In recent years, there has been a surge in groundbreaking technologies and their applications in transforming care, therapies, treatments, and health prevention for older adults. Fully immersive virtual reality (FIVR) is one among these rapidly evolving technologies applied in diverse interventions, including poststroke rehabilitation [1], cognitive training for people with neurodegenerative diseases [2], mobility and balance training [3], and the reduction of depression [4]. This paper examines the application of FIVR in reminiscence interventions through a scoping literature review, with a particular focus on people living with dementia or mild cognitive impairments.

Reminiscence intervention is a type of nonpharmacological therapy [5] that was developed in the 1960s and has gained popularity since the 1980s [6]. Reminiscence is an act of recalling or retelling past experiences or facts [7]. As an early advocate of this technique, Butler [8] argued that reminiscence was an older person’s natural adaptive response to late-life developmental crises, with thoughts related to their approaching death. Used in life review therapy, reminiscence helps an older person reorganize past experiences, settle unresolved issues, bring new meaning to the present life, and better prepare for death [8]. Molinari [9] expanded on the notion proposed by Butler [8] and purported that reminiscence activities could take many forms, including storytelling, autobiography, music, reunions, and scrapbooks. He suggested that reminiscence could be conducted in community or clinical settings, with a person or group of people, by laypersons, or by trained professionals; with structured or unstructured methods; or in a formal or casual format [9]. However, many states in the United States, such as Texas, require counseling therapy to be delivered by licensed professionals [10]; interventions done by family members, friends, and noncertified personnel may be referred to as informal exercises or activities.

Pinquart and Forstmeier [11] and Woods et al [12] identified three main types of reminiscence interventions: (1) simple reminiscence, which involved the recall and sharing of positive memories and stories to increase positive feelings; (2) life review, which was conducted in a structured way with the whole-life story, seeking to integrate both negative and positive memories; and (3) life review therapy, which typically aimed at the reevaluation of negative memories, promoting a more positive view of life.

According to Molinari [9], reminiscence interventions help reshape a person’s views of life experiences and stories toward positive and coherent outcomes, focusing on strength, success, and lessons learned. Therefore, reminiscence interventions have been used in diverse settings for various purposes: in dementia and Alzheimer care to lessen behavioral and psychological symptoms and enhance cognitive function, social interaction, self-esteem, and quality of life [12,13]; in end-of-life care, such as hospices and palliative care, to enhance life satisfaction and reduce feelings of regret [14]; in patients with cancer to lower anxiety and depression scales and increase hope, dignity, and quality of life [15]; and in rehabilitation to motivate patients to actively participate in the rehabilitation process, fostering a sense of identity and continuity in their life story [16]. Moreover, a literature review conducted by Shin et al [17] revealed that a reminiscence intervention was effective in improving the quality of life and life satisfaction among community-dwelling older adults with no dementia symptoms.

Similar to other psychotherapeutic interventions, a reminiscence session is primarily carried out through conversations, with a provider guiding the person to recall past events, discuss their meanings and impacts, resolve past conflicts, and pave the way for more positive views of the present life. Various media or artifacts that provide visual or audio cues have been applied to stimulate memory and prompt conversations, especially for those with memory problems.

In a literature review, Lazar et al [18] reported that common media for reminiscence interventions included text, videos, photographs, images, music, audio, and personal objects and artifacts such as toys, which were closely related to the person’s past experience. The authors also revealed that the technologies to present these media ranged from slide projectors and tape recorders from the 1990s to touchscreen tablets in the early 2010s [19-21]. Moreover, digital technologies have since created more innovative alternatives to aid reminiscence [22-25]. For example, personalized digital memory books and multisensory mobile multimedia environments delivered more content or multiple stimuli in convenient ways [26].

Figure 1 [19-25,27] shows the timeline of different technologies used in reminiscence interventions since 1992. It is worth noting that therapists may have used technologies to aid reminiscence activities in earlier years, but this was not documented in peer-reviewed publications.

