Development of a Website for E-Health Use for Children with Chronic Suppurative Lung Diseases: A Delphi Expert Consensus Study

Abstract

This study aimed to develop a website providing physiotherapy, exercise, and disease knowledge information as a digital tool for use with children with chronic suppurative lung diseases (CSLDs). Data were analyzed using a mixed qualitative and quantitative approach. Initially, a comprehensive list of the website’s content and functions was developed through a Focus Group study with healthcare professionals (HCPs) and parents. Afterward, two rounds of an online Delphi survey were conducted with a group of expert HCPs (pediatricians and physiotherapists) who were recruited based on their expertise in the field of pediatric physiotherapy. The Focus Groups established 10 main themes. Two rounds of Delphi questionnaires established the important items of a website, based on expert consensus from HCPs. A Delphi survey containing 36 outcomes was completed by participants from Greece. The findings support the integration of multidisciplinary and user-centered approaches in the design of a pediatric website. This website is expected to enhance disease self-management, improve treatment adherence, and support families in daily care.

1. Introduction

Chronic suppurative lung disease (CSLD) is a clinical term for conditions that, in children, are characterized by a persistent or recurrent wet cough, endobronchial infection, and neutrophilic airway inflammation, without radiographic evidence of bronchiectasis on high-resolution CT (HRCT) [1,2]. Conditions under the CSLD umbrella include protracted bacterial bronchitis (PBB), non-cystic fibrosis bronchiectasis (NCFB), primary ciliary dyskinesia (PCD), and immunodeficiency-related lung disease [1,2,3].

CSLD is increasingly recognized as a major cause of pediatric respiratory morbidity worldwide. It remains prevalent in low and middle income countries, especially among socially disadvantaged and indigenous children, highlighting the need for global action and equitable care strategies [3]. Timely diagnosis and treatment are essential, as CSLDs may be reversible, while delayed management increases the risk of progression to irreversible bronchiectasis [4]. Management includes antibiotics, airway clearance, exercise, and regular monitoring [5]. Optimal care can improve and even normalize lung function in children; however, access to multidisciplinary care, especially paediatric physiotherapy, is limited. Personalized, high-quality care is key to preventing decline and improving quality of life [6].

Several studies have demonstrated the potential of digital health sources (DHSs) to improve clinical outcomes and disease management in children with CSLDs. The use of mobile applications, e-Health exercise programs, serious games, and telehealth tools has been associated with improved treatment adherence, better symptom monitoring, enhanced functional capacity, and increased health knowledge [7]. While many interventions show promise, challenges remain regarding accessibility, cultural relevance, and the need for high-quality evidence to support widespread implementation [8,9,10,11]. Healthcare professionals (HCPs) and parents of children with CSLDs may play a central role in the development and implementation of digital health solutions, as their perspectives on barriers and enablers are crucial for their successful adoption. Considering the vast technological advancements and recognizing the importance of digital health in shaping the future of medical advances is key for the optimization of current and new DHSs [12].

It is essential to acknowledge that a significant gap remains in educational and informational materials specifically designed for children with CSLDs. Families and pediatric patients often have limited access to structured, evidence-based resources related to the disease itself, as well as its pharmacological and non-pharmacological management, including airway clearance techniques, physical activity, and nutrition. The aim of this study was to develop a website that provides reliable, accessible, and practical information on medication, physiotherapy, nutrition, exercise, and disease education for children with CSLDs and their caregivers.

2. Materials and Methods

2.1. Study Design

This research was conducted in two sequential stages: Focus Group discussions, followed by two rounds of Delphi consensus questionnaires. The Committee for Research Ethics of the Physiotherapy Department of the University of Thessaly approved all the study procedures (protocol number: 14892/12-07-24). Prior to commencing the online survey, participants were provided with an information sheet and consent form. Consent was confirmed via a checkbox before participation.

2.2. Research Questions

The research questions were as follows: (a) What are the content and functions of a website for use in children with CSLDs? (b) Do you believe that the following items related to content and functions could be incorporated in a website for children with CSLDs?

2.3. Scope

This study aimed to develop a website to inform users regarding disease symptomatology management. It targets children aged 6–12 years, whose main symptoms are a productive cough and abnormal sputum.

