data were computed and securely stored. The questionnaire comprised 25 dichotomous closed-end questions covering effectiveness, usability, satisfaction, and acceptability, utilizing a dichotomous format to facilitate efficient data collection. To ensure the reliability of the questionnaire, the Kuder-Richardson method (KR20) was employed to assess its internal consistency. Participants were asked to respond to each question with options such as “strongly agree”/“agree” or “yes” at one end, and “strongly disagree”/“disagree” or “no” at the other. This scoring method effectively distinguished between the different response categories, aiding in the reliability assessment. The questionnaire was converted into a Google Form as shown in Figure 2. To enhance participants’ understanding of the mobile app’s user interface and features, a screen-recorded video demonstration was included in the Google Form, providing a comprehensive visual guide to the application’s functionalities. The validation process began with a thorough review of the questionnaire by experts to ensure content validity. The experts verified that the questions were clear, relevant, and comprehensive, aligning with the research objectives. Internal consistency and reliability were further assessed using the Kuder-Richardson method. Additionally, the questionnaire’s content validity was evaluated by computing the content validity index (CVI) with reference to a relevant article [19]. The CVI value of 0.85 indicated a high level of content validity, confirming the robustness of the validation process and preparing the questionnaire for the next phase.

2) Phase V: Usability evaluation of the mobile application and data collection

2) Phase V: Usability evaluation of the mobile application and data collection

The usability test of the FIT4PEDON mobile app employed a validated questionnaire. During the evaluation, a validation sheet questionnaire was distributed to 33 health professionals who are experts in their fields. These experts were asked to complete the questionnaire, providing valuable feedback on the application’s user interface, features, and overall usability. The goal of the evaluation process was to identify any usability issues, areas for improvement, and suggestions for enhancing the user experience of the application. The feedback collected through the validation sheet questionnaire was instrumental in refining the mobile app, making it more user-friendly and effective. It is important to note that the usability test focused specifically on the “pre-FIT4PEDON” version of the app. At the conclusion of this research, we plan to conduct a usability test on the final version of the app soon, with the results to be detailed in an upcoming study.

Final Version of the Application

Final Version of the Application

After the final version of the application was developed, we incorporated necessary improvements to enhance its user-friendliness and effectiveness. This was followed by a successful usability test, culminating in the completion of the mobile app. Subsequently, the final APK file of the FIT4PEDON mobile app was uploaded to the Google Play Store, along with its logo as shown in Figure 3. This made it readily accessible to its intended users—parents or legal guardians of CCS. Users can now download and install the FIT4PEDON mobile app on their Android devices, empowering them to support healthy eating and lifestyle improvements for CCS.

Statistical Analysis

Statistical Analysis

The participants’ responses underwent statistical analysis to evaluate their opinions and preferences concerning the usability and effectiveness of the mobile app (p < 0.05 is considered a significant level). The t-test and chi-square test were used to determine if there were significant associations between the categories of healthcare professionals and their responses to the questionnaire [20]. For small sample sizes, where expected cell frequencies were less than 5 in 2 × 2 tables, Fisher exact test was employed in conjunction with the chi-square test to ensure accuracy. Eight strategic questions were selected from a total of 25 to focus on critical aspects of the app’s functionality and user experience, including preferences, past experiences, and perceived effectiveness.

III. Results

Development of a Client-Centric Android App

Development of a Client-Centric Android App

The first interface, “Get Started,” allowed users to familiarize themselves with the app’s features and functionalities. The main menu options, such as demographic data, anthropometry data, and diet history. The “Food Monitoring” section allowed users to track their daily food intake, as shown in (Figure 4). “One Step Forward” featured four exercise videos: warm-up, warm-down, stretching, and floor exercises. “Nutri Guide” provided users with nutritional educational pamphlets, offering valuable information and resources. The application was intended for individuals aged 18 and older. For children under 18, parents or legal guardians were authorized to use the application on their behalf.

Web Backend for Streamlined Administration

Web Backend for Streamlined Administration

To closely monitor and analyze the data collected through the application, as shown in Figure 5, the investigator accessed the data from the web backend to evaluate participants’ dietary behaviors. Investigators could also send personalized notifications, timely reminders, and encouragement to individuals.

Demographic Data of Experts

Demographic Data of Experts

The study participants represented a diverse age group, with the majority aged between 24 and 40 years. Most participants were female, accounting for 69.6% of the sample. Regarding qualifications, a significant majority, 75.5%, were working professionals, and graduates made up 24.2% of the participants. These demographic characteristics illustrate the diversity of the participant pool (Table 1).

In Supplementary Table S1, the KR20 reliability test result of 0.73 was deemed acceptable according to Equation (1):

(1)

KR20=K÷K-1 [1-∑pq÷s2].