Virtual reality (VR) uses computer simulation to provide realistic visual and tactile experiences in a 3D virtual world. VR appears in many forms: (1) nonimmersive, in which a computer or television screen is used to display the content; (2) semi-immersive, in which multiple screens or a Cave Automatic Virtual Environment display present the virtual environment surrounding the participant [28]; and (3) fully immersive, in which the participant wears the VR head-mounted display or haptic devices to be fully immersed in the virtual world. According to Logan [29], VR possesses three main characteristics: (1) interactivity, whereby the user can interact with the virtual world through commands; (2) immersion, whereby the user should have similar authentic feelings, through different sensors, such as those in real environments; and (3) imagination, whereby the user should be able to imagine beyond the virtual world, finding new perspectives or new ways to solve problems.

VR has been applied in a variety of interventions for older adults. D’Cunha et al [30] conducted a literature review on the application of VR and augmented reality in nonpharmacological interventions, examining their effectiveness in promoting psychological health and users’ experience. Three types of interventions were tested in the reviewed studies: (1) cognitive or memory training; (2) reminiscence; and (3) therapeutic activities, including physical exercises. The results showed that VR and augmented reality were preferred and well accepted by people living with dementia or mild cognitive impairment and that these technologies helped improve mood, apathy, and cognitive functions. However, some side effects raised concerns about negative feelings after the reminiscence sessions that triggered participants’ unpleasant memories. Although immersive VR was used in some studies selected by the authors, most of them were semi-immersive but did not use a head-mounted display that would provide a fully immersive experience.

Although the first head-mounted VR display with 3D graphics and head tracking was invented in the 1960s [31], it was not until the last decade, marked by the introduction of the first consumer-grade VR headset (Oculus Rift) in 2011, that FIVR became more affordable, more technically accessible, and easier to use [32]. FIVR has been popular in a variety of fields such as gaming, education, professional training, medical practice, therapies, and research [33-37]. With its capability to promote interactivity, immersion, and imagination, FIVR may be an excellent aid for reminiscence interventions by stimulating or reactivating the past memories of older adults, especially those living with mild cognitive impairment or dementia.

Population aging has brought about a rapid increase in the number of older adults with cognitive and behavioral problems. Rajan et al [38] estimated that 12.23 million Americans aged ≥65 years experienced mild cognitive impairments in 2020 and that this number would rise to 21.55 million in 2060. The Alzheimer’s Association reported that 10% to 15% of people with mild cognitive impairment transitioned to dementia each year [39]. Furthermore, approximately 1 in 9 older adults (10.7%) in the United States had Alzheimer disease, accounting for 60% to 80% of people living with dementia. Cognitive impairment affecting memory, language, orientation, attention, and judgment leads to behavioral and psychological disturbances, dysfunction in activities of daily living, and instrumental activities of daily living [40-42]. Such functional disabilities and behavioral problems have added to caregivers’ and family members’ burdens and strained health care resources [43].

According to the Alzheimer’s Association, pharmacological and nonpharmacological options may be available to treat cognitive impairments, depending on their causes [39]. However, pharmacological treatment options are limited, with only 6 drugs—specifically for Alzheimer disease—currently approved by the US Food and Drug Administration [39]. In addition, there is evidence that pharmacological treatments for behavioral and psychological symptoms of people living with dementia often come with adverse side effects, including an increased risk of falls and fractures, stroke, and even mortality and limited efficacy in symptom management [44]. Nonpharmacological therapies are safer options with manageable side effects for people with cognitive impairments than pharmacological treatments. These therapies can help reduce anxiety, depression, apathy, irritation, and other negative emotions and possibly decrease the need for pain and psychoactive medications by not inducing biological changes [45]. After reviewing the literature, Cammisuli et al [5] categorized nonpharmacological interventions into four main categories: (1) holistic techniques, including reality orientation that helps people living with dementia be aware of who and where they are and what time it is; cognitive stimulation therapy that uses a series of objects, themes, or activities, such as physical games, sounds, food, current affairs, scenes, word association, using money, and number games to stimulate cognitive functioning; and reminiscence; (2) brief psychotherapies, a type of psychodynamic therapy that emphasizes the identity of people living with dementia through a conversation about past experience, with the aim of reducing emotional distress and other behavioral problems; (3) cognitive methods, such as the space retrieval technique, which trains people living with dementia to regain the ability to associate names with human faces or with objects; and (4) alternative strategies, such as music therapy and bright light therapy [5].

