Evaluation of the triple aim of medicine in prehospital telemedicine: A systematic literature review

Abstract

Objectives

With telemedicine becoming more widely implemented in emergency situations, understanding the quality and content of current findings that explore prehospital telemedicine is vital to establish best practices and guide future research. This systematic review examines the clinical importance of telemedicine in patient-provider ambulance-based settings with a focus on multifunctional systems for general prehospital emergency populations.

Methods

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology we found 1564 abstracts, which were blind-reviewed by independent reviewers. Relevant articles were reviewed, classified, and analyzed according to research methods and technology type, as well as quality, cost, and satisfaction. The studies were also reviewed for validated evidence-based practice.

Results

Those studies that looked at cost, quality, and satisfaction with care generally shared favorable results. Setup notwithstanding, cost was comparable or less than controls. Care quality was also found to be in line with or slightly preferable to face-to-face care with some advantages in response time and quality. Patients and providers were satisfied with the systems. Common obstacles included limited bandwidth and small sample sizes.

Conclusions

Although feasibility remains salient, research regarding the impact of ambulance-based telemedicine on patients and healthcare providers is encouraging, but nascent. As a whole, this body of literature does not yet adequately speak to the most important concerns of medicine: quality, cost, and satisfaction. More research is needed in each of these areas. However, those studies that do address these matters share hopeful results. Future research should test these mechanisms in prehospital settings with greater rigor.

Keywords

Ambulance emergency medical services prehospital telemedicine

Introduction

Background

Ambulances often have lengthy travel times to emergency sites,^1-2 and upon arrival, may find non-emergency situations,³ often associated with reduced resource access, lower patient satisfaction, reduced quality of care, and rising costs for patients and providers.^4,5 Furthermore, endeavors to reduce avoidable admissions via coordinated care, continuity of care, home visits, and other similar mechanisms show insufficient evidence of reversing this trend.^6–9 One promising solution in prehospital care is ambulance-based telemedicine, which enables the transmission of patient data from an ambulance to a hospital’s emergency department (ED)¹⁰ and/or physician and may reduce unnecessary prehospital transports.¹¹ Although ambulance-based telemedicine has seen increased usage in recent years, usage rates remain low.¹²

Importance

Telemedicine is the remote use of telecommunications to provide health services and transmit clinical information about a patient between care providers or between patient and provider.^12–14 Telemedicine is driven by high demand for a particular type of healthcare service and the clinical expertise to supply it.¹⁵ Telemedicine includes transmission of patient information in three ways: synchronous (two-way data), asynchronous (store-and-forward), and remote patient monitoring.^12,16 Clinical and diagnostic information obtained from the electronic health record and similar resources serve as standardized outcome measures of telemedical care.^14,17 Telemedicine in prehospital care may include applications with real-time video¹³ to assist in assessing and treating time-sensitive conditions such as stroke and myocardial infarction.^18–20 ED treatment via telemedicine increases the number of patients treated and patient satisfaction with treatment, compared to treatment without telemedicine.²¹

The hub-and-spoke telehealth model, in which peripheral EDs connect with larger EDs, positively impacts healthcare services and patient outcomes and has been demonstrated as an effective model.⁷ Telehealth services also lower patient transfer costs in rural areas by reducing unnecessary ED transfers.^7,22 Results on cost effectiveness are mixed, with benefits for synchronous video delivery but less effectiveness for delivery of services.²³ Prehospital telemedicine has demonstrated financial benefits for condition-specific diagnoses (e.g. stroke).²⁴ However, implementing telemedicine requires adequate connectivity and rural areas often have low telemedicine adoption rates due to concerns such as signal drops and fewer resources.^13,25

Systematic reviews of satisfaction in telemedicine applications find benefits despite methodological inconsistencies.²⁶ Although telemedicine increases patient access to care²⁷ and positively impacts the triple aim of medicine,²⁸ we found no review that specifically addressed the triple aim with regard to telemedicine used in general prehospital, emergency situations. This systematic review examines the effectiveness and non-inferiority of ambulance-based telemedicine interventions,²⁹ emphasizing quality, cost, and satisfaction with multi-functional prehospital telemedicine systems built for general conditions (rather than one or two specific pathologies) – consistent with the triple aim of medicine.^27,28

Methods

This systematic review follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines^30,31 for searching, inclusion, and exclusion criteria. See Figure 1 for the PRISMA flow diagram.

