2.1 General
The target group of geriatric patients often has difficulties accessing existing technology, which can lead to the exclusion of this vulnerable group from some technologies. For this reason, a user-centered design is indispensable for older chronic back pain patients. In order to create user-friendly, adaptive, personalized system that is tailored to the target group, we conducted a requirements analysis as a first step.
The study had an explorative, qualitative approach. In addition, quantitative assessments were only used for gathering baseline data from the CBP. The study consisted of two focus group interviews with three physiotherapists and with two psychotherapists and semi-structured interviews with 10 geriatric CBP patients. The purpose was to find out the expectations, desires, preferences and barriers of this vulnerable group and the experts. The study protocol was approved by the ethics committee and data protection committee of the Charité. All participants gave their written informed consent to take part in the interviews.
2.2 Procedure
2.2.1 Interviews with older CBP patients
The purpose of first part of the qualitative study was to assess the requirements of a VR exergame for geriatric patients with CBP. The sample (n=10) consisted of older adults over 65 years with diagnosed chronic back pain. Interested persons were first informed about the study in a telephone call and then, if accepted, asked about inclusion and exclusion criteria in a screening. After initial screening and formal inclusion, the participants completed an informed consent form, the SF-12 Health Survey (Short Form 12 German translation) and the chronic pain grade questionnaire (CPGQ). Subsequently semi-structured interviews were conducted in order to investigate the requirements of the seniors. The semi-structured interview guideline created by the Geriatrics Research Group included the following main content categories:
- sports and gymnastics practiced in the past and today,
- sport as social participation,
- problems and difficulties in activities of daily life,
- strategies for dealing with pain,
- game experiences and preferences (traditional and digital games),
- hardware and software requirements for a VR exergame
- requirements for motivational elements.
The interviews with the CBP patients lasted 40-60 min and were divided into three parts; a first part for personal requirements, a second in which the subjects tested a user experience demo in a VR environment, and a third concerning the requirements for a VR pain therapy system. Afterwards the interviews were transcribed and analyzed. The Ethics Committee of the Charité approved the study protocol (no. of approval: EA4/055/18).
2.2.2 Focus Group
The second part of the qualitative study included two focus groups. The intention was to gather framework data and requirements from physiotherapists (n=3) and psychotherapists (n=2) who have expertise in older CBP patients. The partly standardized focus group interviews were carried out with guidelines, which included questions on pain management experiences and games applications in therapy. The first part of the guidelines included the following sub-topics:
- Experience in the treatment of chronic pain patients,
- adherence of patients (physiotherapists) / overcoming the fear-avoidance behavior (psychotherapists),
- acceptance and experience with game applications in pain therapy.
Subsequently, a short film sequence about Virtual Reality Therapy was presented to show already existing concepts. The second part of the guidelines included questions about requirements for a VR therapy system with the following sub-topics:
- Software (patient’s UI), software (therapist’s UI),
- hardware,
- and communication with therapists / forwarding of data.
The survey in the focus groups lasted 1-1.5 hours.
2.3 Materials
2.3.1 Assessments
The SF-12 Health Survey tested on older adults was found to be reliable and valid [23]. Likewise, the chronic pain grade questionnaire is a valid and reliable tool. The internal consistency shown with Cronbach’s alpha = 0.74 for chronic back pain was determined by Korff et al. [24]. The study of Penny et al. [25] had shown a relationship between the CPGQ score and the Short Form 36 Health Survey (SF-36). The results of the study confirm that a higher chronic pain grade is associated with poorer health in all aspects such as poorer physical, psychological, and social health, which supports a multimodal pain management approach.
2.3.2 VR Headset
During the task-based part of the semi-structured interviews the seniors and experts tested two applications on the Dell Visor VR118 Headset. This headset has a 105-degree horizontal field of view and a display rate up to 90 Hz. This VR headset was chosen because of the two high-resolution displays at 1440 x 1440, so that the testing group was not exposed to cyber sickness.
2.3.3 VR Apps
In order to create a common understanding for VR in the sample of seniors an exergame user experience prototype was used (Figure 1). In the prototype, the player stands on a platform on a lake and has to collect pink coins. These appear for a short time around the player. The player’s straight posture is determined by the headset height at the beginning of the application, and subsequent malposition of the back turns the player’s surroundings from a colorful landscape to black and white one. The software prototype did not contain any other gamification aspects, e.g. a story, in order not to influence the user’s requirements on this topic.
The second application was the HoloTour by Microsoft Corporation. The aim was that the player experiences the feeling of immersion in a realistic-looking virtual space.
2.4 Data Analysis
The interviews with the seniors were recorded and subsequently transcribed using the transcription software f4. A summarizing content analysis by Mayring (Mayring 2015) was applied for the data analysis. As an analyzing tool, we used the qualitative data analysis software Atlas.ti 8. The structuring content analysis contains paraphrasing, generalization to abstraction level and reduction. The transcripts were coded manually according to specially drafted coding rules. The coding was carried out by two scientists, using the four-eyes principle to ensure reliable coding. The coding and analysis were controlled reciprocally. A total of 130 codes were assigned and 1329 quotations were classified as relevant.