As previously noted, Cammisuli et al [5] categorized reminiscence interventions as a holistic technique of nonpharmacological therapy. Evidence has shown that appropriate reminiscence interventions for older adults with cognitive impairment can effectively evoke memories, alleviate anxiety and depression, reduce stress, manage cognitive decline, increase self-esteem, and improve quality of life [11,46,47]. Importantly, these interventions may potentially lower caregivers’ burden and stress due to the improvement in their care recipients’ psychological, mental, and behavioral health [48], which is significant as the world is experiencing a serious shortage in the nursing workforce.

We found little collective knowledge on how FIVR works in reminiscence interventions. Therefore, this scoping review aimed to assess and synthesize existing evidence regarding the influence and effectiveness of FIVR as an aid in reminiscence interventions. We expected the findings to elucidate potential directions for future research, offer recommendations for practice, and address the critical needs of caring for frail older adults, particularly those living with dementia and mild cognitive impairments.

We adopted PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analysis extension for Scoping Reviews) to map the evidence for FIVR-based reminiscence interventions. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) is a minimum set of evidence-based items for reporting in systematic reviews and meta-analyses [49]. The PRISMA-ScR—with 20 essential reporting items and 2 optional items—was created to synthesize evidence and assess the scope of the literature on a topic [50]. The detailed descriptions of the 22 items are reported in Multimedia Appendix 1. Compared with systematic reviews, scoping reviews address a broader research question [51]. They allow researchers to identify the scope of the literature in a certain area, provide a clear indication of the available literature and an overview of its focus, and examine emerging evidence that informs field practice [51]. We adopted the scoping review approach because it perfectly aligns with our study’s aims.

We applied the following inclusion and exclusion criteria for article selection: (1) the use of FIVR as an aid for reminiscence interventions; (2) the inclusion of adults aged ≥65 years; (3) reporting on empirical studies; (4) reporting on outcomes related to health and well-being and the feasibility or usability of FIVR; (5) publication in English; and (6) publication in peer-reviewed journals or peer-reviewed conference proceedings between January 1, 2000, and August 1, 2022. Electronic databases—PubMed, PsycINFO, Embase, CINAHL, Web of Science, ACM, and IEEE Xplore—were used for the literature search. The search terms included all possible synonyms and combinations of “Reminiscence Interventions and/or Therapies” (reminiscence, life story, reminisc* therapy*, and memory simulation) and “Virtual Reality” (VR, imagined 3D environment, and simulat* environment).

First, a researcher used a consistent set of keywords to search each database between March and August 2022. The search results were imported and organized using Endnote X9 (Clarivate), a computer reference management program. Second, 2 researchers scanned the titles and subsequently the abstracts of the retrieved articles. They then independently reviewed the full texts, collating all eligible articles. References from these articles were also scrutinized to capture any potentially overlooked information in the initial database search. Subsequently, the researchers deliberated each article in detail, deciding on its inclusion based on predetermined criteria and the study objectives. In case of any disagreements between the 2 researchers, a third researcher was ready to intervene with a final decision. However, this contingency was not triggered.

