Introduction

Hearing loss in childhood can significantly impact the development of spoken language, as well as societal inclusion, access to information and knowledge, and eventually desirable academic and vocational academic outcomes. To reduce the impact of hearing loss, it is pertinent to detect congenital hearing loss before 3- 6 months of age [1] through newborn hearing screening programs and also introduce school screening programs to mitigate the consequences of unidentified late onset and other preventable hearing losses.

In 2013, the Government of India launched a national program to screen and identify any defects, diseases, deficiencies, and disabilities among children from zero to 18 years of age in order to encourage early identification of disabilities. A health team, at the village level, led these screening efforts, referring individuals who fail the screening to the Early Diagnostic Centre (EDC) at the district General Hospital (GH) for diagnosis. Further, post confirmation of disability, the individual is directed to the District Differently Abled Welfare Office (DDAWO) for welfare benefits, aids and appliances, and early intervention. In 2015, the ‘Mobile Therapy Unit’ was implemented through the State Commissionerate for the Differently Abled to improve consistency of rehabilitation services, increase last-mile coverage, and overcome the challenge of patient’s access to services. This service is provided with existing professionals available through District Differently Abled Welfare Office or local non-governmental organizations (NGOs). However, this initiative is also challenged by higher demand on professional’s time who are engaged in both clinical services and administrative work. A recent situational analysis confirmed this mismatch of demand versus need [2].

Tele-practice/ tele-health has been explored as one of the options to overcome the challenges of demand versus capacity and access barriers. There is a growing body of evidence on the use of telehealth in hearing health care, including screening [3], diagnostic assessment [4], hearing aid fitting [5] and rehabilitation [6]. With more than 3.74 billion smartphones and 4.92 billion mobile phones worldwide, mHealth applications are showing potential to increase access to low- and middle-income countries (LMICs) [10]. Several studies from Africa, the United States, and India have shown promising outcomes in reaching the rural community through tele-practice for individuals with hearing and speech-language disorders [7–9,11–13]. Despite these, there have been only a few attempts to investigate a comprehensive diagnostic audiology solution [7,14,15]. Even these, however, have focused only on diagnostic testing and did not include rehabilitation. Furthermore, only a few studies in a high-income country examined the outcomes of implementing tele-audiology in a health care system [7]. There are no such reports from the low-middle income country context.

Therefore, we developed a comprehensive tele-practice model to identify and rehabilitate children with hearing loss under six years of age in rural communities, and integrated it into public-sector health services in a rural district in Southern India. The proposed intervention is complex as it involves multiple steps (as stated above), multiple departments (District Differently Abled Welfare Office, Early Intervention Centre, Non-Government Organizations), and many stakeholders at various stages of implementation (Audiologist and Speech Language pathologist, child with disability, caregivers, parents, nurses, special educators, government officers, non-professional staff). The intervention necessitates that stakeholders adopt technology to a greater extent than is currently used, thereby altering their work process. We identified and mapped implementation characteristics to the Consolidated Framework for Implementation Research (CFIR) [16]. The model was designed for implementation in four blocks of a rural district (Perambalur Block, Veppanthattai Block, Alathur Block, and Veppur/Kunnam Block). Prior to the model’s finalization, several stakeholders from the State Commissionerate for the Welfare of Differently Abled, Departments of Health, Social Justice and Welfare, and Education, as well as parents of children with and without disabilities, were involved to ensure model optimization and convergence of efforts toward early identification and intervention [2].

In this model, nurses in Upgraded Primary Health Centers were to be trained to screen for hearing impairment using a validated tablet-based screening device (see https://sresht.godaddysites.com/resources) in order to triage disabling hearing losses (>=60 dB HL) as defined in the RPWD Act 2019. For individuals who ‘refer’ the hearing screening, tele-diagnostic testing would be delivered remotely from the university’s SRESHT lab to children in a mobile-van with an audiology test facility at each of the four block’s Upgraded Primary Healthcare Centers. Staff from NGOs or government Early Intervention Centres served as tele-facilitators. Finally, individuals identified were to receive tele-rehabilitation services at the Block Resource Centers of the ‘Education for All’(Sarva Shiksha Abhiyan) scheme of the government of India (SSA-Block Resource Center), with the assistance of computer assistants/SSA teachers and under the supervision of a remote audiologist/speech language pathologist/auditory verbal therapists (Fig 1).