Figure 1.

Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) flow diagram.

Inclusion criteria

With no date limitations, we utilized a Boolean expression to search the CINAHL, PubMed, and Web of Science databases for the following criteria in the titles or abstracts: “Paramedic” OR “Emergency” OR “Ambulance” OR “EMS” OR “EMT” AND “Telehealth” OR “Telemedicine”. We identified a total of 2592 relevant abstracts and removed 1028 duplicates.

Exclusion and inclusion criteria

For the remaining 1564 abstracts, the lead researchers developed exclusion and inclusion criteria based upon the research question. Included articles (a) used empirical designs; (b) appeared in peer-reviewed journals; (c) were available in the English language; (d) included potential transport to hospitals via ambulances equipped with telemedicine for general emergency populations (telemedically connected ambulances often capturing audio, video, vital signs, and more if needed or relevant); (e) involved pre-hospital communication between the doctors and paramedics, emergency medical technicians, or patients, which provided a rich communication medium and delivered vitals in real time; (f) were not a systematic review or meta-analysis. The abstracts were then divided roughly equally between six reviewers, with at least two independent reviewers for each article, who blindly and independently reviewed each article’s title and abstract and decided to exclude or include each article based upon the pre-determined inclusion and exclusion criteria. Once all reviews were complete, the lead researchers un-blinded the independent reviews and resolved all conflicts through consensus, using the full article if necessary, leaving 13 articles in the final synthesis.

Reporting criteria

Data extraction from remaining articles was conducted independently by the first two authors and reconciled by consensus with input from the third author. Consistent with our primary research questions, the final articles were evaluated on quality, cost, and satisfaction with care. Additionally, we reported on (1) setting; (2) research methods/purpose (e.g. study design, groups, models); (3) measures used; (4) conditions; (5) type of telemedicine used and associated challenges; and (6) reported outcomes (e.g. number and length of ambulance transports, disposition of sample and control patients, clinical or statistical significance).

We also used the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool^32–34 to assess each study’s quality based upon selection bias, study design, handling of confounders, blinding, data-collection methods, and withdrawals and dropouts. This generated a global rating of strong, moderate, or weak for each article.

Results

Results highlight descriptive features of the studies; outcomes related to quality, cost, and satisfaction with care; overall patterns of findings (Table 1); and a review of the EPHPP evaluation to rate the studies on their scientific rigor.

Table 1.

Setup and outcomes included studies.

Study	Urban vs rural	Country	Study type	Intervention population	# of successful missions	Average mission travel time (min)	Average cost savings per visit	Quality (care vs system)	Satisfaction
Bergrath et al., 2011	NR	Germany	Observational	Patients: NRPhysicians: 2Paramedics: 10	157	NR	NR	System	PhysiciansParamedics
Bergrath et al., 2013	Both	Germany	Observational	Patients: 35Physicians: 9Paramedics: NR	35	24.9	NR	System	NR
Brokmann et al., 2016	Both	Germany	Controlled	Patients: 80	426	NR	NR	Care	NR
Cabrera et al., 2002	Urban	Spain	Controlled	Patients: 100	101	131.9	€60.30	NR	PhysiciansParamedics
Cho et al., 2015	Urban	Korea	Controlled	Patients: 82Physicians: 52	41	NR	NR	System	NR
Curry and Harrop, 1998	Urban	UK	Report	Patients: 42	NR	NR	NR	System	NR
Felzen et al., 2017	Urban	Germany	Controlled	NR	539	NR	NR	System	NR
Kwak et al., 2009	Urban	Korea	Pilot/ Feasibility	Paramedics: 14Physicians: 5	55	NR	NR	System	NR
Langabeer et al., 2016	Urban	US	Controlled	Patients: 5570	5570	39	NR	Care	Patient
Langabeer et al., 2017^a	Urban	US	Controlled	Patients: 5570	5570	39	ED: $2468.00EMS: $103.00	NR	NR
Mandellos et al., 2004	NR^b	Greece	Pilot/ Feasibility	Patients: 20	20	20	NR	System	NR
Pavlopoulos et al., 1998	NR	Sweden, Greece,Italy, Cyprus	Pilot/ Feasibility	Patients: 400	400	Sweden: 25Greece: 35Italy: NRCypress: NR	NR	NR	NR
Yperzeele et al., 2014	Urban	Belgium	Pilot/ Feasibility	Patients: 41	41	36	NR	Care	ParamedicsNurse