We continued to use Endnote X9 to manage the selected articles and Microsoft Excel spreadsheets for data extraction. The categories of the data included title, author, year of publication, publication type such as journal or conference paper, research design, research questions, intervention information including reminiscence types, VR contents, VR types, and devices, and participant information, measurements, results, study limitations, and future research questions. One researcher charted the data into a spreadsheet, whereas another oversaw the process, critically assessed the extraction, and made necessary adjustments based on joint discussions when a disagreement arose. The charted data were further summarized and analyzed by both researchers.

The screening and selection process for eligible articles is shown in Figure 2. Additional details can be found in Multimedia Appendix 2. The first search resulted in 742 articles from the databases and 64 others from further sources such as references of selected articles. After removing the duplicates, 700 articles were retained. After the authors screened each article’s title and abstract, 174 articles remained in the pool. We quickly scanned the full text and retained 56 articles for additional evaluation. Through the detailed full-text reviews, 45 studies were excluded according to the inclusion criteria, with specific reasons documented in Figure 2. Finally, 11 studies were identified for this scoping review [25,40,52-60].

Table 1 summarizes the general information of the selected studies, including basic article information such as authors, year of publication, and research design.

Nine articles were published in peer-reviewed journals and 2 in peer-reviewed conference proceedings. There were 4 studies that were conducted in Australia [53,56-58], 4 in Asia (China, Taiwan, and Japan) [54,55,59,60], 2 in Europe (Germany and Portugal) [25,40], and 1 in the United States [52]. The years of publication were between 2018 and 2022.

Table 2 lists the participant characteristics of the included studies. All the studies involved older participants, with an average age between 80 and 90 years in 6 studies and 70 and 80 years in 3 studies. Two articles did not specify the participants’ ages. All but one study included participants with cognitive impairments. Three studies specifically stated that they recruited people living with dementia [40,53,59]. Three studies reported other health problems in their participants, including depression, anxiety, heart diseases, mental health issues, mobility challenges, hearing difficulty, Parkinson disease, and stroke [54,56,57].

There was 1 randomized crossover trial [55] and 1 randomized controlled trial [59]. Two quasi-experiments with pre-post comparisons were included [56,57], one of which had a control group. Another quasi-experiment was conducted with pre-post comparisons, wherein the intervention was offered twice a week over a 3-month period. Assessments were performed immediately and 3 to 6 months after the intervention [53]. The remaining studies included 3 qualitative studies [30,43,47], 2 mixed methods studies [40,52], and 1 case study [60]. The sample sizes ranged from 2 to 43.

Tables 3 and 4 summarize the VR-related information of the selected studies, including VR types and visual contents, outcome measures, measurement methods, and results.

The VR goggles developed by Oculus were used in most studies (n=8): Oculus Go in 5 studies [52,55,56,58,60], Oculus Rift in 2 studies [40,54], and Oculus Quest in 1 study [57]. Coelho et al [40] used Samsung Gear VR as a head-mounted display in addition to the Oculus Rift. Xu and Wang [59] adopted the HTC VIVE Focus headset. Huang and Yang [53] used the HTC VIVE Pro version. Klein et al [30] developed a VR goggle—the “Binoculars” prototype—for their own project.

We divided FIVR stimuli into three categories: (1) photo based, which used 360° photos of real environments; (2) video based, which used 360° videos of real environments; and (3) computer graphic based, which used 360° images or animations of virtual environments generated by computer 3D modeling programs. Seven studies used photo-based VR stimuli [25,52,55-58,60]. Five studies used computer graphics–based VR, one of which incorporated recorded customized narrative and simple interactive functions via VR handles [52-55,59]. Two studies applied video-based VR [3,30], whereas 3 adopted ≥2 types of VR stimuli [25,52,55].

Only the study conducted by Saredakis et al [57] specified the type of reminiscence intervention used: a semistructured simple reminiscence approach emphasizing positive memories. The 2 other possible approaches, “life review” and “life story review,” were not found in the rest of the articles.