2.4. Stage 1: Focus Group

Focus Groups are a cost-effective, quick, and more efficient alternative to one-on-one interviews for gathering data from multiple participants [13].

2.4.1. Participants

Purposive sampling was used. Two groups were invited to participate in this study, Group A (pediatricians and physiotherapists) and Group B (parents). Consequently, Group A consisted of professionals who (a) had more than 5 years of clinical experience, (b) were specialized in pediatrics, and (c) were working with children with CSLDs. Members of Group B were (a) parents of a child diagnosed with CSLD, and (b) parents who had a child receiving regular treatment at a pediatric clinic in a public hospital or a private clinic in Greece.

Recruitment was through an email invitation sent to public hospitals and private clinics across Greece, aiming to include HCPs actively involved in managing children with CSLDs. Parents were approached through the same clinical settings where the participating HCPs practiced; in most cases, they were first informed about the study directly by their child’s clinician and were later contacted by the research team.

2.4.2. Procedure

Two online Focus Groups were conducted via Microsoft Teams, one with HCPs and one with parents of children with CSLD. Each session lasted approximately 90 min and was moderated by a professor experienced in qualitative research, assisted by two facilitators. The discussions followed a semi-structured topic guide (Supplementary Table S1), which was previously pilot-tested and refined. Sessions were recorded using OBS Studio and later transcribed verbatim. Participants were recruited through email invitations and verbal referrals, provided informed consent, and directly completed the demographic data collection form.

2.4.3. Data Analysis

A thematic analysis was conducted for the current qualitative study. A verbatim transcription was carried out followed by thematic analysis of the discussions. Initiating theme development included a thorough review of all codes to identify patterns, relationships, and interconnections, which subsequently informed the formulation of preliminary thematic categories.

2.5. Stage 2: Delphi Survey

A two-round Delphi survey was employed to reach consensus on the listed items, facilitating agreement on those considered most important [14]. This approach is extensively applied within medical and nursing fields and is recommended when aiming to capture nationwide perspectives and establish priority areas [15].

2.5.1. Sample and Recruitment

One group was invited to participate: HCPs (pediatricians and physiotherapists) with at least one published work related to CSLDs in the past three years, those who delivered keynote or invited presentations at major meetings focused on pediatric pulmonology or respiratory physiotherapy, and those with postgraduate certification in CSLDs.

The Focus Group of HCPs was asked to nominate a list of 50 participants from their professional networks, including pediatricians and physiotherapists, who had adequate scientific training and clinical experience to take part in the Delphi process and possibly expand the sample size. Selecting participants was considered crucial for ensuring the validity of the study’s conclusions. Therefore, purposive sampling was used to target individuals with proven expertise and practical experience, relevant backgrounds related to the study topic, the ability to provide valuable insights, and a willingness to revise their initial or previous judgments to achieve the highest possible level of consensus.

2.5.2. Formulation of the Survey Items

A steering committee was formed to oversee the Delphi process, including preparing the list of items and assessment findings for Round 1, evaluating the outcomes of Round 1, and reviewing responses to Round 2. The 36 items of Round 1 were derived directly from the thematic analysis of the Focus Group discussions (Supplementary Tables S2a,b and S3a,b). Each main theme and its subthemes were converted into specific, concise questionnaire items using wording that closely reflected the participants’ original phrasing. Two researchers (VS and AM) independently coded the transcripts and proposed candidate items. Discrepancies were resolved through discussion with a third senior researcher (EKο) to ensure reliability and content validity. A detailed mapping of Focus Group themes, representative quotes, and corresponding Delphi items is presented in Supplementary Table S4. The committee consisted of three members with expertise in chronic pediatric lung diseases: one Professor of Pediatric Pulmonology and two Professors of Physiotherapy. An online survey was developed, and pilot tested to ensure clarity, feasibility, and technical performance before data collection.

2.5.3. Delphi Survey: Round One (R1)

A total of 49 participants evaluated each outcome’s significance based on their personal experience and opinions. A three-point Likert scale was used to score items according to their importance [16]. A score of 1 signified an outcome of limited importance, 2 important but not critical, and 3 critical. An open-ended section allowed respondents to propose additional outcomes, which, if absent from the initial list, were incorporated into the second-round survey. Data collection took place between 15 September and 15 October 2024, with weekly email reminders issued to promote participation.

