Patient reported satisfaction levels with the use of telemedicine for general surgery—A systematic review of randomized control trials

Abstract

Background

As healthcare continues to evolve in the wake of COVID-19 pandemic, surgeons are presented with the opportunity to integrate telemedicine into healthcare in tandem with in-person consultations. We aimed to perform a systematic review of randomized controlled trials to assess patient satisfaction with telemedicine interventions in general surgery.

Methods

A systematic review was performed in accordance to the PRISMA guidelines. Randomized control trials (RCTs) were included. The risk of bias 2.0 assessment was used to determine potential bias.

Results

In total, 11 prospective, randomized trials involving 1,598 patients (mean age: 49.1 years) were included. Overall 45.5% (5/11) of the trials compared videoconferencing or telephone follow up to traditional in person follow up. Three studies used smart technologies which include activity tracking devices in combination with a website and mobile application (27.3%). The other 3 interventions involved accelerated discharge on post operative day (POD) 1 with tele videoconferencing on POD 2, Post-operative daily text messages with education videos and video calling capability, and supportive text messages post-operatively. Telemedicine was shown to provide similar levels of patient satisfaction compared to controls in all 11 included RCTs.

Conclusion

Patient reported satisfaction with the use of telemedicine is similar to standard of care models in general surgery. With several shortcomings confounding the results in support of telemedicine, further experimentation with telemedicine interventions will likely improve patient reported satisfaction with using telemedicine for peroperative surgical care.

Graphical abstract

Introduction

In early 2020, the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2 or COVID-19) pandemic triggered a paradigm shift away from traditional limit doctor-patient interaction through in-person consultations in attempt to reduce transmission of the virus [1]. Consequently, medical practitioners turned to telemedicine as the standard of care for the provision of care to outpatients. As outlined by the United States Department of Health and Human Services, telemedicine refers to the ‘use of electronic information and telecommunications technologies to support and promote long-distance clinical health care, patient and professional health-related education, public health and health administration’ [2]. Importantly, telemedicine reduced unnecessary contact between healthcare professionals and potentially vulnerable patients during the COVID-19 pandemic, while ensuring the healthcare needs of the those needing it were met during this challenging period in 21st century healthcare.

There are several potential benefits of telemedicine: Firstly, telemedicine has reduced costs for healthcare economies associated with staffing and resources, with more efficient use of healthcare professional's time [3]. Secondly, telemedicine is also beneficial in reducing travel costs implicated on ‘well’ patients who do not necessitate in person review in acute hospitals during periods of being asymptomatic or in times of remission [4,5]. Thirdly, virtual consultations typically result in less missed days of work/school [6]. Furthermore, patient perceptions of telemedicine include they believe their healthcare practitioners are more accessible to them through telemedicine in the form of video/telephone consultations, mobile phone applications, data trackers and interactive web pages. Such communication platforms have resulted in improvements in patient reported symptom control, improved preparation for procedures, and facilitating earlier diagnoses [7], [8], [9]. Therefore, telemedicine offers a holistic approach to the management of disease, providing patients the opportunity to facilitate healthcare providers to optimize the management of their disease on a day-to-day basis. For example, Elkjaer et al. illustrated benefit of educating patients with ulcerative colitis through a series of online lecture and also an interactive portal where patients could log their symptoms online [10]. Thereafter, this data was evaluated and used to develop a personalized treatment plan, specific to the needs of the individual, before these patients were encouraged to initiate the proposed treatment plan provided by their physicians. Once the plan was initiated, symptoms were logged by each patient for review by their doctors. The results of this study illustrated that 88% of patients in the intervention arm would be keen to use this platform for their prospective disease management. The many benefits of telemedicine must also be weighed against the potential pit falls of telemedicine. Not all studies have shown telemedicine to be cost effective with significant costs incurred due to monitoring of telemedicine systems [11]. External factors such as internet connectivity have been noted as a hindrance to the success of telemedicine [12]. A systematic review by Yi et al. highlights the barriers of using telemedicine in older adults and patients with cognitive impairment [13].

As healthcare continues to evolve in the wake of COVID-19 pandemic we are presented with the opportunity to integrate telemedicine into healthcare in tandem with in-person consultations. Therefore, robust evaluation of telemedicine practices in surgical practice is imperative as we attempt to enhance patient care in the post-COVID-19 era. Accordingly, the primary objective of the current study was to review previous prospective randomized control trials (RCTs) performed evaluating telemedicine interventions in general surgery practice to improve patient care.

