The role of telehealth during COVID-19 outbreak: a systematic review based on current evidence

Background The outbreak of coronavirus disease-19 (COVID-19) is a public health emergency of international concern. Telehealth is an effective option to fight the outbreak of COVID-19. The aim of this systematic review was to identify the role of telehealth services in preventing, diagnosing, treating, and controlling diseases during COVID-19 outbreak. Methods This systematic review was conducted through searching five databases including PubMed, Scopus, Embase, Web of Science, and Science Direct. Inclusion criteria included studies clearly defining any use of telehealth services in all aspects of health care during COVID-19 outbreak, published from December 31, 2019, written in English language and published in peer reviewed journals. Two reviewers independently assessed search results, extracted data, and assessed the quality of the included studies. Quality assessment was based on the Critical Appraisal Skills Program (CASP) checklist. Narrative synthesis was undertaken to summarize and report the findings. Results Eight studies met the inclusion out of the 142 search results. Currently, healthcare providers and patients who are self-isolating, telehealth is certainly appropriate in minimizing the risk of COVID-19 transmission. This solution has the potential to prevent any sort of direct physical contact, provide continuous care to the community, and finally reduce morbidity and mortality in COVID-19 outbreak. Conclusions The use of telehealth improves the provision of health services. Therefore, telehealth should be an important tool in caring services while keeping patients and health providers safe during COVID-19 outbreak.

that is made possible by the reduction of person-toperson contact [7,8].
To reduce transmission, travel restrictions have been appointed and enforced around the world, and most cities have been quarantined [9]. However, people who are not infected with the COVID-19, especially those who are at greater risk of developing the disease (e.g. Elderly people and those with underlying diseases), should receive daily care without the risk of exposure to other patients in the hospital [7]. Moreover, under strict infection control, unnecessary personnel such as clinical psychiatrists strongly refuse to enter COVID-19 patient's ward [10,11]. Natural disasters and epidemics pose many challenges in providing health care [12]. As a result, unique and innovative solutions are needed to address both the critical needs of patients with COVID-19 and other people who need healthcare service. In this respect, technological advances provide new options [13]. Although the ultimate solution for COVID-19 will be multifaceted, it is one of the effective ways to use existing technologies to facilitate optimal service delivery while minimizing the hazard of direct person-to-person exposure [7,14]. The use of telemedicine at the time of epidemic conditions (COVID-19 pandemic) has the potential to improve research of epidemiological, control of disease and management of clinical case [7,14,15].
The use of telehealth technology is a twenty-first century approach that is both patient-centered and protects patients, physicians, as well as others [16,17]. Telehealth is the delivery of health care services by health care professionals, where distance is a critical factor, through using information and communication technologies (ICT) for the exchange of valid and correct information [18]. Telehealth services are renderdusing real-time or store-and-forward techniques [19]. With the rapid evolution and downsizing of portable electronics, most families have at least one device of digital, such as smartphones [20] and webcams that provide communication between patient and healthcare provider [21]. Video conferencing and similar television systems are also used to provide health care programs for people who are hospitalized or in quarantine to reduce the risk of exposure to others and employees [7]. Physicians who are in quarantine can employ these services to take care of their patients remotely [8,22]. In addition, covering multiple sites with a tele-physician can address some of the challenges of the workforce [8,23].
There are various benefits in using technology of telehealth, especially in non-emergency / routine care and in cases where services do not require direct patientprovider interaction, such as providing psychological services [24]. Remote care reduces the use of resources in health centers, improves access to care, while minimizing the risk of direct transmission of the infectious agent from person to person [25]. In addition to being beneficial in keeping people safe, including the general public, patients and health workers, another important advantage is providing widely access to care givers [12].. Therefore, this technology is an attractive, effectual and affordable option [14,26,27]. Patients are eager to use telehealth, but hindrances still exist [28,29]. The barriers of implementing these programs also largely depend on accreditation, payments systems, and insurance [8]. Furthermore, some physicians are concerned about technical and clinical quality, safety, privacy, and accountability [23,30].
Telehealth can become a basic need for the general population, health care providers, and patients with COVID-19, especially when people are in quarantine, enabling patients in real time through contact with health care provider for advice on their health problems. Thus, the aim of this review was to identify and systematically review the role of telehealth services in preventing, diagnosing, treating, and controlling diseases during COVID-19 outbreak.