2.5.4. Delphi Survey: Round Two (R2)

Participants who completed R1 were sent invitations to complete R2, which was open from 1 November 2024 to 2 December 2024. Items that reached a consensus level between 50 and 80% were carried forward to R2, along with new items proposed through the open-ended question in R1. Participants were asked to consider the previous group ratings and re-evaluate each item using the same Likert scale. Weekly email reminders were sent to encourage participation.

2.5.5. Data Analysis

Data analyses were performed and presented separately for pediatricians and physiotherapists. Participant rating percentages for each item from both the first and second rounds were used to determine the level of consensus, based on predefined criteria. Consensus was defined as agreement equal to or greater than 80%. Near-consensus was defined as agreement between 50 and 80%, while disagreement (or lack of consensus) was defined as less than 50% agreement for any of the possible responses. Consensus thresholds were pre-specified based on methodological guidance for health-related Delphi studies [17]. Although the COMET Handbook and other studies frequently define consensus as at least 70% of participants rating an outcome as critical and no more than 15% rating it as unimportant, there is no universally accepted standard for establishing consensus in Delphi surveys [18,19]. Thresholds between 70% and 80% have been used in previous studies [20]. We opted for the 80% cut-off to ensure more stringent agreement among participants, given the need for high confidence in prioritizing outcomes in this study.

For the descriptive analysis of the data from both the first and second round questionnaires, parametric statistical testing was performed. The Kolmogorov–Smirnov test was used to assess the normality of the distribution. All continuous variables (e.g., demographic characteristics) were expressed as mean ± standard deviation and median (interquartile ranges). Categorical variables (e.g., level of agreement, response rate) were presented as numbers (n) and percentages (%). Based on the normal distribution, the independent t-test, Mann–Whitney U test, and Fisher’s exact test were used to explore differences between demographic characteristics. To enhance the clarity of data presentation, percentages and decimal points were rounded where appropriate. Statistical analysis was conducted using SPSS for Mac, Version 29.0 (SPSS Inc., Chicago, IL, USA).

3. Results

3.1. Focus Group Participants’ Characteristics

A total of thirteen individuals participated in the study: seven HCPs (median age 51 years; interquartile range (IQR): 36–59) and six parents (median age 43 years; IQR: 39–48). Five out of the seven HCPs (71.42%) worked at a public hospital, and four of them (57.14%) held an MSc in pediatrics. All parents were female. Participants’ demographic characteristics are presented in

Table 1. Demographic data collection for participants of Focus Group.

Professionals’ Characteristics		Parents’ Characteristics
ID/Professions	Work Experience	ID/Parents	Diagnosis	Child Age
HCP1/MD	>31	P1	Primary ciliary dyskinesia	6–12
HCP2/MD	>31	P2	Bronchiectasis	6–12
HCP3/PT	21–30	P3	Bronchiectasis	6–12
HCP4/PT	11–20	P4	Cystic Fibrosis	6–12
HCP5/PT	11–20	P5	Cystic Fibrosis	12–18
HCP6/MD	5–10	P6	Bronchiectasis	12–18
HCP7/PT	5–10

ID: identification; HCP: healthcare professional; MD: medical doctor; PT: physical therapist.

.

3.2. Delphi Participants’ Characteristics

Of 50 participants, 49 (98%) responded in R1: 12 (24.5%) pediatricians and 37 (75.5%) physiotherapists. In total, 38 (77.6%) respondents were female, while 11 (22.4%) were male. Detailed demographics of participants for R1 are displayed in

Table 2. Demographic data collection for participants of Round 1 (n = 49).

Characteristics
	Pediatrician	Physiotherapist	p-Value
Number (n)	12 (24.5%)	37 (75.5%)	<0.001 *
Age (years)	37.5 (35.5–58.25)	42.76 ± 9.15	0.598
Work experience (years)	12 (10–34.5)	18.59 ± 8.65	0.600
Gender (male/female)	1/11	10/27	0.252
Level of education
MSc	8 (66.7%)	26 (70.3%)
PhD	4 (33.3%)	7 (18.9%)
Employer
Private clinic	3 (25%)	26 (70.3%)
Public hospital	9 (75%)	11 (29.7%)
MSc in pediatrics	9 (75%)	13 (35%)
Publications related to pediatrics	9 (75%)	10 (27%)

Data are presented as mean ± SD, median (IQR: Q1–Q3), numbers (n), and % percentage; MSc: masters; PhD: doctor of philosophy; * Statistically significant differences (p < 0.001).