Methods

A systematic review was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) checklist [14]. As this is a review article of previously published studies, local institutional ethical approval was not required. For the purpose of this systematic review, only prospective, randomized studies were included. All authors contributed to formulating the study protocol and it was then registered with the International Prospective Register of Systematic Reviews (PROSPERO): CRD42022356595.

Population, intervention, comparison, outcome (PICO) tool

Applying the PICO framework [15], the clinical research question the authors wished to address was:

• Population – Any patients aged 18 years of older who were planned for or had previously undergone any general surgery procedure who were being contacted in the pre-, peri-, or post-operative phases of treatment,

• Intervention – Any telemedicine intervention which patients were exposed to for providing patients with care,

• Comparison – Any standard-of-care intervention used (acting as a control intervention) for providing patients with care,

• Outcomes – Patient-reported satisfaction measured using a standardized satisfaction tool in relation to telemedicine and control interventions.

Search strategy

An electronic search was performed of the PubMed, EMBASE and Cochrane (CENTRAL) databases on the 28th May 2022 for relevant studies which would be suitable for inclusion in this study. The search was performed of all fields under the following headings: (Surgery[MeSH Terms]) AND (Telemedicine[MeSH Terms]). Included studies were limited to those published in the English language and studies were not restricted based on year of publication. For retrieved studies, their titles were initially screened, before the abstracts and full texts which were deemed appropriate were reviewed.

Inclusion and exclusion criteria

Studies meeting the following inclusion criteria were included: (1) Studies had to be trials of a prospective, randomized design, and (2) Studies had to report surgical patient satisfaction levels after telemedicine intervention or control. Exclusion criteria included: (1) studies of a retrospective or prospective, non-randomized design, (2) studies which did not assess patient satisfaction (3) review articles, or (4) conference abstracts, and (5) studies assessing patient satisfaction in surgery types other than general surgery (e.g.: orthopaedics, cardiothoracic, otorhinolaryngology, etc.).

Data extraction and quality assessment

The literature search was performed by two independent reviewers (M.G.D and E.H.B) using a predesigned search strategy. Duplicate studies were manually removed. Each reviewer then reviewed the titles, abstracts and/or full texts of the retrieved manuscripts to ensure all inclusion criteria was met, before extracting the following data: (1) first author name, (2) year of publication, (3) study design (including intervention and control), (4) trial registration number, (5) study title, (6) number of patients, (7) number of patients randomized, (8) Patient satisfaction with Telemedicine intervention. Risk of bias and methodological assessment of included studies was undertaken using the Risk of Bias 2.0 (or RoB 2.0) assessment tool [16].

Results

Literature search

The systematic search strategy identified a total of 3627, of which 2578 from PubMed, 790 from Embase and 259 from Cochrane. 366 duplicate studies were manually removed. The remaining 3261 studies were screened for relevance, before 43 full texts were reviewed for eligibility. In total, 11 RCTs fulfilled the inclusion criteria and were included in this systematic review [3,5,[17], [18], [19], [20], [21], [22], [23], [24], [25]].

Included studies

Of the 14 studies included, 36.4% were conducted in North American surgical research institutes (5/11) [17,19,21,22,25], 36.4% in European surgical research (5/11) [3,5,20,23,24] and one study was conducted in a surgical research institution in New Zealand [18]. In total 28.6% (4/11) of included studies evaluated the use of telemedicine in colorectal surgery [3,[20], [21], [22]], and 14.3% in each of the following; on bariatric surgery (2/11) [17,18], Liver transplants

(2/11) [5,19], one evaluated general surgery as a whole [23] and laparoscopic cholecystectomy, inguinal hernia repair or laparoscopic adnexal surgery (2/14) [24,25]. In total, 1598 patients (mean age: 49.1, Range 24.4–65.6) were recruited and randomised, 736 to control groups (46.1%) and 862 to a telemedicine intervention group (53.9%) (Table 1). The publication dates of includes studies ranged from 2018–2021 (Table 1).

Table 1.

Details of the 11 included randomized trials evaluating patient reported satisfaction levels with the use of telemedicine in general surgery.