Reminiscence interventions in the selected studies can be categorized based on the way they were conducted (group or individual) and the people involved (certified therapists, caregivers, or researchers). Eight studies were conducted using an individual format. Only the study by Baker et al [54] investigated how VR applications facilitated group reminiscence, in which participants communicated with each other and with a facilitator who was determined before the conversation started. During the interventions, 5 studies used researchers as facilitators [40,53,56-58]. One study used a professional team comprising pharmacists, an occupational therapist, a clinical psychologist, a certified psychologist, and a pharmacy student [60]. Interventions in 2 studies were conducted by researchers accompanied by caregivers or nursing staff [55,59]. All but 2 were conducted only through face-to-face meetings [52,60]. Participants in the study by Afifi et al [52] experienced the FIVR scenarios simultaneously with their family members who lived at a distance, interacting with each other remotely.

All studies reported health- and behavior-related outcomes after reminiscence interventions. For the participants, we identified seven types of health- and behavior-related outcomes reported in the studies: (1) anxiety, (2) apathy, (3) cognitive functions or dementia status, (4) engagement, (5) depression, (6) loneliness, and (7) fatigue.

Two studies concluded that FIVR reminiscence interventions did not significantly affect participants’ perceived quality of life, as assessed by the European Health Interview Survey–Quality of Life (EUROHIS-QOL) 8-item Index and the Quality of Life in Alzheimer Disease 13-item Scale [40,57].

Caregivers’ burdens were examined in 2 studies. Yahara et al [60] found that the FIVR reminiscence intervention reduced caregivers’ burdens, but Huang and Yang [53] reported no significant differences in the caregiver burden scores before and after the intervention.

The usability and acceptability of FIVR in reminiscence sessions were evaluated using various methods such as a self-report questionnaire [55], behavior observation and analysis [25,40,52], and interviews [58]. Most participants indicated that FIVR reminiscence effectively evoked their past memories and was both enjoyable and acceptable. However, 1 study reported that FIVR triggered unpleasant memories in several participants [58].

Of the 4 studies addressing adverse effects, Saredakis et al [56] reported “some” negative symptoms or side effects. In contrast, the other 3 studies found “no simulator sickness” [40], “no significant side effects/discomfort” [57], and “negligible sickness symptoms” [59].

Four studies included caregivers and family members as participants [25,40,58,60]. Both Coelho et al [40] and Webber et al [58] observed that caregivers and family members viewed the FIVR reminiscence experience as potentially beneficial and valuable. However, 1 study [25] noted that caregivers found the reminiscence intervention impractical in an ambulant daycare setting because of the lack of staff for individual sessions.

Three studies compared different effects between the applications of FIVR and other technologies in reminiscence sessions [57-59]. Two studies found that the use of FIVR and a flat screen for reminiscence did not result in noticeable differences among participants [57,58], although participants in the study by Saredakis et al [57] preferred the FIVR experience over a flat screen. Xu and Wang [59] reported that both FIVR and printed photos could elicit the recall of autobiographical memory with no significant difference. However, the participants experienced greater pleasure in FIVR than in printed photos. In addition, Yahara et al [60] compared remote and in-person FIVR sessions and found no significant differences in terms of effectiveness.

All selected articles but one discussed their study limitations. Common limitations across multiple studies were (1) small sample size [40,52,53,55,57,60], (2) the absence of a control or comparison group [40,52,53,56], and (3) participant selection bias [53,57,58]. Other limitations were related to self-report errors [56,60], the lack of long-term or follow-up assessment [40,52], the unavailability of validated assessment tools for specific components [40], being affected by the COVID-19 pandemic [57,60], exclusion of participants with severe cognitive impairments [57,59], and imperfect FIVR contents [53,55].

The authors advocated for a well-designed study with control or comparison groups, an adequate sample size, and follow-up or long-term assessment for future research on FIVR reminiscence interventions [25,40,55,56,59,60].