. Given that only one participant did not respond in R1, it was not possible to assess the systematic differences between responders and non-responders.

In R2, 44 of 50 participants (88%) responded; 10 (22.7%) pediatricians and 34 (77.3%) physiotherapists. Detailed demographics of participants for R2 are displayed in

Table 3. Demographic data collection for participants of Round 2 (n = 44).

Characteristics
	Pediatrician	Physiotherapist	p-Value
Number (n)	10 (22.7%)	34 (77.3%)	<0.001 *
Age (years)	46.2 ± 12.53	42.97 ± 9.34	0.464
Work experience (years)	13 (9.5–35)	18.77 ± 8.9	0.707
Gender (male/female)	1/9	10/24	0.408
Level of education
MSc	8 (80%)	24 (70.6%)
PhD	2 (20%)	6 (17.6%)
Employer
Private clinic	2 (20%)	24 (70.6%)
Public hospital	8 (80%)	10 (29.4%)
MSc in pediatrics	8 (80%)	11 (32.4%)
Publications related to pediatrics	8 (80%)	8 (23.5%)

Data are presented as mean ± SD, median (IQR: Q1–Q3), numbers (n), and % percentage; MSc: masters; PhD: doctor of philosophy; * Statistically significant differences (p < 0.001).

.

3.3. Focus Group’s Results

3.3.1. Content

Participants in both Focus Groups emphasized the importance of developing a child-centered website tailored to the daily management of CSLDs. Five main themes emerged: information provision, aesthetics, gamification, evidence, and co-design (Supplementary Tables S2a and S3a). Key similarities and differences were observed between HCPs and parents, with both groups focusing on the accessibility and engagement of the digital platform.

Information

Clear, reliable, and accessible medical information was highlighted by all HCPs and five parents. HCPs stressed the inclusion of evidence-based content about the disease and its treatments:

“The website should include clear explanations of the disease—what chronic suppurative lung disease is and how it affects children.”

(HCP2)

Parents, in turn, emphasized the challenge of recalling instructions after medical visits and the desire for medically approved, trustworthy resources:

“Sometimes we leave the hospital with so many instructions that it’s hard to remember—if it was written on the website, it would help a lot.”

(P2)

“We often google things, but it’s hard to know what to trust. I’d prefer having reliable, doctor-approved information in one place.”

(P6)

Key areas of interest for both groups included physiotherapy techniques (mentioned by six HCPs and four parents), nutritional guidance (five HCPs, three parents), and exercise recommendations tailored to the child’s condition.

Aesthetics

Aesthetic appeal was considered essential for child engagement, mentioned by five HCPs and all parents. Parents particularly stressed the need for colorful, joyful, and age-appropriate designs:

“It should be something colorful, something cheerful that catches their attention.”

(P2)

“… in our case, for children around the age of six, it should be something colorful, something joyful that captures their interest.”

(P4)

HCPs echoed this view, adding the need for content to remain dynamic and avoid monotony:

“It should be entertaining and a little different each time—the same ideas but varied presentations.”

(HCP1)

Simplicity and ease of use were also emphasized by four HCPs and five parents.

Gamification

Gamification was viewed as a core engagement tool, mentioned by four HCPs and five parents. HCPs proposed the integration of serious games and interactive features such as blowing games connected to remote monitoring:

“Games that involve blowing, the measurements of which will be sent directly to the corresponding center of the website.”

(HCP6)

Parents highlighted the idea of a digital “imaginary friend” or hero to accompany children through their therapy journey:

“A hero could be created who grows with them and experiences the therapy alongside them.”

(P5)

“Well, I believe that a digital friend within the tool would be very helpful. An electronic friend that they could see on their phone through virtual reality.”

(P4)

Three-dimensional animation was suggested by three HCPs and three parents as a means to sustain engagement during therapy.

Evidence

All HCPs emphasized the importance of ensuring that all content is based on clinical evidence and supervised by qualified professionals:

“All information should be drawn from evidence-based research and literature.”