Author	Year	Country	NCT Number	Surgery Type	Number	Mean age (range)
Alaa Sada	2021	USA	-	Bariatric surgery	20	49.4 (24.4–65.6)
Lee	2019	USA	NCT03878329	Liver Transplant	100	59.25
Damery	2021	UK	ISRCT1N4093266	Liver Transplant	54	48.9
Augestad	2020	Norway	NCT01600508	stoma patients	110	61.9
Den Bakker	2019	Netherlands	NTR5686	Colorectal surgery	151	62.6
Van Der Meij	2018	Netherlands	NTR4699	laparoscopic cholecystectomy, inguinal hernia repair or laparoscopic adnexal surgery	330	51.5 (41–61)
Bednarski	2019	USA	NCT02613728	minimally invasive colorectal resection	30	59
Cremades	2020	Spain	NCT03304509	General surgery	164	50
Harkey	2019	USA	NCT03258177	laparoscopic appendicectomy or cholecystectomy	442	36 (28–48)
Mata	2019	Canada	NCT03277053	colorectal surgery	100	60
lauti	2018	New Zealand	-	Sleeve Gastrectomy	83	46.3

USA; United States of America, UK; United Kingdom, NCT; National Clinical Trial, RoB; Risk of Bias 2.0 risk assessment tool, ISRCTN; International Standard Randomised Controlled Trial Number, NTR; Netherlands Trial Registry.

Measure of satisfaction

All 11 included studies used patient questionnaires to assess satisfaction [3,5,[17], [18], [19], [20], [21], [22], [23], [24], [25]]. Custom designed questionnaires were used in 54.5% (5/11) of studies [17,18,20,21,24,25]. Lee et al. used the Short Form 36 Quality of Life (SF 36 QoL) questionnaire, a quality of life questionnaire designed by RAND (research and development) corporation which is reliant on patients self reporting [19]. Damery et al. used the VSQ-9 (visit specific satisfaction questionnaire), a visit-specific satisfaction instrument created by American Medical Group Association [5]. Augustead et al. used the Out Patient Experience Questionnaire (OPEQ) a self administered questionnaire which assesses patient experience from an outpatient perspective [3]. Cremades et al. used a combination of the UK National Health Services Outpatient Questionnaire and the Telehealth Usability Questionnaire which was developed in 2016 to assess usability with newer technologies [23]. Finally, Mata et al. used S-CHAMPS, the Consumer Assessment of Healthcare Providers and Systems Surgical Care Survey [22]

Post operative telemedicine interventions

Patient satisfaction in the postoperative period was examined in 81.8% (9/11) of included studies [3,5,[17], [18], [19],[21], [22], [23],25]. Of these 5 of the trials compared videoconferencing or telephone follow up to traditional in person follow up in an outpatient setting (5/9, 55.6%) [3,5,17,23,25]. Of these trials, one had the addition of allowing patients to pre submit three questions prior to their videoconferencing follow up, which showed greater patient satisfaction when compared to control with an average VSQ-9 score increasing form 49.7 to 74.4 compared to control increasing form 50.3 to 64.5 [5]. The other 4 trials showed satisfaction with telemedicine to be similar or non-inferior to the control. A study by Bednarski et al. compared in patient follow up on post op day (POD) 2, to tele videoconferencing on POD2 with patients who had accelerated discharge on POD1 [21]. There was no significant difference between TM and C arms for any of the questions from the satisfaction questionnaire. A study by Lauti et al. used supportive text messages post sleave gastrectomy to reduce weight regain, participants who received text messages found them beneficial and would have like them to continue after the study [18]. 22.2% (2/9) [19,22] used smart technologies with the aim of enhancing post operative recovery. Smart technologies included a smart table, peripheral Bluetooth devices and a mobile app which allowed, vitals monitoring, educational videos, facetime capability, daily text messages etc. Both studies found similar levels of patient satisfaction between the intervention and control arms, [19,22].