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Fig 1. Comprehensive Tele-practice model.

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The aim of the current study was to evaluate the pilot outcomes of this comprehensive tele-practice model. The objectives were: (i) to evaluate the outcomes of training tele-facilitators to assist in remote diagnostic hearing assessment and rehabilitation services; (ii) to evaluate the limited -efficacy outcomes of the pilot. Limited-efficacy measure is defined as an analysis that uses a convenience sample, intermediate rather than final results, shorter follow-up periods, or has limited statistical power [17]. Additionally, it involves evaluating the patient’s acceptance and satisfaction with the tele-diagnostics and telerehabilitation components of the comprehensive tele-practice model.

Method

Procedure

The procedure is explained in a sequence of four steps

Step 1: Training and assessment of the tele-facilitator’s knowledge and skill.

The District Differently Abled Welfare Office deputed a special educator and a trainee special educator for hearing impairment (HI) to train them as tele-facilitators to assist with tele-diagnostics and tele-rehabilitation. Three audiologists conducted the training over two days, for five hours per day. The training primarily covered aspects of internet connection, the use of the TeamViewer application (version 15.40.8) to connect remotely to the audiologist, the purpose of the test, the setup of equipment in the mobile van, instructions to the parent on the test procedure, patient preparation for testing, equipment connections, and the placement of transducer, probe, and electrodes on the patient.

During the training period, we conducted a hands-on training session to acquaint them with the software, equipment connections, and placement of transducer/probe/electrode. At the end of the training session, a procedure manual (see S1 file) along with a video demonstration developed in English and local language (Tamil) (available at https://www.youtube.com/watch?v=xEKYm4sKnWg)

A questionnaire (see S2 file) was used to assess the tele-facilitator’s knowledge and an Objective Structured Clinical Examination (OSCE) (see S3 file) and a labeling form with images of the equipment were used to assess the skill (see S4 file). We developed the questionnaire for knowledge assessment using Bloom’s taxonomy [18] and included 10 close-ended questions. Five of the questions were about technical factors such as internet connection, audio-video call, and troubleshooting, while the other five were about audiological test processes. The OSCE checklist assessed tele-facilitator’s ability to use the videoconferencing application, identify parts of the equipment, placement of the transducers, connections of the equipment, and instruct the patient for the testing. The first and third author carried out the OSCE examination.

The labeling form with images of the equipment was used to assess the proficiency in labeling the components of the equipment. Correct responses received a score of one, while erroneous responses received a score of zero. The knowledge questionnaire, OSCE checklist, and labeling forms were validated for relevance, adequacy, and appropriateness by two audiologists (one with 3 years of experience and one with 14 years of experience in tele-practice) and an auditory verbal therapist with 15 years of experience.

Step 2: Tele-diagnostic audiological testing.

Patient site set-up:

The tele-diagnostic testing was conducted in a mobile-van near the Upgraded Primary Healthcare Center with 4G internet bandwidth enabled using a mobile phone hotspot. Internet was available through a few limited service providers in some of the locations, hence multiple service providers had to be explored. This van was equipped with a bed, fan, power sockets, and seating facilities. The mobile-van was scheduled to visit each Upgraded Primary Healthcare Center located at all 4 blocks once in a month on a fixed day of the week. The mobile-van set-up is shown in Fig 2.

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Fig 2. Set-up of the mobile-van.

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The test equipment included video-otoscopy (Firefly Pro DE550), Pure Tone Audiometry (PTA) (Harp Inventis Plus calibrated to ANSI S3.6 standards), Oto-Acoustic Emission (OAE) calibrated as per EN 60645-6:2010 standards, and Auditory Brainstem Response (ABR) calibrated as per EN 60645-7:2010 standards (Neuro-Audio version 1.0.104.1) was used for the diagnostic assessment of hearing.

