The intervention content development followed a series of steps used in previous mHealth interventions: conceptualization, formative research to inform the development, pre-testing content, pilot study, pragmatic randomized controlled trial, and further qualitative research [
20]. This process is summarized in Figure and discussed in detail below. The methods and results are presented for each step. Ethics approval for a qualitative study (NTX/10/02/006) and an online survey (NTX/10/10/099) were obtained from the Northern X Regional Ethics Committee.
Conceptualization
An expert content advisory group was developed consisting of two cardiologists, a cardiac rehabilitation nurse specialist (CRN), two exercise scientists, a behavioral researcher, an expert in mobile phone delivered interventions [
21,
22] and a M?ori (Indigenous) health researcher. The group met weekly during the 6
month planning stage to determine the overall direction of the intervention, including the content to be included and how it would be delivered. Appropriate behavior change theories [
23] were considered, as well as how to adapt existing American College of Sports Medicine (ACSM) guidelines for exercise-based CR [
24] and behavior change strategies into SMS (160 character text messages) and video format. As a result, important themes for exercise prescription content, behavior change theory and strategies, the purpose of role modeling, and the technology platform to deliver this content were identified prior to formative research.
Study 1: formative research methods
Focus groups and individual telephone interviews were conducted with people with CVD who had attended (attenders), and those who were invited but never attended (non-attenders), a CR program. During this formative stage, we evaluated participants’ beliefs and perceptions of the CR process, perceived barriers, and perceptions of the proposed mHealth CR program of SMS, video messages, and an interactive website.
Attenders were recruited from existing center-based CR programs through established relationships with hospital staff (CRNs). The corresponding author attended the sessions and recruited participants directly. All interested attenders were invited to take part in a focus group, which were conducted the following week after the CR session. In a few cases attenders wanted to take part but could not attend the focus group. These participants were then interviewed over the telephone. In total, 4 focus groups and 5 telephone interviews were conducted in various regions across one city to recruit a more diverse sample.
Non-attenders were recruited by CRNs, who retrospectively reviewed patient records to identify people that had been invited, but did not attend CR. For this group, we conducted one-on-one semi-structured telephone interviews. A key informant focus group was also conducted with three CRNs, who were involved in the recruitment process for this study. Interviews and focus groups were audiotaped and transcribed, and were conducted by the corresponding author.
A general inductive thematic approach was used to identify common themes and meanings from the data [
25]. NVivo9© was used to group items together based on the codes and comments in the margins. Once all data were collected, categories and sub-categories were organized and refined into themes created during analysis. Data were coded and analyzed by the corresponding author and then discussed with the content advisory group.
Formative research results: focus groups and telephone interviews
In total, 41 participants took part in the qualitative research, comprised of 28 attenders, 10 non-attenders, and three CRNs. Demographic characteristics of attenders and non-attenders are summarized in Table .
Qualitative data analysis revealed three distinct themes (see additional file
1: Interview questions and corresponding themes). Differences in responses were found between attenders and non-attenders, but no notable differences were found across sex, age or ethnicity groups. Direct quotes from participants supporting each theme are found in additional file
2: Supporting quotes.
Theme 1: attenders found CR services reassuring and useful
Theme 1 described attenders’ perceptions of CR. Feedback on current CR services was overwhelmingly positive. CR attenders enjoyed the sessions and found them useful, partly due to the interesting and meaningful content, and because it was “easy to understand” (Attender). Attenders discussed the value of being able to ask CRNs and guest speakers (cardiologists, dietitian) questions, as it tailored the content to their specific needs and interests. One of the most highly regarded features of the CR sessions was the group environment. Attenders revealed the support from fellow attenders was comforting and they valued being able to talk to those in a similar situation.
Theme 2: time, transport, and illness were barriers encountered by non-attenders
Theme 2 revealed the majority of non-attenders would have liked to attend CR but encountered significant barriers, such as feeling unwell or illness. Transport difficulties were a significant barrier, including a lack of access to public transport or relying on others to drive them to the sessions, which was not always possible. A few non-attenders revealed CR was not a priority because they were either not interested or were too busy.
The CRNs identified barriers to attendance which mirrored the participants’ responses. CRNs contributed additional insight in that language was another barrier as information delivered to a group in English may be difficult for some to understand. After discussing their perceptions about CR services, the researcher introduced the proposed mHealth exercise program and described how CR information would be delivered by mobile phone text messages supplemented with a website containing video messages from medical professionals and peer role models. Theme 3 revealed participants’ perspectives of the proposed program.
Theme 3: technology can conquer barriers, but can be a barrier in itself
Attenders, non-attenders, and CRNs considered a mHealth program to be an effective way to reach people, particularly for those who could not attend CR due to a lack of time or transport, or due to ill-health.