NR: not reported.

^aBoth studies by Langabeer and colleagues utilize the same dataset.

^bAuthors indicate that the study took place in the region of Rion, Greece, but do not specify if that is considered rural or urban in that country at the time the data was collected.

Setting

In total, 10 articles report findings from urban locations – two of these also reported findings from rural locations^32,34 and three articles did not specify the setting.^35,36,37 In the two studies where rurality is mentioned, one mentions only that rural areas were included³⁴ and the other reported that 13 of 35 included emergency missions involve rural areas.³² Both of these studies were conducted in Germany. Geographically, the studies occurred in a variety of locations, including Germany,^38–40 Spain,⁴¹ Belgium,⁴² Greece,^35,36 the United Kingdom,⁴³ Korea,^44,45 and the United States.^11,46

Type of study

Four articles used retrospective data.^39–41,44 Two measured the influence of telemedicine use on pre-hospital evaluation and treatment of patients.^40,44 Three articles utilized feasibility studies to assess effects and possibility of telemedicine usage in ambulances,^35,42,45 and two of these specifically tested the reliability of in-ambulance telemedicine.^35,42 Four used observational studies to demonstrate the impact of the use of telemedicine in ambulance transportation. One final study conducted a cost-benefit analysis of the use of telemedicine in emergency medical services.⁴⁶

Study (and, as applicable, control) population characteristics

All articles used non-randomized populations. For sample and control groups, five^{11,42,44,46,47} reported gender and age, two of which also reported race.^11,46 Five others did not report any of these.^{35,36,39,43,45} Of the remaining three, one reported age and clinical experience of the EMS physicians,³⁷ another reported the type of resource used (general practitioner, advanced life support, or basic life support),⁴¹ and the last³⁸ collected gender and age for all sample subjects but only reported gender and age for the three subjects who were discussed as case studies.

Measures and conditions

Measures were not consistent, but a small majority included telehealth reliability.^{35,36,39,41,42,44,45} Telehealth cost^41,46 and prehospital symptoms^38,42 were among the more practical measures for this review. The remaining articles used relatively disparate research measures – many related to feasibility. Only four articles^38,39,40,42 reported the conditions associated with the request for help (e.g. stomach pain, trauma, cardiac distress, etc.). Several reported prehospital diagnoses,^38,39,42 one reported the top three chief complaints,¹¹ and two reported the medical severity score.^37,39 One reported the pre-hospital Glasgow coma score.⁴² The remaining two reported trauma type, pain rating, vital signs,⁴⁷ level of consciousness and type of situation (disease, trauma, etc.).⁴⁴

Technology and equipment used

Overall, 11 articles reported teleconsultation as part of the telemedical program. Two⁴¹ transmitted still images only, not video; however, one transmitted audio and may have had one-way video, although it was unclear in the article.⁴¹ All but two included electronic transmission of patients’ vital signs from the EMS personnel to the receiving (remote) physician/emergency department.^43,45 Other studies used global positioning system,^33,46 remote electronic medical record system access,¹¹ an identification card reader,⁴² and a device that influenced traffic signals.⁴¹ See Figure 2 for frequency of each technology used.