The laptop (Lenovo) was pre-installed with software for remote testing. The Teamviewer application (version 15.40.8) and V-See application (version 4.17.1) were installed on the laptop. A web camera was connected to the laptop for videoconferencing on the remote site. These features helped the audiologist to view the placement of transducers, otoscope, probe tip, insert tip and electrodes with more clarity.

Set-up at the audiologist site:

A laptop (Acer) with 8.00 GB RAM and 11thGen Intel(R) Core (TM) i5-1135G7@ 2.40 GHz was used by the audiologist at the University to provide tele-diagnostic evaluation and tele-rehabilitation services. The laptop was configured with Teamviewer application (version 15.40.8) and V-see application (version 4.17.1) for the audiologist to remotely access the laptop.

Testing method:

All children who required diagnostic testing either from the hearing screening using SRESHT screener or suspected of hearing loss by government pre-school teachers (anganwadi teachers), village health nurses, or community workers were asked to follow-up at the mobile van during the scheduled visit to the block level Upgraded Primary Healthcare Center, closest to the child’s home. The tele-facilitator provided instructions about the test prior to the test procedure. The remote audiologist clarified any doubts via videoconferencing. The audiologist used remote computing to conduct tele-testing in real-time for all test procedures, adhering to standard test protocols.

The audiologist counseled all children diagnosed with hearing loss to enroll for hearing aids/cochlear implants at the District Differently Abled Welfare Office, the district General Hospital, or other nearby government centers. The parents were also given the option to use temporary hearing aids (Tarang- 4 channel programmable affordable indigenous digital hearing aid) provided through the project and programmed according to their hearing loss, until they bought their own hearing aids/Cochlear implant. We emailed all the patient reports to the parents and also made them available to the District Differently Abled Welfare Office.

Step 3: Tele-rehabilitation.

A dedicated noise-free room was chosen in the SSA Block Resource Centers. The VSee video-conferencing application was installed on the laptop available at the respective Block Resource Centers. A computer assistant available at the center assisted with the process. The facilitator identified available therapy materials at the Block Resource Center for use during the sessions. The facilitator procured additional therapy materials or asked the parent to bring them for the session. Each therapy session lasted for 45 minutes.

Step 4: Parental satisfaction with tele-practice (diagnostic and rehabilitation).

To assess parental satisfaction with tele-diagnostic evaluation, a 10-item questionnaire with open and closed ended questions was used. Relevant items from an existing questionnaire available in Tamil was taken from Ramkumar et al. (2016) [35]. The tele-rehabilitation satisfaction questionnaire was modified and face validated in Tamil language from the one developed by Jahromi & Ahmadian (2018) [19]. This questionnaire had 11 questions (5 close-ended, 5 close-ended with 1 open choice and 1 open-ended question).

Both the satisfaction questionnaire’s (tele-diagnostic and tele-rehabilitation) relevance, adequacy, and appropriateness were face validated (see S5 file) by two audiologists and one auditory verbal therapist (AVT). Following the tele-diagnostic assessment, the tele-diagnostic satisfaction questionnaire was administered. The tele-rehabilitation satisfaction questionnaire was administered following two tele-rehabilitation sessions (see S6 file).

Results

Limited- efficacy outcomes

Rate of follow-up for tele-diagnostic evaluation.

In all, 41 children (age range of 5 months to 5 years 3 months) were screened by nurses using the SRESHT screener at the four Upgraded Primary Healthcare Centers of the district. Of them, 11 (26.8%) had ‘refer’ results in the screening and 10 (90.9%) of them followed up for tele-diagnostic evaluation. A parent of one child was not willing to complete a confirmatory diagnostic hearing evaluation as she did not suspect/perceive any problem. Table 1 provides month-wise data on screening and follow-up post pilot. In addition, two children directly came for tele-diagnostic evaluation without undergoing hearing screening based on suspicion of hearing loss. We confirmed that 11 out of the 12 children had hearing loss.

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Table 1. Screening and follow-up for tele-diagnostic testing for children with refer results post pilot.

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For comparison, we collected month-wise data on the number of children screened at the district Early Diagnostic Centre in the General Hospital over a three month period from January 2023 to March 2023 (Table 2). An audiologist screened 459 children at birth using an OAE screener. There was only one referral from the screening, and this child received the diagnostic evaluation by traveling to a nearby city. Therefore, the number of children followed up for tele-diagnostic evaluation before the commencement of the pilot was one and after was 12.