(HCP4)

“The final advice should come from the specialist paediatric respiratory physiotherapist and the doctor.”

(HCP6)

Co-Design

Involving end users in the design process was supported by five HCPs:

“Children should be part of the design process—they’re the end users, and their input is crucial for usability.”

(HCP2)

“Parents are aware of the daily challenges better than anyone.”

(HCP6)

3.3.2. Functions

Five main functional themes emerged: technical support, training, remote monitoring, accessibility, and multilingual access (Supplementary Tables S2b and S3b). The priorities of HCPs focused more on clinical utility and customizability, while parents highlighted communication, support, and daily usability.

Technical Support

Both groups emphasized the importance of system-guided reminders and sound notifications to enhance adherence, with seven HCPs and five parents mentioning this feature:

“Some kind of electronic reminders for children, telling them that it’s time to take their medication, it’s time for physiotherapy.”

(HCP1)

“A daily reminder or whenever necessary, in a pleasant way that doesn’t feel burdensome.”

(P1)

Additionally, four parents requested features such as phone support, email, and chat systems, especially for real-time emotional or technical concerns.

Training

Training was seen as crucial by five HCPs and four parents. HCPs suggested structured in-clinic instruction and asynchronous resources:

“Training is needed … dedicating time and frequent practice. Repetition is the key to learning.”

(HCP1)

Parents appreciated the value of visual aids to support correct implementation at home:

“A video that shows them how to do their respiratory physiotherapy.”

(P5)

Remote Monitoring

Discussed by four HCPs and three parents, remote monitoring features such as electronic spirometers and clinical progress tracking were seen as beneficial:

“I want to monitor the child’s progress—whether there is a steady course, whether things are being done well.”

(P3)

Accessibility

The issue of affordability was mentioned as a potential barrier. Free access to the website was emphasized by all parents and four HCPs:

“If it’s free, they will be able to do it regularly and sustain it.”

(P5)

“Perhaps it could be provided to families through donations.”

(HCP4)

Multilingual

The importance of offering content in different languages to accommodate non-Greek speakers was raised:

“It should definitely be available in multiple languages.”

(HCP6)

3.4. Delphi Results

A total of 36 Delphi survey items were derived directly from the thematic analysis of the Focus Group discussions. Each main theme (e.g., Information) was mapped to specific survey items (e.g., medical, physiotherapy, nutrition, exercise), ensuring continuity between the qualitative and quantitative phases. A detailed mapping of themes, subthemes, representative quotes, and corresponding Delphi items is provided in Supplementary Table S4.

Of the total 36 items included in the first-round questionnaire (

Table 4. Delphi survey Round 1.

Content of a Website
Question 1: Do you believe that the following items related to the content could be incorporated into a website for children with CSLDs?
	Content	Disagree	Neutral	Agree
1.	Information (medical, physiotherapy, nutrition, exercise)	2.1%	2%	95.9%
2.	Simple	2.1%	2%	95.9%
3.	User-friendly	2.1%	2%	95.9%
4.	Interactive (e.g., diary)	2.1%	2%	95.9%
5.	Colorful	2%	10.2%	87.8%
6.	Gamification	2%	2.1%	95.9%
7.	Imaginary friend (avatar)	4.1%	10.2%	85.7%
8.	3D animation	2.1%	16.3%	81.6%
9.	Evidence-based content	2.1%	2%	95.9%
10.	Co-design	2%	10.2%	87.8%
Functions of a Website
Question 2: Do you believe that the following functions could be incorporated into a website for children with CSLDs?
1.	Reminders	2%	8.2%	89.8%
2.	Sound notification	4.1%	10.2%	85.7%
3.	Communication form	2%	18.4%	79.6%
4.	User manual	2%	8.2%	89.8%
5.	Updates	2%	10.2%	87.8%
6.	Modular	2.1%	22.4%	75.5%
7.	Calendar/weekly questionnaire	2%	8.2%	89.8%
8.	Evaluation form	8.2%	14.2%	77.6%
9.	Telephone support	-	8.2%	91.8%
10.	Email	2%	12.3%	85.7%
11.	Chat box	4.1%	16.3%	79.6%
12.	Social media	10.2%	14.3%	75.5%
13.	Diary	6.2%	12.2%	81.6%
14.	Child’s training	-	10.2%	89.8%
15.	Parent’s training	-	6.1%	93.9%
16.	Healthcare professionals’ training	-	6.1%	93.9%
17.	Video	-	2%	98%
18.	Multilingual	-	10.2%	89.8%
19.	Compatible with other devices	-	6.1%	93.9%
20.	Interaction between patients and healthcare professionals	-	4.1%	95.9%
21.	Image uploading	-	4.1%	95.9%
22.	Portable forms (pdf)	-	8.2%	91.8%
23.	Easy navigation	-	4.1%	95.9%
24.	Language adaptability	-	4.1%	95.9%
25.	Strict privacy policies	2%	10.2%	87.8%
26.	Free supply	2.1%	2%	95.9%