CRNs highlighted the value and need for a mHealth program because of the high rates of non-attendance at CR sessions. In addition, it was thought that a mHealth approach could reduce existing burden on the hospital exercise CR program. The CRNs discussed how there was a lack of space for patients who would like to attend and a lack of support resources to keep patients on track once the program finished. A home-based exercise program, such as the mHealth exercise program, was viewed as a way to help some patients get started or maintain their exercise routine.
All 38 patient participants stated the mHealth program would be an effective method to deliver CR. Attenders thought the mHealth program was a good opportunity to gain extra CR, while non-attenders felt it could help them make lifestyle changes, such as starting an exercise program. Participants wanted information about what type of exercise to do, how often to exercise, and “helpful tips on little ways to get exercising” (Non-attender).
Participants provided feedback specific to the three components of mHealth: text messages, video messages, and the website. Non-attenders in particular thought the mHealth text messages would motivate them to make lifestyle changes. They felt receiving text messages would push them to do their exercise for the day, even if at times it might be a bit intrusive.
When discussing the role model video clips for the website, participants thought it would be equally important to include medical professionals and clips from patients like themselves who have gone through a similar process. Patients could then learn how people like them have made positive lifestyle changes, which would motivate them to do the same. By seeing that others have been through a similar experience, this could enhance a sense of group membership, something valued highly by CR attenders in theme 1.
A study website with CR information, video clips, and links to other trusted services and sources of information was perceived to complement the text messages. Participants felt it would be beneficial to have a source of information that explained everything in detail, step by step, that could be printed to share with others.
One of 28 attenders (4%) and 3 out of 10 (30%) of non-attenders thought that a mHealth program would be better for the younger generation and people who were frequent mobile phone users. Some participants did not have mobile phones (attenders
=
4/38; non-attenders
=
2/10) or access to the internet and had concerns as they were “not brought up with all that kind of stuff” (Non-attender).
While some participants considered the mHealth program might be of greater value to younger people, not all older participants were of this opinion. There were many instances where participants in their senior years were interested in taking part, but felt they would need some assistance. The 3 CRNs also considered age a potential barrier of mHealth, however with some minimal input, they stated that participants could easily be taught to read texts and access the website. Overall 3 out of 3 of the CRNs and 38 out of 38 patients (100%) considered the mHealth program would be a positive addition to existing CR services.
Initial development of the intervention: applying focus group feedback
Results of the qualitative research were presented to the content advisory group for discussion. Based on the positive feedback the content advisory group considered it appropriate to move forward and develop the HEART intervention (Heart Exercise and Remote Technologies). Specific feedback from the qualitative research was integrated into the mHealth intervention content where possible.
The issue of non-use or infrequent use of mobile phones, particularly by the older population, resulted in additions to the study protocol. It was decided that the SMS intervention would primarily use a ‘push’ approach, so that messages would be sent to participants, requiring minimal input from them or technical ability. In addition, it was decided that researchers would teach participants how to open texts and view messages, and provide assistance to those who encountered difficulties.
Initially we planned to deliver video messages via mobile phones as we had done in a previous study with young people [
21], however formative research revealed 34 out of 38 (89%) participants did not feel confident to access video messages on their mobile phone due to lack of knowledge or the cost of receiving these messages. Accordingly, the intervention was modified to allow delivery of video messages via a secure participant website.
Feedback from the formative research was used to inform the development of the intervention content. In response, a library of text and video messages was developed by investigators (LP, RM, RW, GK), using a Self-efficacy Theory framework [
23] and published exercise guidelines [
24] for people with CVD.
Text messages were categorized according to their exercise prescription or behavioral change focus. Self-efficacy is one’s perceived capabilities to perform a behavior in a certain situation [
23] and is a key psychosocial determinant of adherence to CR [
26-
28]. The intervention text messages aimed to increase participants’ perceived confidence to perform exercise, overcome barriers, and schedule exercise on a daily basis, as well as increase motivation to be active.
Brief (30–60
sec) videoed vignettes of role models were developed for participants to view. Role models were identified by CRNs at various hospitals and at a CR exercise clinic. The videos were unscripted, facilitating role models to deliver their personal stories in a more natural way. Vignettes from cardiologists, cardiac rehabilitation nurse specialists, and exercise physiologists were included, which outlined the benefits of exercise, physiological responses and safety issues.
Study 2: pre-testing study methods
From our library of messages we selected 6 text and 6 video messages to be evaluated by participants using a closed password protected online survey. The chosen messages represented the underpinnings of all messages, which was equivalent to approximately 5% of the total message library. A total of 12 messages were selected to ensure the survey took less than 30
minutes to complete, in order to retain participant interest. The online survey allowed participants to provide feedback about the content of the SMS and video messages and provided a platform to test whether participants could view the videos on their computers. A total of 52 items were asked over 10 pages using adaptive questioning and most questions were mandatory. The online survey was conducted according to the CHERRIES statement [
29], a checklist designed to strengthen the quality of online survey results, and was tested by members of the research team (LP, GK, KC, RW).
