Dose of Telehealth to Improve Community-Based Care for Adults Living with Multiple Chronic Conditions: A Systematic Review

The purpose of this systematic review is to identify evidence of the appropriate dose of telehealth intervention services provided to community dwelling adults experiencing chronic illness or disability related to effectiveness, quality, safety, and cost. Academic Search Complete, CINAHL, MEDLINE, Cochrane, and JBI were searched using combinations of “telehealth or telemedicine or telemonitoring or telepractice or telenursing or telecare AND chronic illness or chronic disease”. Of the identified 449 articles, 47 articles met the inclusion criteria. Most study designs were quasi-experimental one group pre-test post-test (N = 16) with few Randomized Controlled Trials (N = 12). Twenty-three published articles studied the effect of telehealth for one chronic condition (49.9%) while 24 (51.1%) examined the effectiveness of telehealth for multiple chronic conditions. Measurement of telehealth outcomes varied and included efficacy, healthcare utilization, quality, adherence, cost, and safety. No standard measure of dose could be extrapolated. Length of intervention was measured and reported differently in each study. The dose of telehealth services that improve care effectiveness, quality, safety, and cost is still unknown for community dwelling adults experiencing chronic illness. ment at the RCT and Comparative Effectiveness level is still needed.


Introduction
Living with Multiple Chronic Conditions (MCC) increases the likelihood of premature death, disability, and cost of care [1]. Currently, six in ten adults in the United States have a chronic illness and four in ten adults have two or more chronic conditions [2]. People with MCC account for most of healthcare spending, placing them at the center of initiatives to improve health system performance [3]. However, patients who experience MCC often delay or decline care due to transportation costs to multiple visits to clinicians at different care sites, which increases the risks of errors and poor care coordination [4]. Hence, wellcoordinated, cost-effective, and safe care is critical for patients with chronic illnesses, especially those with MCC. Initiatives to improve outcomes and decrease cost for care of people with MCC often seek to alter care from intervening only after complications arise to maintaining health with an emphasis on productive healthcare teams, use of technology, access to community resources and patient engagement; known as the Chronic Care Model [5].
Users of the Chronic Care Model have long recognized the benefit of effective use of home and community-based services to improve the health of individuals wanting to live in their own homes instead of long-term care facilities [6]. Evidence shows that keeping individuals in their homes, instead of long-term care facilities, requires multiple essential components including: a knowledgeable, proactive interprofessional team; dynamic communication between caregivers, patients, healthcare system members and community resource providers; establishing mutual goals of care; tailored coordinated consistent education for both the patient and caregivers; and, use of evidence-based practice [7]. In rural areas, this level of care coordination is challenging due to social determinants of health including poor access to care due to cost, inadequate numbers of primary care providers and specialists, transportation difficulties worsened by decreased functional ability, and lack of knowledge of available community resources [8]. Thus, persons living with MCC in rural states require additional interventions to stay in their communities. Telehealth has been used as a solution to deliver care to patients with MCC with limited access to healthcare, while eliminating barriers of access, distance, and transportation [9].
Telehealth, for the purposes of this article, is the provision of remote health care, directly to the patient, using a variety of technology, including telephones, smartphones, and mobile wireless devices, with or without a video connection E-Health Telecommunication Systems and Networks [10]. The most consistently published benefits of the use of telehealth interventions include increased communication with healthcare providers who provide education, counseling, or remote monitoring of chronic conditions to improve health outcomes [11]. In addition, telehealth has been shown to improve health, reduce costs, and holds promise for scalability to a larger population [12]. While the current evidence supports moving from research that investigates the effectiveness of telehealth to implementation and practice-based research, little evidence can be found related to the dose of telehealth intervention needed to improve outcomes or reduce costs [11]. Hence, there is a gap in knowledge when designing rigorous implementation projects related to the dose of telehealth intervention needed.
The purpose of this review is to identify evidence of the appropriate dose of telehealth intervention services provided to community dwelling adults experiencing chronic illness or disability related to effectiveness, quality, safety, and cost. The question being addressed is, "In community dwelling adults experiencing chronic illness or disability, what dose of telehealth services improve care effectiveness, quality, safety, and cost?".

