This project the perceived usability of the Virtual Reality (VR) system, CropHarmony, designed to help older adults maintain mobility. With an aging population and increasingly sedentary lifestyles, the potential of VR technology to promote Physical Activity and counteract health problems is a current topic.
This project uses a mixed methods approach combining qualitative interviews and quantitative data from the System Usability Scale (SUS). The qualitative results provide insights into the participants' experiences, focusing on the technical aspects, integration of movement, and emotional reactions.
The quantitative analysis of the SUS ratings highlights areas for improvement and emphasizes the importance of refining system complexity.
The study contributes to the understanding of the specific needs of older users. It provides insights for future studies to improve VR systems and their design, considering technical and user experience aspects.
This project utilizes a case study approach as a research strategy. Case studies provide rich, detailed descriptions and insights into specific cases that fit well with our research question, which concerns the different perceptions of older people towards CropHarmony. A common criticism of case studies is that their findings are limited to the specific case studied and may be less generally applicable. To enhance the applicability of our case study findings, we adopted several strategic approaches, including purposive sampling, to ensure a diverse participant background. This approach aligns with current developments in social VR gaming for older users, as outlined by Shah et al., and addresses concerns about limited generalizability.
This study uses a mixed data collection approach, including qualitative and quantitative methods. Following the approaches of Creswell and Johannesson & Perjons, qualitative semi-structured interviews allowed us to collect detailed and complex information, complemented by direct observation of participants interacting with the VR application.
In addition, we used the System Usability Scale (SUS) survey, a widely recognized usability assessment tool for collecting quantitative data, which contains ten questions on various usability aspects. In qualitative research, careful selection of participants is critical, as participants must have certain characteristics relevant to the research question. In this study, a non-probability sampling method focused on a specific subset of the population to investigate a specific topic: the perceived usability of older people regarding CropHarmony.
This non-probability sampling approach used purposive sampling to refine the participant selection process. Purposive sampling selects participants who meet the necessary criteria to provide the insights sought. Therefore, this approach is sometimes called "judgment sampling". It is important to note that this type of sampling can lead to bias. Selection based on predefined criteria raises questions about the sample's representativeness and may question the ability to theoretically, analytically, and logically generalize the results, as using a different population could yield different results.
In order to avoid the biases mentioned above, criteria have been established that participants must meet. One of our teachers forwarded us the contact details of a woman living in a collective house for the elderly. Our established criteria were forwarded to this contact, who then posted an information sheet in the collective house. This information sheet included a description of the project, our contact details, and the criteria the participants must fulfill. Ten participants volunteered to participate in the user testing.
A thematic analysis is carried out according to the iterative process described by Bazeley to analyze the qualitative data obtained from the interviews. The transcription was done manually to familiarize oneself with its content from the outset. The coding and theme development were done in Miro, a collaborative design platform. Passages of the interviews were marked with color codes. These codes were adjusted by reading through the interviews several times and finally combined into main themes. The SUS scores obtained from the participants' responses were aggregated and statistically analyzed in Excel to measure the perceived usability of the VR training system. Individual SUS scores were calculated for each participant by summing the scores obtained from the ten statements and multiplying the total by 2.5. This step results in an individual SUS score from 0 to 100. The individual scores are combined to find the mean SUS score for the whole test group. This mean score serves as a quantitative measure of the perceived usability of the VR training system. Scores above 68 are generally considered above average, while scores above 85 are considered excellent in terms of usability. Scores below 50 suggest significant usability issues. Standard deviation was calculated to assess the variability in SUS scores among participants, indicating divergent opinions. The analysis of SUS scores will help evaluate how older adults perceive the usability of the VR training system and identify areas where improvements may be needed.
This study investigated the perceived usability of the VR training system, CropHarmony, designed to assist older adults in maintaining their mobility. A mixed methods approach combining qualitative interviews and quantitative SUS scores was used to comprehensively understand participants' experiences and preferences. The qualitative analysis revealed three main themes: VR Environment and Technical Factors Influencing System Use, Perceived Suitability of the VR System for mobility training, and Emotional factors influencing the perceived usefulness of the system. These themes highlighted the intricate interplay between technical aspects, exercise integration, and emotional responses, providing valuable insights into the system's usability.
The first theme highlighted challenges such as interaction issues and problems with visibility and emphasized the importance of refining technical nuances. The second theme emphasized participants' desire for more complex and varied exercises, pointing to the need for customized experiences geared toward the different needs of older users. The third main theme illustrated the emotional impact of the VR system, with participants expressing a range of feelings from excitement to a desire for more realism.
In quantitative terms, the System Usability Scale (SUS) resulted in an overall mean score of 56.5, below the target score of 68, indicating areas where the system's usability could be improved, as six out of ten participants rated the system below average. The analysis of the individual SUS questions revealed that in certain areas, such as the desire for frequent use and the need for technical support, improvements could have a significant impact on user satisfaction.
Our research question can be answered by synthesizing qualitative and quantitative results. The study has shown that while CropHarmony is a promising tool for promoting PA in older adults, its usability needs to be improved. The participants generally found the VR environment pleasant but pointed out technical problems that impaired user-friendliness. The suitability for mobility training was affirmed, but participants desired more intensive and varied exercises. Emotional reactions, both positive and critical, played a decisive role in the perception of the system's usefulness.
The quantitative SUS evaluations supported these findings and indicated a general need for improvement in usability. While certain aspects met the target, others fell below expectations, particularly regarding the desire for frequent use and confidence in using the system. In conclusion, the study highlights the importance of addressing technical subtleties, diversifying exercises, and enhancing emotional impact to optimize the usability of VR exercise systems for older adults.
These findings contribute to the ongoing discussion on using technology to promote PA, mobility, and general well-being in the aging population. Future studies can use these insights to explore a collaborative MR approach to enable haptic feedback and work on technical subtleties such as grasping or pressing objects.