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Table 2. Screening and follow-up for diagnostic testing for children with refer results pre pilot.

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An age-appropriate tele-diagnostic test battery was conducted to confirm hearing loss among 10 children who were referred from Upgraded Primary Health Centres and two other children who were referred directly from Early Diagnostic Centre at the General Hospital. Out of the 12 children who were tested, one child had normal hearing sensitivity, seven children had confirmed sensorineural hearing loss, two children with bilateral minimal to mild hearing loss and bilateral mild to moderate hearing loss were suspected with neuro-maturational delay and two children had conductive hearing loss. The demographic details, case history, test performed and the diagnosis of all the 12 children is tabulated (see Table 3).

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Table 3. Demographic data, case history, tests completed and provisional diagnosis for tele-audiology diagnostic children.

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Time lapse between screening and diagnosis for hearing impairment before and after the commencement of the pilot.

The time lapsed since suspicion/screening to diagnose a child with hearing impairment for Group 1 (post-pilot) and Group 2 (pre- pilot) are represented in Figs 3 and 4 respectively. The median number of days lapsed pre- pilot and post -pilot was calculated for both groups. The median time taken to diagnose a child for hearing using tele-practice (Group 1) was eight days, whereas pre- pilot, the time taken was 216 days (Group 2).

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Fig 3. Time lapse between hearing loss suspicion/screening to tele-diagnosis.

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Fig 4. Time lapse between hearing loss suspicion/screening to diagnosis.

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Rate of follow-up for tele-rehabilitation before and after the commencement of the pilot.

In all, five children attended tele-rehabilitation at the SSA-Block Resource Center. Four of these children were cochlear implant users who received special education at the Early Intervention Centre. Another child, identified from the pilot implementation, was directly enrolled in tele-rehabilitation using temporary hearing aids provided by the project. Each session was carried out for 45 minutes, where the initial 10 minutes were to review with the parent regarding home plan activities. At the end of each session, the goals and activities were reiterated to the parents and discussed any doubts/concerns regarding the child’s progress. Table 4 tabulates the number of sessions attended for a period of 3 months before and after the pilot’s commencement. The median number of sessions pre- pilot was zero and post- pilot was two.

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Table 4. Rate of follow-up for tele-rehabilitation before and after the commencement of the test bed (refer the number given for child from Fig 3).

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Discussion

This study explored the pilot outcomes of the first known effort to integrate tele- practice services for childhood hearing loss in the public health system of a low middle income country [34]. Very limited studies have explored the outcomes of providing comprehensive hearing care using tele-practice [7,14,15].

Tele-facilitators in audiological testing are required at the patient site to support placement of probes, electrodes, and transducers as required and also provide technical ftcplosort [20]. In a scoping review, it was identified that predominantly audiologists, audiology students, and unspecified technicians served as tele-facilitators and limited studies reported details of the training they had received [21]. In the current study, we trained a special educator, deputed from the government Early Intervention Centre, to support remote testing as needed. Such capacity building is necessary to optimize shared resources to support implementation of services where none exist. We also trained a second trainee special educator as a backup to prevent service discontinuity due to absences.

The comprehensive model of tele-practice was conceptualized as a community-based model that includes children from birth to 6 years, to overlap with the Government of India’s age criteria for early identification. The SRESHT screener supports the triaging of 40% (60 dB HL) hearing loss from the community to the nearest block level Upgraded Primary Health Centre for tele-diagnosis. However, due to the lack of diagnostic services in the district General Hospital, there was considerable demand for diagnostic services among parents and caregivers who had suspicions about their child’s hearing.

On the other hand, district General Hospital had catered only to the ‘at birth’ population using the OAE screener, which is capable of triaging even milder hearing losses (>25-30 dB HL). While the coverage was higher at birth, older children with hearing loss were unidentified and missed. In low-middle income countries, the age of identification of hearing loss still continues to be higher [22] and there are only a few screening programs that have focused beyond the newborn stage.