Combined pre-, peri- and post- operative telemedicine interventions

The use of telemedicine in the pre, peri and post operative period was examined in 18.2% (2/11) of included studies [20,24]. Both studies gave the control group usual care as well as access to a placebo website consisting of a patient information leaflet. The intervention groups received a care programme which included a website, a mobile phone application, an activity tracker and an electronic consultation (eConsult) function. Van Der Meij et al. showed patients in the intervention group on average gave a higher rating to the care programme, 7.2 vs 6.3 with similar overall satisfaction of 7.5 vs 7.1. Den Bakker et al. did not directly compare satisfaction but gave a mean attitude score of 7.1 for the website, 7.5 for the app and 7.1 for the activity tracker.

Overall 81.8% of included studies directly compared satisfaction in the control arm to the intervention arm [3,5,17,19,[21], [22], [23], [24], [25]]. Of these 11 studies 8 found the use of telemedicine to be equivocal to the control arm [3,17,19,[21], [22], [23], [24], [25]] and one favoured telemedicine intervention [5]. 2 of the 11 studies did not directly compare satisfaction between telemedicine and control. Den Bakker found participants attitude mean score towards website, app and activity tracker were 7.1, 7.5 and 7.1 respectively [20]. Lauti noted that 78.6% of participants wanted to continue receiving the intervention after completion of the trial [18]. Details of results are outlined in Table 2.

Table 2.

Details of the outcome of interventions used in the 14 included controlled trials in attempt to patient satisfaction with the use of telemedicine in general surgery.

Author	Year	Control	N	Intervention	N	Assessment tool	Outcome
Alaa Sada	2021	In Person Follow up	9	Video Follow up	11	Custom designed survey	Patients’ acceptance and preference of telemedicine postoperative visits were noninferior to in-person visits
Lee	2019	SOC with Home Monitoring Paper Log	50	Postop daily text messages, education videos, and FaceTime capability	50	SF-36 QoL questionnaire, at discharge and at 90 days	Patient satisfaction was improved in some areas with THMP compared to SOC because patients felt that they were being monitored more closely with the THMP devices.
Damery	2021	Standard face-to-face outpatient appointment	25	Videoconferencing follow up. Patients could submit 3 Qs prior to appointment, with recordings available after	29	VSQ-9 survey with satisfaction on a 5-point scale (poor, fair, good, very good, and excellent), transformed into a 0 to 100 linear scale	Average VSQ-9 score increased in the telemedicine arm from 49.7 at baseline to 74.4 after 12 months compared to VSQ 9 bassline score of 50.3 Average VSQ TM: Baseline 49.7, after 12 months 74.4 Average VSQ C: baseline 50.3, after 12 months 64.5
Augestad	2020	Regular stoma follow-up at out- patient clinic.	58	Telecommunication (TC) follow-up were Stoma nurses organized TC at 0 – 3 (defined as baseline), 6, 9 and more than 12 months	52	OutPatient Experience Questionnaire (QPEQ)	There was no significant differences in the experience of patients followed up the outpatient clinic when compared to the TC consultation group. When given the choice most patients in the TC group chose to have their next consultation via TC.
Den Bakker	2019	Usual care and access to a placebo website	78	eHealth care program which included; a website, a mobile phone app, an activity tracker, and the possibility to ask questions via an eConsult	73	Custom designed adherence and satisfaction questionnaire completed 3 months after the surgical procedure, and semi structured interviews	Participants attitude mean score; website 7.1 (1–9), app 7.5 (1–10) and activity tracker 7.1 (1–10)
Van Der Meij	2018	Usual care and access to a placebo website,	171	Access to a website, mobile app, and an activity tracker. Participants could develop a personalised convalescence plan, access information about the perioperative period by text and video animations, use a monitor providing personal feedback on the recovery process, and had use of an e-consult function	173	Custom designed satisfaction questionnaires at 4-week period before surgery (T0), 1 week (T1), 3 weeks (T2), 6 weeks (T3), 3 months (T4), and 6 months (T5) after surgery	Participants in the invention group gave a higher rating to the care programme they had access to, 7.2 (SD 1.7) compared to the control arm, 6.3 (SD 2.4). Overall satisfaction did not differ between groups with mean score in the intervention group of 7.5 (SD 1.7) compared to 7.1 (SD 2.3)
Bednarski	2019	Standard Postoperative care with discharge on POD2	16	Accelerated discharge on postoperative day (POD) 1 followed by televideoconference on POD 2	14	20-item custom designed survey of patient satisfaction was evaluated at POD 30	There were no significant differences between the treatment arms for any of the questionnaire items. Nearly all respondents in both arms did not feel they needed to be kept in the hospital for a longer period of time to recover from surgery
Cremades	2020	Follow-up in the outpatient clinic	90	telemedicine follow-up through a video call	74	United Kingdom National Health Service outpatient questionnaire combined with the Telehealth Usability Questionnaire (TUQ)	The median global satisfaction score was 5 in both the conventional and telemedicine group with no statistically significant difference. When patients in the telemedicine group were asked if they would accept the use of telemedicine as part of their medical treatment on an ongoing basis, they rated the proposition with a median score of 5 (range 1–5)
Harkey	2019	Traditional in person visits	147	Video based virtual visits (VV)	295	Satisfaction and convenience were measured by custom designed survey (11 multiple-choice questions and 2 open-ended questions; eDocument 1) after the post-discharge visit	There was no difference in patient reported satisfaction between groups, but patient reported convenience was higher in the video based virtual visits. 78.8% of patients in the VV group preferred future visits using the virtual platform, compared to 21.1% in the control group.
Mata	2019	Standard preoperative education and placebo intervention	50	Standard preoperative education and the use of a mobile device app for postoperative education and self- assessment of recovery including; Milestones checklist, Daily Clinical Questionnaires and Education	50	Consumer Assessment of Healthcare Providers and Systems Surgical Care Survey (S-CAHPS) questionnaire	Overall satisfaction was high, with no differences in median score for each item between the intervention and control groups. When asked “I felt satisfied with the care if received” the median response was 4 for both the intervention and control group
lauti	2018	Usual care which consisted of discharge if appropriate, or ongoing specialist follow-up as required	42	Post operative text message support (TMS) which consisted of a daily text message delivered each morning for a period of 1 year together with usual care	41	Custom designed satisfaction survey, undertaken at the 12- month assessment on completion of the intervention	the majority of participants who received TMS were satisfied and felt that the intervention made them feel supported, motivated and assisted in reducing WR. 78.6% of participants wanted to continue receiving daily text messages, 80.9% felt it helped minimise weight regain, 95.2% of patients felt the messages helped with motivation and 75.2% felt the messages help them feel supported