CSLDs: chronic suppurative lung diseases

), 31 items reached a consensus level of ≥80% and were considered final; these were not re-evaluated in R2. The remaining five items, which had a consensus level between 50 and 80%, were carried forward to R2 for re-evaluation. Furthermore, in R1, participants suggested three new items through the open-ended responses, which were also included in the R2 questionnaire (

Table 5. Delphi survey Round 2.

Content of a Website
Question 1: Do you believe that the following items related to the content could be incorporated into a website for children with CSLDs?
	Content	Disagree	Neutral	Agree
1.	Electronic leaflets *	8.2%	42.8%	49%
Functions of a Website
Question 2: Do you believe that the following functions could be incorporated into a website for children with CSLDs?
1.	Communication form	4.6%	13.6%	81.8%
2.	Modular	4.1%	12.2%	83.7%
3.	Evaluation form	2.3%	15.9%	81.8%
4.	Chat box	2.3%	13.6%	84.1%
5.	Social media	4.6%	13.6%	81.8%
6.	Live video conference *	16.3%	55.1%	28.6%
7.	Emergency button *	14.2%	42.9%	42.9%
8.	Communication form	4.6%	13.6%	81.8%

CSLDs: chronic suppurative lung diseases. * indicates the items suggested from round 1.

).

In R2 of the questionnaire, eight items were assessed in total. Of these, five reached the consensus threshold (≥80%) and were retained, while three did not achieve consensus: electronic leaflets, live video conference, and emergency button. The lack of consensus for certain innovative digital features suggests that these areas remain uncertain and may warrant further investigation in future research.

4. Discussion

This study contributes to the limited body of literature on digital health sources for improving self-management in children with CSLDs. It is the first to document the development and implementation process of a website designed to provide physiotherapy, exercise, and disease-related information for pediatric CSLDs. Using mixed qualitative and quantitative approaches, it presents a comprehensive overview of the website’s required content and functionalities that are most likely to support a successful adoption of a digital health resource. The website was developed through a human-centered design approach with a focus on children, incorporating the perspectives of HCPs and parents, and addressing the daily management of CSLD. Patient-centered care is essential in the design of digital health technologies, particularly for pediatric populations [21]. The enhanced communication between providers and patients or families can also support the development and implementation of child-centered digital health technologies by encouraging relationship-centered skills in team-based care [22].

4.1. Focus Groups

Initially, the comprehensive list of the website’s content and functions that was developed using a Focus Group study with HCPs and parents established 10 main themes. Similarities and differences were observed between HCPs and parents, with both groups focusing on the accessibility and engagement of the digital platform. HCPs and parents underlined the need for clear, reliable, accessible medical information and evidence-based content. Key areas of interest for both groups included physiotherapy techniques, nutritional guidance, and exercise recommendations tailored to the child’s condition. Evidence-based content and access to accurate information strengthen parents’ and patients’ knowledge about the treatment and increase their self-efficacy [23]. Users of a mobile health platform for self-management of pediatric cystic fibrosis also preferred a mobile application with multiple functions that facilitate access to information, automate disease management, and facilitate communication with the health care team [24].

The aesthetic appeal of the website was considered essential for child engagement. A colorful, joyful, and age-appropriate design is important. Simplicity and ease of use were emphasized by both groups. As reported in other studies regarding digital health, a user-friendly, relevant, and aesthetically pleasing digital environment enhances user satisfaction [25]. Moreover, user-friendly elements, such as incorporating colored line graphs to represent symptom states, are all considered equally important [26]. Gamification was seen as a core component for engagement in remote monitoring. Recent studies have also shown that when the digital environment is presented as a game, it becomes more appealing for systematic and consistent use, such as in practicing respiratory physiotherapy techniques, making gamification a desirable feature [26,27].