Figure 2.

Equipment usage by study.

Cost of care

Two articles compared costs of telemedical care with traditional care.^41,46 The first evaluated costs of ambulance care and discovered telemedical care saved €6030 on average per run when compared to the traditional model.⁴¹ The other study examining costs found statistically significant average savings in transport with telemedically enabled ambulances: $103 less per patient compared with a control traditional care group and a 6.7% reduction in ED visits (a savings of $2468 per visit, on average).⁴⁶

Quality of care

Only two studies discussed quality of medical care as a variable in any detail.^40,42 In the first study to discuss quality of care in detail, in-ambulance diagnoses were compared to in-hospital diagnoses and correlated positively across a variety of conditions (stroke, other neurological disease, trauma, etc.), although the sample size (n=41) was relatively small.⁴² In the other study, 80 telemedical encounters involving pain reduction were compared with similar historical cases that did not involve telemedicine, and overall, quality of pain assessment was superior in the telemedicine encounters.⁴⁰ A third study noted that there were no fatalities in conjunction with their research.¹¹ Finally, although not a direct measure of clinical improvement, a fourth study found no significant difference between the telemedical and phone conditions in the ability of physicians to form a diagnosis. However, this same study did cite challenges related to bandwidth and their specific equipment interfering with data transmission.⁴⁴

Satisfaction with care

One study specifically reported on patient satisfaction from follow-up phone calls (with and without telemedicine) and found no statistical difference between the two types of encounters,¹¹ whereas two others noted that no patient refused participation.^38,42

Practitioner satisfaction

Only one study provided detailed feedback.⁴¹ This study asked practitioners and health technicians about their satisfaction with the system. Responses (n=10) were generally positive.⁴¹ Three additional studies^36,37,42 gave general but positive feedback about practitioner/emergency personnel satisfaction with the system.

Ambulance runs and times reported

Two studies^11,41 reported significantly lower response times when using telemedicine, although articles reported travel times differently.^11,40 Some accounted it as productivity (time in service),^11,46 with results showing telemedicine ambulance responses taking only 39 minutes, compared to a control time of 83 minutes. Another parsed out differences in travel time including five different components (activation, response, on scene, transport, delivery, and recovery)⁴¹ and found a statistically significant reduction of response time in all categories was observed across 100 patients. One additional study noted that telemedicine allowed for earlier initiation of treatment.³⁸ In the study where ambulance utilization was the outcome measure of quality, authors reported a substantial reduction in ambulance usage as a result of the telemedical intervention (control group had 74% usage vs 18% in the test condition), largely due to the alternative of a taxi ride being offered in place of ambulance transport.¹¹

Technical quality

To measure technical quality, studies either looked at ratings of transmitted data usability by end users or the number of times the transmission failed due to software/hardware/bandwidth difficulties. User ratings of data usability were positive with a few exceptions in individual studies that were related to bandwidth difficulties. Unsurprisingly, transmission quality – and therefore the usefulness of the data – was consistently dependent on network quality.

Eight articles specifically mentioned bandwidth, connectivity and/or data transmission issues. Of these eight, three reported transmission issues in less than 3% of the cases using telemedicine.^11,37,39 The remaining five articles reported data transmission issues ranging from approximately 5% of cases to more than 30% in one,⁴² although these issues were reported in a widely disparate manner. Physicians still found the transmitted video and photo data to be useful in making diagnoses and considered telemedicine equally as useful as voice-call interactions in making treatment decisions.^37,44

Evidence-based practice evaluation

The EPHPP tool was utilized to assess the rigor of each study. All but one⁴² were rated as weak (see Table 2). The most common concern related to blinding (i.e. whether those collecting data and study participants are aware of the research question), but this is a challenging issue because those conducting the study are typically the same individuals providing care, and obtaining patient consent without sharing the intent behind using alternative systems is difficult. If the blinding criterion were removed, the global ratings of only three studies would improve, as the EPHPP rating is sensitive to the number of weak ratings.