Study design
This systematic review was conducted based on the preferred reporting items for systematic reviews and metaanalyses (PRISMA) guidelines. A method of systematic review was selected to permit a robust and reproducible approach to structure a critical synthesis of the existing and current evidence. Considering the necessity of the matter and limited available evidence on the topic, we did not register the protocol of this systematic review. Manual search in web-based resources was accomplished on Google, Google Scholar, journals which published key articles and through searching specific website (WHO, https://www.who.int, Centers for Disease Control and Prevention, https://www.cdc.gov, National Institute for Health and Clinical Excellence, https://www. nice.org.uk, National Health Commission of the People's Republic of China http://www.nhc.gov and National Administration of Traditional Chinese Medicine http:// www.satcm.gov.cn). In addition, we reviewed the selected articles references in order to identify additional studies or reports not retrieved by the preliminary searches (reference by reference).

Eligibility criteria
All studies with evidence reporting the role of telehealth services in COVID-19 were included in our analyses. In fact, studies were included if they obviously defined function type of telehealth in prevention, diagnosis, management and treatment of COVID-19, published from December 31, 2019 to April 3, 2020, were written in language of English and published in peer reviewed journals. The reason for electing December 31 was due to the fact that this date coincides with the appearance of COVID-19 in Wuhan, Hubei Province, China. Actually, all studies representing any sorts of using tools of telehealth in all aspects of health care (primary, secondary or tertiary level health care) to provide clinical services, diagnosis, assessment of symptoms, triage of patients, consultation services, and training or supervision of clinicians were included. Studies about other technologies (e.g. Internet of Medical Things or IoMT), duplicate publications, review articles, opinion articles, and letters not rendering principal data were excluded, as well as studies reporting incomplete information.

Study selection and data extraction
Two authors (A.H. and E.M.) who performed the literature search also independently followed the application of the inclusion and exclusion criteria and screened the studies based on the titles and abstracts. After initial screening, full-text of studies were obtained and examined to ensure eligibility for the development of the data extraction table.
Data were extracted from all papers which met the eligibility and inclusion criteria for the review. The following data were extracted and analyzed: first author, date of publication, country, design of study, type of used telehealth, key outputs of studies and effects of telehealth.

Quality assessment
To assess the quality of the included studies, the Critical Appraisal Skills Program (CASP) checklists were accorded. To teach people how to critically appraise different types of evidence, the CASP tools were developed [31]. Included studies were divided into three categories of poor, medium, and good for scoring the quality of them.

Evidence synthesis
For expressing and synthesizing the results of the included studies, narrative synthesis of overall evidence was undertaken by comparing and contrasting the data. Three stages of the narrative synthesis included the development of a preliminary synthesis, exploration of the relationships within and between studies and the determination of the robustness of the synthesis [32]. Data of the included studies was qualitatively described and presented. The authors to reach consensus on the findings, met frequently to discuss.

Search results
The details on the literature search and processes of screening are illustrate in Fig. 1. Following the removal of duplicate search records and screening titles and abstracts of studies, we appraised 46 relevant studies in full text. From the studies of remaining, 39 articles did not meet our inclusion criteria and were removed. Finally, one study was added after reference screening (reference by reference) and eight full studies included for stage of evidence synthesis.

Characteristics of the included studies
Some general characteristics of the included studies were demonstrated in Table 1. The included studies published in various international journals between February 17, 2020 and Apr 9, 2020 were mostly conducted in the USA. Eight included studies were carried out in six countries: USA (n = 5), China (n = 2), UK (n = 2), Canada (n = 2), Iran (n = 1) and Italy (n = 1). Based on the design of study, five studies were cross-sectional, two were case studies and one was case-control. In the included studies, most of telehealth and social media channels were applied during COVID-19 pandemic such as telephone, live video conferencing, and e-mail.