PRISMA Methods
This review was performed and reported according to the PRISMA-P 2015 checklist [13]. The eligibility criteria for the review included the following databases: Academic Search Complete, CINAHL, MEDLINE, Cochrane, and JBI.
The MeSH Terms/Key Words used were "telehealth or telemedicine or telemonitoring or telepractice or telenursing or telecare AND chronic illness or chronic disease". The search mode chosen was "Find all search terms" and the limitations set were: Scholarly Journals, English, Human, Outpatients, All Adult. This search resulted in 449 abstracts and this initial search was replicated by 2 authors (JM, AJ). All information obtained was only from what was presented in the published article. All records were maintained using separate Endnote Libraries for included and excluded articles and an Excel database of findings that were imported into SPSS version 26.
Each of the 449 abstracts was reviewed for the following inclusion criteria: quantitative analysis of data that involved adults greater than the age of 18, at least 1 chronic illness, direct to patient telehealth services, and community dwelling participants. Exclusion for review included studies with qualitative design, only participants under age 18, or no chronic illness addressed. In addition, articles that were preliminary communications, meeting updates, conference abstracts, study protocols, case studies, obtained no outcome measures, telehealth was not the intervention, telehealth provided is not in the home (i.e., provider to provider), participants were non-community dwelling (i.e., nursing home), review articles, and technology methodology papers with no patient participants were excluded. E-Health Telecommunication Systems and Networks After the initial review of abstracts, 373 were excluded and 76 full text articles were identified as meeting the above criteria for inclusion and were retrieved for further review. Reasons for further exclusion included: no mention of telehealth, the only use of telephones was to collect study data, review article, pediatric population, editorial, for education purposes or commentary, only provider to provider communication, study protocol, surgically implanted telecommunications, technology development process evaluation, and qualitative design. Each of the 76 full-text articles was separately reviewed by 2 authors for inclusion/exclusion criteria. If the article met inclusion criteria, the article was critiqued and placed into a literature matrix developed a priori for congruence of interpretation. If a differing opinion occurred, the article was reviewed by a third author (SD or JH) for consistency and resolution. See Figure 1 for the full literature review flow chart according to PRISMA guidelines [14].
The review matrix included the authors' location, year published, study aims, design, total sample size, telehealth intervention sample size, sample description, number of chronic illnesses studied, type of chronic illness, measures, type of telehealth (Remote Patient Monitoring (RPM), asynchronous, synchronous, mixed), length/dose of intervention, results, and study limitations. The Cochrane Collaboration's tool for assessing risk of bias across studies and presented in the limitations section [15]. Since meta-analysis of the findings will not be performed, grading the body of evidence is not appropriate.

Study Description
Year published was extracted from each article and is analyzed and presented in the findings as a range and mode.
Location was normalized to the Country of the location of the interventions as well as the number of interventions occurring in each country.
Only quantitative study design studies were included. Type of trials was collected as Randomized Controlled Trial (RCT), quasi-experimental 1 group, quasi-experimental 2 group, quasi-experimental pre/post, retrospective, and descriptive is presented via mode of use. Types of trials are presented via mode of use.
The total number of intervention participants in each study and the total number of participants receiving telehealth in each intervention, the number of participants receiving telehealth across all studies, and the mean and standard deviation of telehealth participants are presented.

Participant Description
The sample description of age was collected from each article as mean age for each study. Income, where reported, was abstracted from each article in US dollars and is reported as frequencies. Education, where reported, was collected as the mode from each study and is reported as frequency. Urban or Rural, was recorded from the article when reported and is reported as frequency. Race of participants was abstracted from each article when available as percentage of non-white participants. Gender of participants was recorded when available in each article and is reported as percent male and female.
Chronic illness number and type were collected from each article. If an article included multiple chronic conditions, each individual condition was noted and included as both an individual chronic condition and as MCC. Number of chronic illness described in each article was recorded as a continuous variable and is reported using mean and standard deviation. Types of chronic illness are reported as frequencies.

Study Measures
Study measures were normalized into types of measures and included adherence, cost, efficacy, healthcare utilization, quality, and safety are reported as frequencies.
The type of telehealth services evaluated in each study is reported as frequencies. The type of telehealth offered was normalized into the three major types of telehealth, synchronous, asynchronous, and remote patient monitoring (RPM).
Due to differing ways dose was collected in each study, the dose of intervention collected from each article was transformed into weeks, and is reported in range, mean, and standard deviation.

Study Results & Limitations
The results of each study were reviewed. If the aims of the study were reached E-Health Telecommunication Systems and Networks the results were recorded as positive. If the aims of the study were not achieved, the results were recorded as negative. If no change was found between telehealth and usual care, the results were recorded as neutral. If the aims of the study were partially met, or not fully achieved, the findings were recorded as mixed. All results are reported in frequencies. The limitations for each study will be presented in a table.
The relationship between dose, type of telehealth intervention, and results (positive, negative, mixed, and neutral) was examined. Differences between types of chronic illness and telehealth and dose (in weeks) were assessed using analysis of variance techniques with an alpha threshold of 0.05. All analyses were performed using SPSS version 26. The authors held no preformed assumptions of the findings. Hence, power was not calculated prior to analysis.

