According to the World Health Organization (WHO) statistics, there were 1 billion people aged ≥60 years in 2020, and this number is projected to reach 1.4 billion by 2030 and double to 2.1 billion by 2050 [1]. The shift in population demographics has substantially contributed to the rising demand for and cost of medical care [2], but many older people are still facing inadequate access to appropriate, affordable, and high-quality health care. In a 2010 survey across 32 countries in Africa, Asia, Eastern Europe, Western Europe, and the Caribbean, 63% of the 1265 respondents aged ≥60 years reported that access to health care when required was a challenge [3].

Telehealth, the delivery and facilitation of health and health-related services including medical care, provider and patient education, health information services, and self-care via telecommunications and digital communication technologies [4], is one of the many new possibilities that made health care more accessible and has been widely believed to bring various benefits in aging care settings. First, it can expand health services by removing geographic and time boundaries [5] and enabling socially isolated and physically homebound individuals access to a wider range of care options [6]. Second, it can minimize the risk of direct transmission of infectious agents from person to person [7], especially during the recent COVID-19 pandemic [8]. Third, it redefines health care by engaging the patients’ familiar settings, so that both the patients and the health care providers can put greater emphasis on the intervention itself, which in turn results in improved efficiency and quality of care [9]. Furthermore, as hospitals and medical providers are under increasing pressure to provide quality care at lower costs, telehealth has been accepted and successful across a variety of medical specialties and settings [9], such as dentistry [10], psychiatry [11], dermatology [12], and COVID-19 consultation [13].

The impacts of different telehealth interventions in terms of their effectiveness, cost, and acceptability were studied; however, the results were not consistent [14-16]. For instance, a systematic review of reviews by Ekeland et al [14] in 2010 showed that 21 of the 80 included reviews concluded the effectiveness of telemedicine, 18 found incomplete evidence, the remaining 41 reviews found limited and inconsistent evidence, and the costs of these interventions were not well understood. In 2021, Snoswell et al [16] revisited the meta-analyses from 2010 to 2019 and discovered that telehealth across a range of modalities could be clinically equivalent or more effective than usual care in cardiovascular disease, dermatology, endocrinology, neurology, nephrology, obstetrics, ophthalmology, psychiatry and psychology, pulmonary, and multidisciplinary care. In the same year, Goharinejad et al [15] conducted a review of systematic reviews in the field of telemedicine, in which the 191 included reviews covering different telehealth modalities (eg, telemedicine, telerehabilitation, tele-diabetes, telecardiology, home telecare, telepsychiatry, teledermatology, and teleneurology) and outcomes (eg, clinical outcomes, cost-effectiveness, and user satisfactions) revealed inconsistent evidence regarding the effectiveness (101 positive, 22 unclear, and 1 negative), cost benefits (42 positive and 20 unclear), and satisfaction (47 positive and 9 unclear). In view of the lack of synthesized evidence, particularly in aging care, and the increased demand for telehealth services since the COVID-19 pandemic [17], we would like to extend the literature by including the latest evidence and focusing on the applications of telehealth for the older population.

A scoping review generally aims to identify and map the evidence available on a certain topic [18-20]. It is an ideal tool for indicating the volume of literature available and provides a general or detailed overview of the topic’s focus [20]; identifying gaps in the research bases; and evaluating future research priorities in a formal, systematic, and transparent manner [21]. Considering the high heterogeneity of telehealth interventions, we sought to conduct this scoping review to identify the domains in which there is evidence for telehealth’s feasibility, effectiveness, cost benefits, and acceptability in the context of aging care; discover gaps in the literature; and determine the priorities for future research.

This scoping review of systematic reviews was guided by the methodological framework of the Joanna Briggs Institute [22]. The study selection followed the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) flow diagram, and the reporting and mapping of the body of literature followed the PRISMA-ScR (Preferred Reporting Items for Systematic Review and Meta-Analyses extension for Scoping Reviews) guidelines [23]. The review protocol was registered in the Open Science Framework [24].