N; Number, SOC; Standard of Care, THMP; Telemedicine-based Home Monitoring Programme, VSQ; Visit Specific Satisfaction Instrument, POD; Post Operative Day, TC; Telecommunication, VV; Virtual Visits, TMS; Text Message Support.

Discussion

The practice of using telemedicine has increased significantly in recent years, which likely coincides with the increased use of telecommunications in day-to-day life in the 21st century and also in the wake of the COVID-19 pandemic [26]. This data presented in the current systematic review coherently illustrates this, as all of included studies were performed in the past 5 years [3,5,[17], [18], [19], [20], [21], [22], [23], [24], [25]]. Telemedicine has been extensively studied as a whole [27], as well as studies for individual specialties demonstrating a clear trend towards an increase in the use of telemedicine [28], [29], [30]. Despite this trend, there remains a paucity of scientific studies appraising the use of telemedicine in general surgical practice, with this study representing the first systematic review examining patient reported outcomes in relation to the use of telemedicine in this field. The most important finding in this study was the data outlining equivocal patient reported satisfaction following telemedicine interventions compared to use of traditional standard of care models. Moreover, this study also illustrated that post-operative follow up using video or telephone consultations are the most common telemedicine intervention in use at present, with telemedicine communications through interactive websites, mobile phone applications, and data trackers less commonly evaluated in general surgical practice (Table 3).

Table 3.

Risk of bias assessment 2.0.

Author	C1	C2	C3	C4	C5	Overall
Alaa Sada	High	Low	Low	Con	Low	Low
Lee	Low	Low	Low	Low	Low	Low
Damery	High	Low	Low	Low	Low	Low
Augestad	Low	Low	High	Low	Low	Con
Den Bakker	Low	High	Low	Con	High	High
Van Der Meij	Low	Low	Low	Con	Low	Low
Bednarski	Low	Low	Low	Con	Low	Low
Cremades	High	Low	Low	Low	Low	Low
Harkey	Low	Low	High	Con	Low	Con
Mata	Low	Low	Low	Low	Low	Low
lauti	Low	High	Low	Con	High	High

C1 = Bias due to Randomisation.