They also identified an extensive range of future research directions, encompassing 16 directions across 6 aspects:

In total, 11 articles [25,40,52-60] detailing empirical studies on FIVR reminiscence interventions in older adults were selected for this review. All but 1 study focused on individuals with cognitive impairments or dementia. The results showed that the intervention enhanced engagement and reduced fatigue. Although some studies reported positive effects of FIVR reminiscence sessions on participants’ anxiety, apathy, depression, cognitive functions, and caregiver burden reduction, the results were not consistent across all studies. Moreover, FIVR showed overall usability and acceptability with manageable side effects among older adults.

Overall, the review results demonstrated that FIVR-assisted reminiscence interventions, as a nonpharmacological option, were effective in improving some health- and behavior-related outcomes such as engagement and fatigue in older adults. Their effects on depression, anxiety, and apathy were not consistent. There were no significant impacts on other measures such as cognitive functions or dementia status, quality of life, and loneliness. However, it may be too soon to conclude that FIVR may not help induce further health benefits through reminiscence activities, as only 11 studies with small sample sizes and limited time frames were included in this review. Additional studies are required to provide a clearer understanding of this topic.

Most participants in the selected studies felt that the FIVR technology was acceptable and enjoyable. However, a study reported that reminiscence interventions may induce negative memories leading to undesirable feelings or undesirable health results [58], which raised the alarm about the selection of visual content. Otherwise, the side effects of FIVR were deemed manageable, with only a few cases reporting motion sickness. According to Chang et al [62], VR motion sickness includes symptoms such as eye fatigue, disorientation, and nausea, which are often caused by viewing dynamic content. The authors contended that motion sickness usually occurred when a person is immersed in moving VR scenes that yields an illusory perception of self-motion but their body is still in a static (standing or sitting) state. Other causes of motion sickness may be related to the fidelity of the VR stimuli and human factors [62]. Although human factors such as genetics and brain reactions may not be easy to change, the fidelity of VR stimuli can be improved, for example, by increasing the resolution or realistic sense of the visual content. There are many web-based platforms offering rich VR resources such as YouTube and Google Street Views, which were adopted by some selected studies. However, this type of content may not be ideal considering some quality problems such as distortion, glare, and low resolution. Several studies selected for this review used this content as stimuli but did not discuss quality issues in their articles.

Globally, there is a serious shortage in the nursing workforce; consequently, people living with dementia or mild cognitive impairments or other chronic diseases are usually cared for by informal caregivers, most of whom are family members. The care time was approximately 27.1 hours per week per person in 2021 [39], which is a burden on caregivers, especially those who provide informal care but still need to work for a living. This burden may be exacerbated as the person experiences further decline in cognitive functions along with an increase in behavioral problems and the loss of independent living. The selected studies revealed that caregivers viewed FIVR-assisted reminiscence as beneficial and valuable for people living with mild cognitive impairments and dementia. The effects of such interventions on anxiety and apathy may potentially lower caregivers’ burden and companion time. Additional functions that link other people with the people living with dementia remotely through web-based platforms can better involve more family members or friends in reminiscence, which also helps reduce caregiving burden. However, as the hardware and the activity need to be set up and a facilitator is often required during the process, the reminiscence intervention may instead become an additional burden to caregivers, especially those serving in institutional care facilities where a nursing staff member provides care to multiple people.