The eligibility criteria were established a priori [22]. We included different types of systematic reviews (eg, rapid reviews, narrative reviews, integrative reviews, systematic literature reviews, and systematic reviews with meta-analysis) that analyzed telehealth interventions involving older users or subgroup analysis of older users with or without known health conditions, including those residing in hospitals, nursing homes, and their homes. The intervention could be any form or subgroup analysis of telehealth intervention involving direct communication between older adults and health care providers. No restrictions were placed on the date and location of publications for this review. Only full-text reviews in English were included, considering the language proficiency of the reviewers, to ensure the quality of study selection and data extraction.

The systematic reviews were excluded if (1) the population did not consist of older adults or the reviews did not perform a subgroup analysis of older adults; (2) the reviews solely focused on the design or algorithm of telehealth interventions, policies, or experts’ opinions; (3) the reviews included a broader range of digital health or eHealth interventions but did not present a subgroup analysis of telehealth interventions; (4) the language was not in English; or (5) full texts were not accessible.

Figure 1 illustrates the preferred reporting items for the PRISMA flowchart of the study selection process. The initial database search conducted on September 16, 2021, identified 9700 articles, and 6198 (63.9%) were included in the title and abstract screening stage after 3502 (36.1%) duplicates were removed. In the full-text screening, 1257 articles were assessed for eligibility, and 17 systematic reviews were found to be relevant, including 1 post hoc subanalysis of a previously published large Cochrane systematic review with meta-analysis [29]. We performed another updated search on April 28, 2022, in the same databases as well as the first 10 pages of the Google search and identified another 12 relevant systematic reviews. As a result, 29 systematic reviews were included for data extraction in this scoping review.

The characteristics of the included studies are summarized in Multimedia Appendix 2 [30-61].

Of the 29 reviews, 2 (7%) were published before 2010 [62,63], 15 (52%) were published between 2010 and 2019 [29,64-77], and 12 (41%) were published between 2020 and April 2022 [78-89]. A total of 19 reviews provided details on the locations of the included studies [63,68-78,80,81,83,84,86,88,89], with the most prevalent being in North America (the United States and Canada) [63,68-77,80,83,86,88,89], Europe (the United Kingdom, France, Italy, Sweden, the Netherlands, etc) [63,68-71,73-78,80,83,86,88,89], and Australia [68-71,77,78,80,81,86].

The majority of the reviews were narrative, except for 4 that included a meta-analysis [65,74,84,86]. Among the remaining 25 narrative reviews, 5 explained that a meta-analysis was not carried out given the heterogeneity of design, participants, and intervention types [63]; data reporting with the variability of methodology in the studies [67,81]; low quality of the included articles [68]; and high selection and publication bias [78].

A total of 24 reviews presented either a conceptual definition (a working definition in terms of its abstract concept [90,91]) or an operational definition (specific process, events, or activities that the researcher used in the measurement to determine the concept [92]) of at least 1 of the 15 terminologies used (ie, telehealth, telemedicine, telecare, structured telephone, telepsychiatry, remote patient monitoring, teledentistry, telemonitoring, health information technology, remote care programs, telephone only support, remote activity monitoring, telenursing, decision support systems, and health coaching systems), and a summary table can be found in Multimedia Appendix 3.

Outcomes of interest in this review included the effectiveness in individual outcomes (clinical benefits, health literacy, and behavioral outcomes) and system outcomes (efficacy and impact on health system use), feasibility and cost benefits of telehealth interventions or programs, and older people’s acceptance of telehealth with factors affecting their telehealth use.

Most of the included reviews reported that the literature did not meet orthodox quality standards because of the study design in the lower tiers of the hierarchy of evidence [63,69,71,72,79,81]; small sample size [63,65,68,69,71,82,86]; short follow-up period [63]; small number of studies [63,65,66,68,79,81,84]; high risk of bias [67,71,72,74,84]; high heterogeneity of interventions and outcomes [64,67,69,78,81,86,87]; insufficient and partly inadequate reporting of predefined outcome values and few participants, especially in the intervention group [72]; and inconsistent measurement of the outcomes [67,69,87]. The included studies of all the reviews were conducted in a limited number of locations (Multimedia Appendix 2), and the interventions used different telehealth modalities in different settings; hence, generalizability was attenuated [64,68,75,81], and the findings might not be generalizable to the entire older population group.