Table 2.

Quality assessment ratings of included studies using the Effective Public Health Practice Project Quality Assessment Tool (EPHPP).

Study	Selection bias	Study design	Confounders	Blinding	Data collection methods	Withdrawals and dropouts	Global rating
Bergrath et al., 2011	Weak	Moderate	Weak	Weak	Weak	Strong	Weak
Bergrath et al., 2013	Moderate	Moderate	Weak	Weak	Weak	Weak	Weak
Brockman et al., 2016	Weak	Moderate	Strong	Weak	Strong	Strong	Weak
Cabrera et al., 2002	Strong	Moderate	Weak	Weak	Weak	Moderate	Weak
Cho et al., 2015	Moderate	Weak	Strong	Weak	Weak	Strong	Weak
Curry and Harrop, 1998	Weak	Weak	Weak	Weak	Weak	Weak	Weak
Felzen et al., 2017	Moderate	Moderate	Weak	Weak	Weak	Weak	Weak
Kwak et al., 2009	Weak	Weak	Weak	Weak	Weak	Weak	Weak
Langabeer et al., 2016	Moderate	Moderate	Strong	Moderate	Weak	Weak	Weak
Langabeer et al., 2017	Moderate	Moderate	Strong	Weak	Weak	Moderate	Weak
Mandellos et al., 2004	Weak	Moderate	Weak	Weak	Strong	Weak	Weak
Pavlopoulos et al., 1998	Weak	Moderate	Weak	Weak	Weak	Weak	Weak
Yperzeele et al., 2014	Moderate	Moderate	Strong	Weak	Strong	Strong	Moderate

Discussion

The primary focus of this systematic review was to examine the state of research on the use of telemedicine in ambulances with particular concern for how technology use affects quality of care, cost of care, and levels of satisfaction with care, as well as the processes used to implement the telemedical system for general prehospital emergency populations.

For cost of care, the most important finding is the shortage of published data as only two studies addressed this issue. It is encouraging, however, that both studies found that telemedicine use decreases costs of care. However, both articles appear to describe integrated health systems where the ambulance service was part of the hospitals’ services, in urban areas, in different countries, and had conditions that make comparisons difficult (e.g. grant backing and government-funded basic life support). These cost savings appear consistent with recent research suggesting through modeling that, despite the initial investment, ambulance-based telemedical care demonstrates considerable potential to save costs and improve quality and length of life in stroke patients.²⁴

Satisfaction with telemedicine was measured in some studies by patient perception and in others by technician or provider perception, with only one study providing a depth of understanding on patient satisfaction.¹¹ This highlights the need for more research and standardized measures to better understand patient and provider satisfaction.

In terms of quality of care, telemedicine compared favorably to traditional care and results appear to favor telemedicine, albeit slightly. Telemedicine performed as well as, if not better, than controls in all but one study in which pain was reduced to acceptable levels, but was not as distinct as the face-to-face counterpart due to physician apprehension.⁴⁰ Increased quality of care may be due to the helpfulness of the technology in better assessing and preparing for patients’ conditions and needs.

For studies of travel time, time to care, and number of transports, the results were very encouraging. For example, one study found that when telemedical services were utilized, ambulances did not need to return to their bases nearly as frequently before moving to the next call, resulting in increased efficiency.¹¹

Most articles reported transmitting a variety of data types – audio, video, images, and vitals. In many cases, data transmission was relatively reliable, as challenges were overcome with time. Study populations appeared to be generally consistent with the general populations served, with the caveat that, in most studies included, there were specific protocols for the use of the telemedical equipment and, as such, not all medical conditions could be a direct match. Nevertheless, these seem to be favorably comparable.