Quality assessment
Our systematic review included eight studies that were appraised using the tools of CASP. The qualities of the assessed studies were generally in high level. Six (75%) studies enjoyed good quality, and two (25%) had medium quality. Also, no studies were excluded on the basis of the level of quality appraisal.

Telehealth services during the COVID-19 outbreak
We recognized eight studies that presented precious data on telehealth regarding the status of people infected with COVID-19. Telehealth has the capability to incorporate several organizations and situations of health care into one virtual network, led by the central clinic. This network can contain physical locations in different region: central and remote clinics, prevention centers, private clinics, and, private offices of physicians, centers of rehab state and all registered patients within their locations. By using virtual care for very regular, essential medical care, and deferring elective procedures or yearly checkups, we can free up medical staff and equipment required for those who become seriously ill from COVID-19. Additionally, by not congregating in small spaces like waiting rooms, the ability of the coronavirus to transmission from one person to another were thwart.
Keeping people discrete is called "social distancing". Keeping healthcare staffs discrete from patients and other providers is "medical distancing". In present time the Telehealth is one strategy to help us carry out this.
Telehealth can mobilize all aspects of healthcare potentials to decrease transmission of disease, conduct people to the right level of health care, ensure safety for provide health services online, protect patients, clinicians, and the community from exposure to infection, and finally diminish the burden on the healthcare providers and health system. Some of the telehealth usage cases for patients were control and triage during the outbreak of COVID-19 pandemic, self and distance monitoring, treatment, patients after discharge in health centers (follow-ups) and implementation of online health services. These methods have the potential to reduce morbidity and mortality during pandemic. For all healthcare workers and clinicians with mild symptoms can still work remotely with patients, facilitate quick access to medical decision making, seek second opinion for severe cases of patients, exchange cross-border experiences, and offer teleradiology and online trainings for health workers. To provide continued access to necessary health services, telehealth should be a key weapon in the fight against the COVID-19outbreak.