This scoping review synthesized the evidence from past research on telehealth in aging care and summarized the findings of 29 systematic reviews regarding telehealth interventions in aging care. Although telehealth has garnered attention since before 2010, it was in the spotlight during the COVID-19 pandemic when >40% of the included reviews were published. The present evidence shows promising evidence regarding the feasibility, costs, and acceptability of telehealth for screening, diagnosing, supporting, and consulting in aging care. However, some discrepancies were observed because of differences in telehealth modalities, health conditions, definitions of outcomes and measurements, and costing models. In addition, we summarized and categorized various factors affecting older people’s telehealth use into individual, interpersonal, technological, system, and policy levels to provide a pathway for collaborative efforts to better prepare the older population for digital inclusion.

A large proportion of the evidence focused on curative and rehabilitative care (28/29, 97%), and there is scarce evidence on promotive, preventive, and palliative care, which is consistent with the scoping review in 2013 that the largest number of studies primarily focused on chronic disease management and symptom management [102]. Despite the importance of health education and promotion for the whole population, older adults have long been left out of health promotion activities until after 2001 when WHO experts declared that a healthy lifestyle should be emphasized for all ages [103]. Evidence has indicated that a healthy lifestyle, such as quitting smoking, limiting alcohol consumption, and increasing physical exercise, can help delay the development of many diseases, prevent the loss of functional capacity, improve the quality of life, and extend life expectancy [103]. Palliative care is another important public health issue as a consequence of the aging population, which focuses on improving the quality of life and dignity of people facing the end of their lives as well as the support and care of their loved ones [104]. For most patients in need of palliative care, the most preferred place of care is at home [105]. Nevertheless, some unmet in-home palliative care needs, such as the lack of communication among health care providers and patients’ uncertainty about the urgency of their problem, have also been reported [106]. Future research could investigate how telehealth can address these gaps and the role of telehealth in universal health coverage.

In comparison with usual care, different modalities of telehealth have demonstrated remarkably promising effectiveness in improving both individual outcomes and system outcomes. As Russell et al [107] stressed that it is important to ensure that telehealth is not inferior to usual care, our results support past reviews [14-16] that telehealth could be a viable alternative to traditional clinical practice in selected domains and further highlight that telehealth could be effectively used in a broad range of clinical disciplines. However, we should be cautious about possible biases in the literature that may limit the generalizability of the results. For instance, most empirical studies in the included reviews were conducted in countries with higher incomes, and older adults with chronic or aging-related conditions were excluded in some studies if they were not part of the target population. Moreover, our findings also reiterate the inconsistent quality of evidence reported in other reviews [14,108]. The included reviews were predominantly narrative (25/29, 86%), and most reported that the literature was not up to orthodox standards. The evidence base needs to be strengthened through additional studies on the top tiers of the hierarchy of evidence (eg, RCTs or cluster RCTs) with larger sample sizes, longer follow-up periods, and consistent definitions and outcome measures coupled with good reporting methodologies.

In terms of the feasibility of telehealth in aging care, we used users’ adherence and attrition as proxy measures and found mixed results, varying by different telehealth modalities and subpopulation types. Indeed, suboptimal adherence and substantial attrition are common in digital health intervention studies among the older population [109,110], and some contributing factors include personal choices, technical difficulties, physical and cognitive impairments, and concerns regarding the security of digital health interventions [110]. Low engagement continues to plague the internet-based studies [111], results in a study cohort not being representative of the demographics and disease status of the originally recruited study population [109], thereby threatening the validity of the findings [112]. Meanwhile, other factors such as referral by a clinician to the study, compensation for participation, having a clinical condition of interest in the study, and an older age [109] have been revealed to be associated with increased participation retention. Future research could further explore how older users’ adherence and retention rates could be improved to advance the current telehealth practices and how this could impact the effectiveness, costs, and acceptability of telehealth interventions.

Similar to the systematic review of reviews by Ekeland et al [14], several reviews in our study also reported promising benefits of telehealth in terms of cost, and we also observed some discrepancies in implementation cost savings and cost-effectiveness in different studies owing to heterogeneity in comparator care delivery modes [65], the complexity of health conditions [73], geographic locations [73], and cost models used [77,81]. A common obstacle in most published economic evaluations of digital health interventions is reliance on standard methodological recommendations for assessing health care technologies, but such methodological assumptions may not fully reflect the nature of digital health interventions, especially complex ones [113]. Moreover, the cost benefits of digital health interventions may vary over time as well as the degree to which users use them, making their impact more likely to be heterogeneous [113-115]. Further research could overcome these challenges by streamlining the methodologies. For example, as recommended by Gomes et al [113], researchers should carefully choose comparators, determine the scope of cost and effects to be considered, and identify the effects of the interventions with appropriate measurements as well as the cost of other resources before the economic analysis.