We were surprised at how few articles discussed prehospital telemedical care in rural settings, where a generalized approach to ambulance-based telemedicine would be most beneficial. Despite apparent benefits, rural areas are less likely to have the demand or resources to support a specialized ambulance-based telemedical arrangement (e.g. a mobile stroke unit).²⁴ There appear to be instances of multiple studies in this review emerging from the same project. If so, we suspect more was done in rural areas than was reported.^38–40 Thus, analyses of a generalized approach to ambulance-based telemedicine in rural areas are needed.

The purpose of this review was to examine the triple aim of medicine in general prehospital telemedicine. There are other factors that affect the implementation and usefulness of telemedicine in this context that are worthy of mention. These include the often interrelated concerns of funding and reimbursement,^48–54 policy and legislation,^10,48,53,54 legal concerns,⁵⁵ infrastructure,^14,50,56,57 setting,^50,58,59 and personal preference.^{8,52,58,60,61} Unfortunately, these concerns remain ongoing and inadequately addressed.^50,62

Limitations

Any systematic literature review is inherently bound by the number and quality of the studies included in the review and this project is no exception. Overall, the literature regarding general use of prehospital telemedicine needs greater methodological rigor and a conceptual focus. Further research involving a wider variety of health conditions, political and economic circumstances, more rigorous models, standardized measures, and statistical analysis (with effect sizes) are needed to fully understand where this means of delivering care fits into the emergency medical situation in terms of improving healthcare at reduced costs while increasing patient and user satisfaction.

Conclusions

One of the most important observations found relates to the nature of the data reported. From a clinical perspective, usability of data (e.g. picture or transmission quality) is different from usefulness. Approximately half of the studies limited their evaluation to the technical specifications of the system. Usability of transmitted data and/or reliability of the transmission is good to ascertain; however, these are measures of technical quality as opposed to clinical usefulness – a more robust and valuable measure of the viability of ambulance-based telemedicine. We suggest that future studies conscientiously address the usefulness of telemedicine vis-à-vis the health and safety concerns emergency care professionals address as opposed to the usability of the data that is transmitted.

A second important observation is that non-inferiority studies are important in demonstrating the value of telemedicine to ambulance and emergency services.²⁹ A number of studies included in this review compared the ambulance-based telemedicine to a control condition, but these studies were in the minority. We strongly suggest that future studies ensure a controlled comparison to establish or refute the non-inferiority of an ambulance-based telemedicine system in specific emergency situations.

Closely related to concerns of non-inferiority is that of using validated measures. However, until recently, no validated measure of ED telemedicine existed, and to our knowledge, no specific validated measure of prehospital telemedicine currently exists.¹⁷ Thus, there is a great need for standardization in comparing variables relevant to ambulance-based telemedicine.

A final consideration would be the structure of the system in which the ambulance operates. For example, one study observed precipitous declines in ambulance transports when ambulance-based telemedicine was combined with the offer of a pre-paid taxi ride as an alternative when ambulance transport was deemed unnecessary.⁴⁶ However, such cost savings are not universally available and such an innovation would need to be built into the intervention. Furthermore, some patients may simply not pay their portion for the ambulance services, but if calling a taxi, non-payment for transit would not be an alternative. This could also vary by other factors such as level of integration of ambulances with the hospital system or transportation alternative availability, or the varying systems of care (federated vs fragmented) that exist in different nations. Such factors would influence the effectiveness of the intervention, although the cost savings could be substantial.

In addition to the content of the studies, we used the EPHPP tool to assess the strengths of the articles as well as the methodological needs of both present and future studies in this field. A general observation we have is that most studies struggle with methodological deficiencies (e.g. small sample size, lack of a comparison group), including some that were at times beyond the control of the authors (e.g. blinding, data collection methods).

Despite being in existence for a number of years, ambulance-based telemedicine and related research on this topic is still in its infancy. We have learned through this process that this modality offers great promise in terms of improving quality and reducing costs related to emergency care but has yet to reveal the full benefits and challenges of that promise.

Footnotes

Acknowledgement

The authors are grateful to Brent Collier undergraduate student at The University of Alabama, for his contribution to an early version of this work.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

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