2.5 Participants
2.5.1 Chronic back pain patients
10 participants with CBP were included in the semi-structured interviews. One subject had to be excluded from the study. The inclusion criteria were:
- Geriatric patients with chronic back pain longer than 6 months
- ≥ 65 years
- No cognitive impairments
- Independent mobility
- Able to perform exercises actively
- No spinal malignancies, spondylitis and spondylodiscitis, fibromyalgia
- No disc surgery in his or her medical history
- No strong vestibular disturbances that affect balance ability
The exclusion criteria were defined as:
- Patients with chronic back pain shorter than 6 months
- <65 years
- Cognitive impairments
- Immobility or mobility only possible with help
- Sensory and / or motor impairments
- Unable to do exercises actively
- Spinal malignancies, spondylitis and spondylodiscitis, fibromyalgia
- Disc surgery in his or her medical history
- Strong vestibular disturbances that affect balance ability
On average the CBP patients were 75.9 years (SD 6.9) old. Seven participants of the sample had a low disability and a low intensity of pain, corresponding to Grade I in Von Korff’s chronic pain scale [24]. The pain severity of one participant was classified as Grade II, which means: low disability and high intensity. Two participants had a high disability, which is moderately limiting and corresponds to Grade III. None of the probands’ pain was classified as Grade IV with a high disability, which is severely limiting. All participants had back pain for more than six months and were able to perform exercises actively. None of the subjects had cognitive limitations or severe balance limitations. The subjects had in the Short Form (12) Health Survey, which is a shorter version of the SF-36, a mean mental health score of 53 (SD 8.0) and a physical health score of 37 (SD 10.7) on a scale from 0 to 100. Both mean values of the SF-12 are slightly higher than the comparative values of patients with lumbar back pain (mental health: 47.3 and physical health: 35.1) [26]. In a questionnaire for the subjective evaluation of technology use, the majority of subjects (n = 6) stated that they frequently use their technology devices. All subjects stated that they use a telephone and a radio. As VR still requires a PC or at least a smartphone, the question of PC and smartphone usage has been an important clue to starting conditions in the sample. Eight subjects stated that they use a PC and six that they use a smartphone.
2.5.2 Experts
As physiotherapists and psychotherapists are an important part of multimodal treatment teams, they have been included as experts concerning the requirements of a potential VR exergame. The inclusion criteria were:
- Experience in the treatment of chronic back pain patients
- at least 3 years professional experience with back pain patients
- Currently working as physiotherapist or psychotherapist
Two focus group interviews were conducted, one with three physiotherapists and one with two psychotherapists. Among the physiotherapists, two of the participants are employed in a geriatric rehabilitation clinic and one in a physiotherapy center. The professional experience among the physiotherapists was between 4 and 10 years. The second focus group was attended by two psychotherapists, one of whom works in a clinic with focus on acute geriatric medicine and one who owns a psychotherapy practice. The professional experience of the participants was 6.5 and 14 years.
2.6 Prioritization of the requirements
The requirements analysis summarizes the requirements determined in a catalogue, which is the basis for the conception of the joint project and the further structuring of the VR training program. In order to create a common understanding among the stakeholders about the importance of the requirements, a prioritization was carried out. Following the content analysis, the reduced requirements of the semi-structured interviews and the focus groups were prioritized by six CBP patients, three physiotherapists and one psychotherapist. The prioritization procedure (Figure 2) was based on Moisiadis’ prioritization method (Moisiadis, 2002). The prioritization aimed at a self-prioritization and external prioritization of the requirements by various stakeholders. Rankings of 1 to 3 were used to determine the rankings of the three stakeholders (1= CBP patients, 2= physiotherapists, 3= psychotherapists) for the overall project and for each of the four dimensions (overall system, hardware, software, gamification). A weighting for the requirements was calculated from the rankings for the overall project. The requirements in the four dimensions were also ranked according to their subjective importance and calculated with the weighted stakeholder factor. Within the stakeholder groups, mean values were used to determine the average stakeholder ranking for the requirements, resulting in a ranking of the requirements per stakeholder that could be compared between the stakeholders. The stakeholder rankings in the dimensions made it possible to determine a “winner stakeholder” for each dimension. The requirements of these stakeholders were subsequently included in the catalog of requirements for each dimension and evaluated again by the consortium using the MoSCoW prioritizations [27] according to the project relevance.
2.7 Weighting of the requirements
In order to evaluate the importance of the opinion of the expert groups involved (CBP patients, physiotherapists, psychotherapists) for the overall project, the stakeholders were rated. Profile models similar to Moisiadis’ prioritization method were created for the stakeholders. As part of the prioritization process, the stakeholders were assessed by the participants using subjective and objective ratings. All participants were involved in advance in the interviews to determine the requirements. The rankings were subsequently decoded, with 3rd place receiving 0 points, 2nd place 50 points and 1st place 100 points. Afterwards a weighting was calculated from the mean values of the scores. The evaluation showed that the physiotherapists achieved 1st place and the psychotherapists and CBP patients achieved 2nd place together. The physiotherapists received a 1.75 times higher rating than both other stakeholders, which resulted in a factor of 1.75 for further rating of the four dimensions. The further dimensions, which were ranked on a weighted basis in addition to the overall project, were: overall system, hardware, software and gamification. The categories will be presented in the following.