C2 = Bias due to deviation from intended intention.

C3 = Bias due to missing outcome data.

C4 = Bias in measurement of the outcome.

C5 = Bias in selection of reported results.

Con = Some Concerns.

It is important to highlight that 'usability’ may have been a barrier confounding the potential success of telemedicine interventions, particularly in studies where patients used interactive websites, mobile phone applications, and data activity trackers [20,24]. For example, Van Der Meij et al. reported implementation scores of 61–65% for their five interventions (i.e.: website, mobile phone app, e-consult, telephone appointment, and activity tracker) before proceeding to highlight technical difficulties provided a technical barrier for participants to use these telemedicine interventions [24]. Importantly, just 7% of patients requested an electronic consultation to overcome this issue [24], illustrating the potential challenges of telemedicine in the provision of healthcare for certain patients, who may have had limited previous exposure to technology in the past. In their study which evaluated the utility of mobile device to improve patient adherence to an advanced recovery after surgery programme, Mata et al. reported no improvement in adherence despite telemedical communications with patients [22]. In this study, there were high levels of engagement with the application on days 1 and 2 post-operatively, which decreased significantly on day 3 and thereafter. In addition, Den Bakker et al. reported the positive ease of use for their eHealth care programme, however not all functionalities (i.e.: website, app, e-consult, activity tracker) operated at a satisfactory level to improve outcomes [20]. Despite these reported issues with usability, patient satisfaction was still relatively high in each of the three aforementioned studies, however optimisation of intervention usability is required before an increase in patient satisfaction is likely to be observed.

The current study illustrates several important advantages and disadvantages of using telemedicine to deliver satisfactory surgical care. In their study, Harkey et al. reported improved patient satisfaction with the cost effectiveness of using telemedicine to delivery their care, with traditional care associated with increased transport costs, childcare costs, and wages lost due to time out of work [25]. Importantly, these costs were all mitigated by telemedicine consultations, supporting the use of telemedicine as a facet of prospective patient care. Furthermore, Cremades et al. outlined the reduced institutional costs with respect to room space, administrative staff, post-consultation cleaning, and reduced turnover time between consultations [23]. Contrary to this, an Australian paper by Snoswell et al. states that many studies have not demonstrated overall cost savings due to the cost of administering and monitoring telehealth systems, they suggest that implementing telehealth should be motivated by benefits other than cost reduction [11]. Damery et el. detailed a reduced consultation duration when using telemedicine relative to in person consultations, with less ‘small talk’ reducing the time taken for each consultation [5]. While telephone and video consultations between patients and their healthcare providers are widely used across several medical specialties, issues in relation to connectivity also provides an inherent challenge to ensuring the delivery of satisfactory care by the healthcare professionals and adequate engagement from patients. In the current study, connectivity issues were not as problematic as may have been anticipated in the included studies, with patient care transferred to in person consultations [3,5,17,23,25].

This systematic review is subject to several limitations. Firstly, the reliance upon patient satisfaction as a subjective outcome measure has many limitations, as previously outlined in depth by Ring et al. [31]. Furthermore, satisfaction as an outcome measure can demonstrate the ‘ceiling effect’ [32], which occurs when high scores are reported for both the intervention and control arms, limiting the ability to detect significant differences in outcomes (as clearly demonstrated by Cremedes et al. where the median global satisfaction score was rated 5/5 for both telemedicine and control groups respectively [23]). Secondly, several of the studies included in this systematic review failed to use validated instruments and tools to measure patient satisfaction, with heterogeneity in the instruments across the included studies. Thirdly, this study relied solely on MeSH terms for the systematic search, making it possible that certain studies meeting eligibility criteria may not have been captured in the search. Lastly while this systematic review reports on patient satisfaction, it does not determine clinical and surgical outcomes associated with the use of telemedicine. While patients may be satisfied with their care, further objective review is required to determine the implications of telemedicine on clinical outcomes.

In conclusion, this current systematic review demonstrates that patient reported satisfaction with the use of telemedicine is equivocal in the minds of patients to standard of care models in general surgery. With several shortcomings (such as usability) confounding the results in support of telemedicine, further experimentation with telemedicine interventions will likely improve patient reported satisfaction with surgical care delivered using telemedicine use in clinical practice.

Funding

None received.

Declaration of Competing Interests

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.