The comprehensive tele-practice model integrates screening at a primary health facility to facilitate block-level triaging of individuals requiring diagnostic testing. However, during the test bed, it was noted that, the suspicion and referrals were predominantly from the SSA special educators (educational department) and then were redirected to the Upgraded Primary Health Center for screening. Therefore, screening at the SSA- Block Resource Center can also be explored to assess if triaging is better compared to Upgraded Primary Healthcare Center- based screening.

Despite the use of a test battery approach, the children underwent only the minimum required tests to diagnose their ear and hearing condition. We optimized the use of resources like mobile van availability, internet bandwidth, and limited time to obtain an accurate diagnosis. Sometimes, some tests were not conducted if children were less co-operative.

Even though the follow-up rate at the district General Hospital was 100% in comparison to 90.8% for tele-diagnosis, it should be noted that only one child needed diagnostic assessment in the former. Therefore, this may not be a true indication of the follow-up compliance. The loss-to-follow-up rate for tele-diagnostic testing was 9% in the current study, which is much lower than that reported in several EHDI programs in India [23–27].Lower loss to follow-up is also reported in few other studies that implemented tele-diagnostics in EHDI in Canada [14] and the USA [7].This suggests that in a tele- practice model the loss to follow-up rate is less when compared to in-person testing.

We found that the time between the suspicion of hearing loss/screening to diagnosis was less for the children who availed tele-diagnostic testing. This confirms that having local resources within a block enables better follow-up and timely diagnosis. Similar results were found earlier in a study where the time taken between second screening and tele-ABR assessment was less in a rural community-based program with a median interval of 30 days [29].

The findings suggest the potential for improvement in the rate of follow-up for tele-rehabilitation but do not assert it, owing to the small sample. Improvement in the number of sessions attended was also reported in a tele- auditory verbal therapy program in Logan, USA [28]. The coordinated follow-up and scheduling by the tele-facilitators and the therapist based on the availability of the parent/caregiver is likely to have promoted better follow-up.

The majority of the parents in the current study did not have any difficulty during the testing, but some reported poor ventilation in the mobile-van which caused difficulties for the child to be comfortable and cooperative for the testing. While most parents preferred tele-testing within their block, a few expressed a preference for in-person diagnostic services in nearby cities. Even though during COVID-19 there was a surge in tele-practice across all health disciplines, there exists a preference for in-person services [30,31]. Therefore, tele-practice can augment services where none exist and until suitable infrastructure and resources are allocated.

The current study also suggests that caregivers found the tele-rehabilitation to be acceptable, trustworthy, and the location (at block level) to be suitable, comfortable, satisfied with the level of communication with the therapist, and had met their expectations. As they had trust in the clinician, they were also likely/very likely to continue receiving tele-rehabilitation services. In another study too, high satisfaction was reported for tele-consultations for pediatric health [33].Trust in audio-video communication was reported by majority of the patients, which is likely to have resulted in better satisfaction [19]. These results are found to be similar with another study [32], where majority of them felt that tele-therapy was convenient, cost-effective and improved the attendance of the sessions. But some had reported about the increased use of gadgets and screen time for their children.

There are limitations to our current findings, owing to small and convenient sample size (due to test-bed), as well as the limitations of a questionnaire-based approach that does not provide an in-depth, unbiased perspective. These will however be explored on an ongoing basis to study the feasibility outcomes of the overall implementation in the future.

Conclusion

Overall, it can be concluded that this comprehensive tele-practice model can be effectively implemented to overcome professional shortages, and was beneficial in reducing time gap between screening/suspicion and diagnosis and also enhanced attendance for rehabilitation. The pilot helped to identify the aspects of the model that are suitable (e.g., block level implementation of diagnostic and rehabilitation services, community level screening including older children) and the aspects that need adaptations (ventilation in the mobile van, center-based tele-testing within the block, multi-adapter internet dongles for more stable internet, or a mobile-phone call for audio communication, with videoconferencing alone through the desktop-based software). This project is on-going, and suitable adaptations are made based on the findings of the pilot. The feasibility outcomes of implementing this model will be studied using the limited-efficacy measures, economic analysis, as well as qualitative methods to assess the various other constructs of Bowen’s framework.

Supporting Information