Data Analysis

Data Analysis

The participants’ demographic data were analyzed using percentages and frequencies. The KR20 reliability assessment and content validity were calculated with Microsoft Excel 2019 (Microsoft, Redmond, WA, USA), and further analyzed using SPSS software version 26 (IBM, Armonk, NY, USA) [21,22]. A significant majority of experts (94%) expressed a preference for a mobile app to manage their diet. In contrast, slightly more than half of the participants (52%) reported using a mobile app to improve their diet, while a marginally smaller percentage (48%) did not use one. The analysis showed no statistically significant differences in the perceptions of tailored dietary mobile apps across various age groups and sex. Tables 2,–4 present detailed expert opinions on mobile app usability, age-based preferences, and sex-based responses, respectively.

As shown in Table 3, the highest percentage of participants who preferred the app was in the <30 years age group (36.4%), followed by the 31 to 40 years age group (42.4%). These preferences did not show a significant difference, as indicated by a p-value of 0.822. The percentage of participants who used the app for dietary improvement was also higher in the <30 years age group (27.3%) compared to the other two age groups. However, this difference was not statistically significant, with a p-value of 0.260. In the 31 to 40-year-old age group, a higher percentage of participants (42.4%) found the plans effective; however, this difference was also not statistically significant, with a p-value of 0.499. Additionally, the lack of significant results may be influenced by the nature of the questions asked. Participants’ subjective responses to questions about preferences, perceptions, and app usability can vary and sometimes lead to statistically significant differences, especially in a relatively small sample, as seen in Questions 4 to 8, which explored various aspects of the app’s usability and benefits. It is important to note that the participants’ responses did not exhibit statistically significant differences across age groups, as all associated p-values were greater than 0.05.

As presented in Table 4, the results indicated that among female participants, 88.3% preferred the mobile app for dietary management (45.5% of the total participants were female, and 6.1% did not prefer the app). Among male participants, preference for the app was unanimous at 100% (48.5% of the total participants were male). This demonstrates relatively similar preferences between the males and females, which were not statistically significant (p = 0.157). These findings collectively suggest that sex does not play a significant role in shaping preferences and perceptions related to the usability of the mobile app. Males and females generally responded positively to the app, indicating its potential effectiveness in supporting dietary management for CCS, regardless of sex. Regarding the use of the app for dietary improvement, 64.6% of females (33.2% out of the total 51.5% female participants) and 37.6% of males (18.2% out of the total 48.5% male participants) reported positive responses. The difference between males and females was not statistically significant (p = 0.118). Similarly, regarding the effectiveness of tailor-made dietary plans for weight management, 76.5% of females (39.4% of the total female participants) and 93.8% of males (45.5% of the total male participants) found the plans effective. Again, the difference in responses did not reach statistical significance (p = 0.245). Additionally, 51.5% of female participants and 87.4% of males expressed a willingness to recommend the app to other cancer survivors during follow-up, with no significant sex difference observed (p = 0.133). Questions 5 to 7 also showed no significant differences in responses between the males and females. The implementation of tailor-made diet plans via a mobile app for children who are cancer survivors appears to be effective, with results showing statistical significance (p = 0.038). Overall, the study indicated generally positive responses from males and females towards the app, suggesting its potential effectiveness in supporting dietary management for cancer survivorship.

IV. Discussion

The results of this study indicated that all positive feedback concerning the mobile app was statistically significant, as shown in Table 2. This feedback included high levels of user satisfaction, effectiveness, and confidence in the app’s capacity to fulfill needs and offer valuable features.

Other studies have concluded that digital health enhances pediatric diet quality, especially since 97% of Australian households with children under 15 have internet access [23]. Researchers have observed that text message interventions positively affect child health behaviors associated with childhood obesity [24]. Additionally, telehealth services overcome international barriers and enhance access to quality healthcare. Continued research and collaboration are crucial for optimizing digital health interventions and broadening their impact on health outcomes in pediatric populations [25].

Larger sample sizes could increase the statistical power, helping to detect significant differences. Additionally, the uniformity in preferences and responses across different age groups might indicate that the app’s usability and benefits are perceived similarly by participants from various age brackets. This uniformity can be viewed as a positive result, suggesting widespread acceptance and potential applicability of the app across diverse age demographics.

The study highlights the potential of digital health interventions to promote healthier eating habits and enhance nutrition awareness. It analyzed age-related trends in participants’ preferences for the mobile app’s usability, revealing preferences across different age groups, although these differences were not statistically significant. The lack of age-related distinctions suggests a broad acceptance of the mobile app among participants of various ages. Additionally, the study explored sex-based differences in app preferences and perceptions. The findings indicate that sex did not significantly influence participants’ attitudes toward the app, with males and females generally providing positive feedback. However, it is crucial to acknowledge that other unexplored factors, such as prior exposure to technology and personal health goals, might affect individual preferences. These factors should be considered in future research.

In summary, this study is unique as it represents the first exploration of research findings from mobile app-based nutrition counseling. Future research and collaboration are crucial for optimizing digital health interventions and expanding their reach to improve health outcomes in pediatric populations through the use of advanced machine learning and deep learning methods.

Notes

Conflict of Interest

No potential conflict of interest relevant to this article was reported.

Supplementary Materials

Supplementary materials can be found via https://doi.org/10.4258/hir.2025.31.1.37.

hir-2025-31-1-37-Supplementary-Table-S1.pdf

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