In the previous section, we outlined the timeline for the different technical aids used in reminiscence interventions. Since the mid-2010s, VR has gradually become a viable option for facilitating the recall of past experiences in older adults. This evolution began with nonimmersive VR [21,27,63], displaying the virtual world through an electronic screen such as a tablet, television, or computer screen. Semi-immersive VR emerged later as another option [23,24], offering a more realistic experience by using multiple large screens or a VR Cave Automatic Virtual Environment that forms an enclosed or semienclosed environment in which to display VR content. FIVR has been considered more effective in evoking memories and is therefore more favorable for reminiscence compared with other aids, because of its fully immersive features. However, this assumption was not fully supported by evidence from the selected studies. It was noted that the results were mixed when comparing FIVR with other technical aids. For example, Saredakis et al [57] and Xu and Wang [59] found that participants preferred using FIVR for visual content over a flat screen or printed photos, whereas participants in another study reported that FIVR did not provide richer reminiscence experiences than those from an iPad [47]. In addition, FIVR may present some challenges for the participant or caregiver in controlling and manipulating the technology [58]. Nevertheless, FIVR is a relatively new technology and its application in reminiscence interventions is still in its infancy. Therefore, it may be too soon to conclude that FIVR is superior or inferior to the other traditional aids. The suitability of using FIVR may depend on the type of reminiscence intervention, content of the visual stimuli, and specific person in the session.

Most of the selected studies focused on individuals with mild cognitive impairments or people living with dementia, making their results applicable to these groups. Only 1 study compared the FIVR effects between the population with mild cognitive impairment and that living with dementia [52]. The results indicated that people living with dementia were more immersed in VR, possibly because the realistic environment captured their attention better than it did for those with mild cognitive impairment. This is important because a higher level of immersion may lead to more emotional engagement, which would trigger unpleasant memories or emotions, resulting in adverse outcomes. Moreover, individuals with mild cognitive impairments displayed greater kinetic engagement during FIVR sessions, potentially owing to better physical health and mobility. However, the exact reasons remain unclear. Notably, there’s a scarcity of studies comparing patients with mild cognitive impairments or dementia with noncognitively impaired groups. Further research comparing multiple user groups, such as young adults, healthy older adults, patients with mild cognitive impairments, and people living with dementia, is essential.

Only 1 study specified its intervention type as semistructured simple reminiscence. The other 2 types of reminiscence, life review and life story review, were not examined in the selected studies. Our speculations are as follows: (1) life review and life story review require professionally trained staff, posing challenges for research teams; (2) these approaches might demand more time (≥45 min), and using VR goggles for over 20 minutes could induce negative side effects; and (3) most research teams were led by design or computer science professionals, focusing on developing and testing the FIVR prototype. Life review and life story review are vital for end-of-life care, particularly for patients with cancer [15]. Consequently, further research on FIVR-supported life review is critical to address this gap.

The limitations of this literature review are related to the characteristics of the studies and the nature of the scoping review. As noted earlier, the selected studies had some common limitations. First, the sample sizes were relatively small, ranging from 2 to 43 participants (mean 17). Only 4 studies had 20 or more participants. A small sample size has been a common issue in studies involving older adults with cognitive impairment, possibly because of the difficulties in recruitment and retention. Second, most studies were quasi-experiments, case studies, or qualitative research. Only 2 studies used control groups. Third, most studies evaluated the short-term but not the long-term effects of the interventions. Fourth, because most of the studies were conducted by the teams that created the FIVR tools, the study foci were largely on usability aspects but not on health outcomes, although these were also measured.

We attempted to identify related articles through different databases; however, the number of included studies was small (N=11). Possible reasons were that FIVR was a relatively new technology that took some time to be developed and evaluated in this field and that some studies may have been published in non–English language journals. Furthermore, there may have been publication bias; studies that did not find any significant results may not have been published. In addition, the selected studies used various research designs, sample sizes, and measurements, which presented challenges for a systematic, rigorous review, or meta-analysis.

The growing number of older adults living with dementia or mild cognitive impairments has amplified the crises of caregiver shortage and continuously rising health care costs. We reviewed existing empirical studies that evaluated FIVR reminiscence interventions. The results indicated that such interventions, if delivered appropriately, may help improve the user’s psychological and mental health and potentially decrease the burden on caregivers. The studies also revealed a positive experience with FIVR technology, which most participants found acceptable and enjoyable. On the basis of the literature review, we identified directions for future research and provided recommendations for practice in FIVR reminiscence interventions.