Discussion
The aim of this systematic review was to identify the role of telehealth services in preventing, diagnosing, treating, and controlling diseases during COVID-19 pandemic. In this review, we explained the benefits and implications of several tools of telehealth with the purpose of improving the management of COVID-19 infection. Nowadays, the best preventive strategy is to avoid being exposed to the coronavirus, because there is no vaccine to overcome COVID-19 in the all countries [41]. A series of strategies have been proposed for infection prevention and control (IPC) that may diminish the exposure risk, such as wearing of face masks in mass population, Covering mouth and nose with tissue when coughing and sneezing, continuous hand washing with soap and water or hand sanitizer containing at least 60% alcohol, avoidance of close contact with others and keeping true social distance, and refraining from touch of unwashed hands with eyes, nose, and mouth [42]. Meanwhile, to reduce the number of those who receive face-to-face services of health care, healthcare workers can contact with patients through telecommunication tools for triaging, assessing and caring for all patients [43]. Telehealth with use of live video conferencing or a simple mobile call allow health care professionals to ask special questions and collect required information, triage of patient and supply consultation, or if a person can continue to self-monitor symptoms at home while recovering. It can also be applied for regular check-ins such as respiratory, blood pressure and oxygen level rate needed in home [34].
During the COVID-19 outbreak in China, online mental health surveys with communication programs, such as Weibo, WeChat and TikTok have enabled mental health professionals and health authorities to render safety mental health services online during the COVID-19 pandemic [44]. Chinese government officials launched a remote consultation network that can be carried out internet or telephone consultations in a safe setting to ensure the continuous provision of mental health services and reduce the hazard of cross infections [45]. Also, the National Health Commission of China have published several online guideline and free electronic books about COVID-19 with the aim of helping the progress of Chinese people emergency interventions, safety, improving the quality and effectiveness of emergency interventions [10]. In addition, telehealth can provide mental online health services in the setting of patient isolation by reducing the mental health burden from COVID-19 and sharing information about symptoms of burnout, depression, and anxiety [14].
Greenhawt et al. suggested that telehealth has several benefits in providing allergy and immunology services such as limiting exposure of health professionals to potentially infected patients and access to the rapid evaluation for COVID-19 infection [38]. in addition to the conventional methods used in diagnosing COVID-19, the study identified a novel screening and triage strategy during deadly COVID-19 pandemic in Iran. Services for teleradiology and teleconsultation for triage of COVID-19 infection through a social media massager delivered by Iranian Society of Radiology (ISR) to response to the shortage of on-site thoracic radiologists during COVID-19 pandemic [33]. In addition to taking actions to protect the health and safety of patients, also staff should take mobile health technology to develop staffing plans and carry out billing for healthcare services [39].
Our results demonstrate that to manage COVID-19, there are many easy-to-set-up potentials in live video consulting. Live video conferencing can lead to the avoiding of direct physical contact, thereby diminishing the risk of exposure to respiratory secretions and preventing the potential transmission of infection to physicians and other healthcare providers [34]. Also, live video could be very useful for patients seeking consultation on covid-19, for people with heightened anxiety and instead of in-person visits in cases of chronic disease reviews (such as diabetes and cancer), some medication checks, and triage when telephone is insufficient [23]. In order to control the spread of the COVID-19 outbreak, video consultations and telephone follow-up is possible in multiple cancer settings including lung, endometrial, colorectal, and prostate [37].
Based on the study conducted in the USA, phone calls and electronic health records (EHR) can facilitates screening or treating a patient without the need for inperson visits and improve decision making process among healthcare team in an ambulatory and urgent care [35]. Generally, the impact of telehealth during the COVID-19 pandemic in preventing morbidity and avoiding of presence the public from high-risk areas such as hospital premises was significant. Also, the elderly people can access health services by using electronic devices [36]. These days, suitable adaptation of local systems with changes regarding to payment and coordination of services are major barriers for the largescale use of telehealth to deal with COVID-19 infection [8]. Finally, we hope can make substantial progress in preventing and controlling COVID-19 pandemic through further training of health providers and patients on how to make the most of telehealth tools, revisiting traditional definitions of clinical practice and using closed online platforms.

Future research
The biggest challenge for future research in the use of telehealth is probably defining the obstacles and facilitators in health providers and patients. Future research is suggested to specify the effects of telehealth solutions in the efficiency indicators and hospital performance. Also, further global research is warranted to determine how to set up telehealth in primary care. Researchers can also examine the effectiveness of using telehealth approaches in different health areas, especially in the field of home nursing the elderly who are high-risk people in the community. It is also highly recommended to use this technology in the field of psychiatry as it does not require in-person visits. Other future research can tap into evaluating the satisfaction of patients and providers with telehealth services.

Limitations
Our systematic review holds three limitations. Firstly, it is possible that some relevant studies were not taken into account because they have been published in languages other than English (e.g. Chinese). Secondly, we did not have access to some other databases such as CINAHL and PsycINFO. Thirdly, there could be some other studies on this theme in the literature that skipped our attention and analyses though we did our best to adopt a comprehensive search strategy and cover a broad range of evidence across the world.

Conclusion
This study provides a comprehensive systematic review solely exploring the potentials of telehealth during the COVID-19 pandemic. In response to WHO's call for studies on the COVID-19 infection and presentation of the most recent evidence published in this early period of the outbreak for health care providers, this study was conducted to identify the role of telehealth during COVID-19 outbreak. As the COVID-19 epidemic scales exponentially across the worlds, calls for expended use of telehealth as innovative solutions, clearly highlight unmet needs in the world healthcare system. Telehealth has the potential to address many of the key challenges in providing health services during the outbreak of COVID-19. Also, telehealth can help us avoid direct physical contact and minimize the risk of COVID transmission and finally provide continuous care to the community. Based on the findings of this review study, clinicians and patients are strongly recommended to apply telehealth tools as an appropriate option to prevent and contain COVID-19 infection.