In contrast to other studies indicating that older adults have not been fully ready for telehealth [116,117], all our included reviews that assessed the participants’ experiences with and attitudes toward telehealth interventions have demonstrated good acceptance of telehealth among the older population. This difference might be explained by the use of different telehealth modalities in different studies as well as the prescreening process in some studies that excluded older adults who may have difficulty using telehealth. We identified a similar set of factors affecting older adults’ telehealth use as other reviews [118,119], and further categorizing these factors into individual, interpersonal, technological, system, and policy levels could assist in understanding the needs of the older population in this process and identify the potential collaborative efforts that individuals, health care providers, developers of telehealth applications, government and community organizations, and policy makers can make to prepare the older population for digital inclusion. To help older individuals cope with the cultural and psychological challenges associated with digital health technologies, training programs could be offered to both the older population and health care providers to improve their digital literacy as well as skills in interpersonal communication and rapport building. Although there is no “one-size-fits-all” solution, developers of telehealth applications could engage older people, especially those with special needs (eg, those with physical immobility, sensory change, negative affect, cognitive impairment, low digital literacy, or communication barriers), in the user-centered design, testing, and evaluation of telehealth technologies and keep their needs in mind. Health systems should be responsible for ensuring a smooth and continuous clinical workflow with telehealth, along with providing the latest guidelines and health information to health care providers and older patients. Policy makers could enhance clinical guidelines and policies to regulate the design and implementation of telehealth, address privacy concerns, bridge the digital divide, and improve the current payment models so that telehealth could be offered to users with better security, accessibility, and affordability.

We chose to conduct a scoping review to comprehensively cover a wide range of older subpopulations, telehealth interventions, outcome measures, and types of systematic reviews. Our choice of only including systematic reviews was in response to the rapid growth of telehealth studies and the heterogeneous aims of the systematic reviews of telehealth interventions in the aging care context. Nonetheless, this choice may have neglected the details of the included telehealth interventions as well as the exclusion of some pertinent studies in consideration of their methodology and design. Although we adopted a systematic approach guided by the methodological framework of the Joanna Briggs Institute [22], there might be undetected relevant systematic reviews. The inclusion of only full-text systematic reviews in English may also lead to the loss of sight of those reviews without full-text accessibility. In addition, the low number of systematic reviews with meta-analyses also limits the robustness of the conclusions that can be drawn.

In addition to the methodological limitations, we identified limitations regarding the generalizability of the results. First, most of the studies in the included reviews were conducted in North America, Europe, and Australia, which may limit the generalizability of our findings to the global telehealth market. Second, several reviews have reported that the prescreening process has excluded the older users with special needs (eg, physical immobility, sensory change, negative affect, cognitive impairment, and communication barriers); hence, the results may not be generalizable to these vulnerable groups. Third, we identified different definitions of the population (older adults), interventions (telehealth, telemedicine, and telecare), and outcome measures, which might be because of different search terms, research settings, and geographic locations. This makes it difficult to compare the feasibility, effectiveness, cost, and acceptability of the interventions. Therefore, it is important to standardize and carefully define the terminologies and assessment tools in future research to reduce bias and draw robust and reliable conclusions.

The development and implementation of telehealth have been further catalyzed by the COVID-19 pandemic, and this scoping review has identified considerable evidence of the effectiveness, feasibility, cost benefits, and acceptability of telehealth applications in aging care. Although telehealth remains in its infancy and there is a lack of high-quality studies to draw robust conclusions, mounting evidence indicates that telehealth plays an important complementary role in the care of the aging population. It is imperative for older individuals, health care providers, developers of telehealth applications, government and community organizations, and policy makers to make a collaborative effort. This could help gain deeper insights into the multifaceted needs of and challenges faced by the older populations; facilitate a user-centered approach in the design and testing of telehealth technologies; and improve the security, accessibility, and affordability by enhancing the existing clinical guidelines and regulations. More high-quality studies are also required to provide a robust evidence base for aging care.