Similar approaches have been applied in digital health interventions for other chronic pediatric conditions, offering valuable insights for CSLD website development. For instance, gamified breathing exercise programs in cystic fibrosis have been shown to improve treatment adherence and engagement, particularly when incorporating visual feedback and progressive challenges [10,25]. In asthma management, mobile platforms integrating symptom diaries, medication reminders, and interactive educational modules have demonstrated increased self-management skills and reduced exacerbations [11]. These examples support our emphasis on 3D animations, avatars, and interactive features as strategies to sustain children’s interest and improve adherence to daily physiotherapy. Furthermore, co-design processes used in cystic fibrosis and pediatric obesity interventions have resulted in more acceptable and user-friendly tools, suggesting that the inclusion of children and parents in the design of a CSLD-specific website is likely to enhance its long-term adoption and effectiveness.

Furthermore, HCPs emphasized the importance of ensuring that all content is based on clinical evidence and supervised by qualified professionals. Communication with HCPs, as noted in other studies, also supports the concept of self-management [28]. Co-design is equally important, with participants acknowledging that user involvement in the design process enhances both acceptability and relevance. Research indicates that engaging end users throughout every stage of mHealth development, along with collaboration with healthcare system experts, can lead to applications that sustain user engagement, enhance co-production of services, and ultimately improve self-management and health outcomes [24]. Co-design, in particular, shows strong potential as an effective and empowering strategy for creating interventions that strengthen adolescents’ digital health literacy [29].

Regarding the function of the website, five main themes emerged: technical support, training, remote monitoring, accessibility, and multilingual access. HCPs focused on clinical utility and customizability, while parents highlighted communication, support, and daily usability. Both groups emphasized the importance of system-guided reminders and sound notifications. Additionally, parents requested features such as phone support, email, and chat systems. Moreover, HCPs called for structured training within clinic visits and through asynchronous platforms. Parents appreciated the value of visual aids to support correct implementation at home.

In previous studies, HCPs and parents also agreed that accessibility and technical support are essential in promoting the adoption of digital health technologies. Reminders, telephone supports, user-friendly manuals, audio assistance, etc., improved the ability to handle health situations [21,30]. Additionally, preparation and training time is needed to identify and address technical issues (e.g., internet connection) when they arise, and patients should be introduced to the application’s functionalities in a gradual manner [23]. Allowing them to interact with the app according to their current needs enables a progressive appreciation of its benefits over time, without imposing extra burden [21].

In our study, the potential for integrating remote monitoring was also acknowledged. HCPs referred to tools such as electronic spirometers and tracking forms. Parents echoed a desire for feedback on treatment effectiveness and their children’s health progression. Previous studies have shown that collecting patient-generated health data can lead to more scalable and dynamic platforms, facilitating the use and implementation of mHealth apps [24]. The issue of affordability was mentioned as a potential barrier. Both groups emphasized that the website should be free of charge. Developing affordable and accessible digital health is crucial, as socioeconomic factors significantly affect the use, with users of higher digital literacy and resources benefiting more [31,32]. Finally, the importance of offering content in different languages to accommodate non-Greek speakers was raised, making the multilingual aspect of a website an important factor. Although not a website, the First Nations-specific multilingual Asthma App was found to be easy to use and acceptable for use by HCPs, demonstrating how culturally and linguistically tailored digital tools can effectively support health education in diverse populations [33]. Similarly, a file-based approach was developed to support a multilingual platform, allowing dynamic updates to medication and treatment lists based on clinician input and patient preferences [24].

4.2. Delphi Survey

The Delphi process yielded a high level of agreement among HCPs, with 31 items reaching consensus in R1 and an additional 5 items in R2. These results highlight the shared priorities among pediatricians and physiotherapists regarding the content, design, and functionalities that should be incorporated in a website.