Results
After reviewing the 76 full-text articles, 47 articles met the inclusion criteria for this systematic review. See Table 1

Participant Description
Mean age of telehealth participants was found in 34 of the articles and ranged from 40 -83 with mean age at 66.1 (SD, 11.48). Income was reported in 7 articles. Two studies reported income as "comfortable", two studies reported income as less than $14,000 and two studies reported income between $20,000 -$40,000. The remaining study reported that 25% of the participants had an income that was "inadequate to cover bills." Eleven reported the education level of

Length of intervention was measured and reported differently in each study. E-Health Telecommunication Systems and Networks
Most articles listed the amount of time that the intervention was funded, measured, or observed. The amount of time each participant received the intervention, or the amount of time spent engaging with telehealth was not reported.
Hence, dose of intervention was normalized to weeks participants received telehealth. The weeks of telehealth evaluated in each study ranged from 0 -520 (mean of 50.2 weeks, SD, 94.7). There were no significant differences between the type of telehealth offered in a study and the mean length of time telehealth  Table 2.

Limitations
Of the 47 articles reviewed, a small number were RCT designs (N = 12). Of the RCT designs, limitations were vast. Lack of standard quality measurement across studies suggests that intervention effect estimates are inconsistent and unpredictable. Small sample sizes, short duration of the intervention, lack of fidelity to intervention, self-report survey response, convenience samples, lack of generalizability, and participants lost to follow-up lead to a high risk of bias. The quality of reporting in articles and the details of the intervention were often not described, hence replication would be difficult. A matrix table of the RCT studies can be seen in Table 3.

Discussion
In community dwelling adults experiencing chronic illness, the dose of telehealth services that improve care effectiveness, quality, safety, and cost is still unknown. Dose of intervention based on these domains of measurement cannot be determined from this review. Dose is recorded and reported inconsistently across studies. In the literature the most information is based on weeks of delivery  but not the time spent with the provider, in education, or interacting with the intervention. The findings from this systematic review do indicate that longer duration of telehealth services (51 weeks), regardless of modality, produced positive outcomes as opposed to those with shorter durations (37 -38 weeks) that produced neutral or mixed results. As the use of telehealth due to COVID-19 increases, the main problem that remains is how to best implement telehealth in existing work structures and treatment protocols. Concentrated effort on workflow issues such as dose of intervention and clinical practice standards are necessary to ensure that telehealth is being used in the most appropriate ways to improve the patient and clinician experience. Without assessing for the appropriateness of offering telehealth, patient-centered, timely, efficient, and equitable telehealth provision is not possible. The widespread international study locations found in this systematic review are a true indicator that telehealth is viewed as a global initiative to improve the care of people with MCC. Telehealth has been associated with having a positive impact on outcomes for all chronic conditions. Most frequently, telehealth was used for multiple chronic conditions using a mixed telehealth intervention; however, the studies presented in this review varied in quantitative design, me-thodology, and quality. The evidence related to telehealth has been building for over 2 decades. At this point in knowledge development, study design should be RCT and Comparative Effectiveness. Additionally, while using telehealth for rural populations has been promoted [16], only 15 of the 47 articles in this review noted the location of their intervention. Of those 15, only four were in rural areas and none were a RCT design. Hence, rigorous evaluation of the use of telehealth for rural populations is still needed, especially in regard to dose of telehealth interventions.
This systematic review highlights that demographic information about participants is collected infrequently and inconsistently. Telehealth is often proposed as a solution to decrease health disparity such as a higher burden of illness, injury, disability, or mortality experienced by those with chronic conditions. However, health care disparity such as lack of insurance, access, and quality are rarely measured in telehealth research. In addition, large amounts of missing data in relation to the determinants of health, such as access to care, were observed. The digital divide makes accessing telehealth an issue [17]. Understanding the results of telehealth trials in the context of the population will continue to be important as we attempt to diminish health disparity in the context of the determinants of health. Age, gender, income, education, rurality, and race all impact efficacy of health interventions. Understanding these demographics in relation to the effectiveness, cost, cost-effectiveness, and the patient experience are domains of measurement suggested by the National Quality Forum guidelines for telehealth [18]. These domains must be present in all telehealth work moving forward and should be evaluated in the context of the determinants of health.

Conclusion
After completion of this review, drawing generalizations about dose and impact on outcomes of care is not yet possible. Collecting and reporting data related to clinical workflow such as dose of intervention specific to disease and type of modality is recommended. In addition, focus must be placed on patient-centered, timely, efficient, and equitable care. Rigorous study design at the RCT and Comparative Effectiveness level is still needed. Future rigorous studies must use a standardized tool to measure demographic information that includes individual person factors of the determinants of health so that future interventions can impact health disparity. Developing clinical implementation knowledge for community dwelling individuals who experience MCC in relation to the effectiveness, cost, cost-effectiveness, and the patient experience will be crucial to realizing the promise and potential of telehealth.

Conflicts of Interest
The authors declare no conflicts of interest regarding the publication of this paper.