Participants were a purposive sample recruited from community CR education sessions over a two month period. They had to have attended at least one session and have access to the internet. This was a different sample from the qualitative study; however two online survey participants had also participated in the qualitative study. Potential participants were sent email invites to complete the survey. Participants received information sheets outlining the purpose and length of the survey, and informed consent was completed online prior to starting the survey.
The survey used LimeSurvey® software and allowed data to be stored on secure servers at the research center. Responses were automatically captured and relevant data were extracted once the target sample size (n
=
20 completed surveys) was reached. Participants who volunteered their time to complete the survey were entered into a draw to win a $100 gift certificate.
Pre-testing study results
Participants were assigned tokens to assure anonymity and unique responses, valid for approximately one month. A total of 41 people registered their interest in participating in the survey, and 28 participated (participation rate
=
68%). Of the 28 submitted surveys, only 20 were found to be complete (71%) and were included in the subsequent data analysis. Three of the 8 participants who did not complete the survey reported technical difficulties viewing the videos. Participant demographics are described in Table .
Survey results revealed that participants generally enjoyed the videos and found them useful. Seventeen out of 20 (85%) participants indicated they would sign up to a CR program that delivered information by video messages on the internet. All 20 participants (100%) could understand the videos and most (95%) could relate to the speakers. Three of the six video clips were perceived as just the right length, while a few participants (3/20, 15%) felt the remaining three clips were too short. Nine out of 20 (45%) participants enjoyed messages from patients like themselves the most, while the remaining preferred messages from exercise experts (30%) or medical professionals (25%), indicating that a combination of the above would satisfy most. No participants were offended by the content of the videos.
Suggestions were made to improve the video messages. Participants felt that younger CVD patients and patients of varying ethnicities should be included. A variety of role models would increase the probability that future intervention participants would be able to relate to a role model, which is an important component for increasing self-efficacy to exercise. Participants also stated they wanted to see demonstrations of different exercises, to learn how to find time to exercise and how to make exercise fun.
Feedback regarding text messages was mixed and mirrored responses from the formative research. Twelve out of 20 (60%) of participants were interested in signing up for a CR program delivered by text message. Participants (19/20, 95%) could understand the messages and appreciated that abbreviations were not used. The texts were seen as a good reminder to exercise but too many messages could be perceived as nagging. Participants appreciated that someone was ‘looking out’ for them and their health, but wanted to be sure they could trust the messages and that they were accurate. Some felt that having both texts and the internet approach with videos would be beneficial. Three out of 20 participants (15%) felt the texts would not be useful to them as they did not carry their mobile phone with them or seldom used it.
Final development of the intervention: applying pre-testing feedback
The intervention was further developed and finalized after the formative and pre-testing research. Twenty-four weeks was chosen as the intervention length to assess long term sustainability of the intervention on exercise behavior. Participants would receive 4–6 text messages per week, using a combination of exercise prescription and behavior change texts aimed at motivating participants to complete their exercise and enhance self-efficacy using approaches such as goal setting, identifying barriers, and developing strategies to overcome barriers. A total of 118 text messages were created for the intervention.
An interactive website was created to provide a platform on which participants could view video and text messages, read information about exercising with CVD, track their exercise progress using a graphing tool, develop goals on a goal setting chart, and develop strategies to overcome obstacles. Additional videos were filmed to include more role models with different backgrounds. Interesting visuals were added to the videos, particularly around exercise tips, including demonstrations of exercises that can be done around the home. One hundred and twelve video messages were created, and 2–8 video messages per week were made available to participants.
A section was also created on the website that described who created the exercise content and how exercise targets were determined. This was done to reassure participants that their exercise prescription was safe, increasing their confidence and self-efficacy to exercise. New content was programmed to appear on the website every 3–4
days. Participants were encouraged to view the website as often as they liked, but logging on once or twice per week would be sufficient. Participants could choose whether to view their text messages on the mobile phone, on the website, or both. Please see Additional file
3 for example SMS and video messages.
Steps were taken to resolve the technical difficulties encountered by some of the online survey participants. For example, instructions written into the study protocol meant researchers could demonstrate how to log on to the study website and view the videos. The website was tested on different computer systems and Internet browser versions to ensure that content could be accessed on older computers. A help section was also created on the study website, as well as contacts for technical difficulties.
Pilot study and randomized control trial
Pilot testing of the intervention was integrated into the full randomized controlled trial (n
=
170). During the study, the first 10 study participants were closely monitored for 6-weeks to ensure they received the automated program of SMS and video messages and to resolve any technical issues that arose. In addition, the first author and two co-authors (GK and KC) received all text messages in advance of intervention participants to help identify and resolve technical issues in a timely manner. Full details of the RCT protocol have been published [
19] and the trial began in mid-2011.
1 Ralph Maddison,1 Robyn Whittaker,1 Ralph Stewart,2 Andrew Kerr,3 Yannan Jiang,1 Geoff Kira,1 Karen Carter,1 and Lance Dalleck4
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