A notable finding was the strong consensus on the inclusion of content related to physiotherapy techniques, exercise, and disease education—core pillars in the management of CSLDs. These outcomes reflect current clinical best practices and underscore the role of digital tools in enhancing continuity of care and self-management. Furthermore, the prioritization of interactive features (such as gamification and training videos), alongside practical elements (like reminders, technical support, and multilingual access), suggests that HCPs value engagement and accessibility as key elements in a successful pediatric website.

The Delphi results also demonstrated the experts’ awareness of caregiver and family needs. The inclusion of items related to parent support, communication tools, and remote monitoring indicates an understanding of the broader psychosocial and logistical challenges families face. These elements align with emerging trends in pediatric digital health interventions, where holistic and family-centered design is increasingly emphasized.

Interestingly, while in some cases the Delphi method is often characterized by variability in consensus levels, our study achieved a relatively high and consistent agreement across two rounds. This may reflect the fact that participants were carefully selected based on expertise and recent academic or clinical contributions in the field. It may also suggest a growing convergence of opinion on the minimum digital standards expected in pediatric care for CSLDs.

Compared to previous core outcome sets or digital design Delphi studies, the present study focused not only on what information should be delivered, but also how it should be accessed and experienced by children and families [34]. Thus, the resulting website model incorporates both clinical and experiential dimensions, marking a shift toward more user-centered and participatory approaches in tool development.

While the majority of items reached strong consensus, certain proposed features did not meet the ≥80% threshold. For example, “Electronic leaflets” and “Live video conference” received lower agreement, possibly reflecting concerns about their added value and the considerable resources required for their implementation and ongoing support. Similarly, the “emergency button” function concerns a technical issue which, although it may be practically useful, is usually not included in websites whose main objective is to create informative material. These lower consensus levels suggest that participants prioritized core self-management and communication functions over supplementary or resource-intensive features.

To ensure that the consensus findings translate into a practical digital health tool, the next phase will involve developing a prototype website incorporating the agreed-upon content and functions. This will be followed by usability testing with children and parents to refine design and features, a pilot implementation in selected clinical settings to assess engagement and feasibility, and finally, efficacy trials to evaluate the impact on treatment adherence, health outcomes, and quality of life. This staged approach will facilitate the creation of an evidence-informed, user-centered platform ready for broader clinical integration.

5. Strengths and Limitations

This study followed a rigorous, two-phase Delphi methodology with high response rates and expert participation from both pediatricians and physiotherapists. The inclusion of a broad set of items reflecting clinical, technical, and user-centered aspects strengthens the relevance and applicability of the findings. The systematic identification and prioritization of features through consensus enhances the potential for real-world implementation and adoption.

However, this effort was specifically targeted at a Greek-speaking population, which may limit the generalizability of the findings. Cultural and contextual factors, along with differences in healthcare infrastructure, funding models, and attitudes toward technology, could influence both the perceived relevance of digital health features and the feasibility of their implementation. In addition, while expert consensus was achieved, validation through end-user testing with children and caregivers is needed to confirm usability and long-term impact. Future research should broaden the sample to include international experts from diverse healthcare systems, enabling comparison of priorities across cultural and organizational contexts. Once a prototype is developed, cross-cultural adaptation and validation studies will be conducted to ensure that the tool is acceptable, relevant, and effective in varied international settings.

The Delphi process was limited to two rounds; although this is a common approach, some researchers recommend a third round to further stabilize consensus, which could have refined the prioritization of items. The study also relied on self-reported ratings of importance without behavioral validation, meaning that stated preferences may not always translate into actual usage or adherence in practice. Finally, physiotherapists represented 75% of respondents, which may have skewed the prioritized content toward physiotherapy-related elements. However, as the scope of this study was disease management rather than exclusively medical management, the strong representation of physiotherapists also reflects their central role in comprehensive care while highlighting the need for more balanced multidisciplinary input in future work.

6. Conclusions

This study identified and prioritized the essential features for a CSLD-focused digital health platform through a rigorous, two-phase Delphi process informed by Focus Group insights from both parents and healthcare professionals. The integration of these complementary perspectives ensured that the proposed design reflects both clinical priorities and family needs. Features receiving the highest consensus included evidence-based content, engaging gamification elements such as 3D animations and avatars, multilingual access, and personalised reminders. By combining user-centred design principles with expert consensus, this work provides a concrete roadmap for developing an accessible, engaging, and clinically relevant tool to support the long-term management of CSLDs in children.