Abstract
Purpose:
Assistive technology (AT) has recently received considerable attention around the world. Studies have shown poor access to assistive technology for visual impairment (ATVI) in schools for the blind in India. The present article aimed at designing a school-based model to improve AT access in schools and provide hands-on training, and identify types of ocular morbidities present among students.
Methods:
The vision rehabilitation (VR) team of a tertiary eye-care center visited schools for the blind as a part of community-based VR services. The team conducted a basic eye examination and assessed best-corrected vision acuity (BCVA) and provided VR services. Furthermore, two schools were selected to establish an ATVI learning center as a pilot model.
Results:
In total, 1887 students were registered for VR and obtained their disability certificates in 2019-20. Retina problems (25.7%), globe abnormalities (25.5%), optic nerve atrophy (13.6%), and squint (12.0%) were common ocular problems identified in students. Around 50.3% of students had BCVA ³ 1/60 in the better eye who would be benefited from visual-based AT, and the remaining students with visual substitution AT. Further, 20.8% of them who had near vision between N18 to N24 would be benefitted from large print books. Two schools were provided ATVI with support from the WHO. Familiarization, demonstration, and initial training for ATVI were carried out.
Conclusion:
A sizable number of the students would be benefitted from visual-based AT apart from visual substitutions AT. Students were interested to have such ATVI centers in the school for academic and non-academic skills development.
Keywords: Assistive technology for visual impairment, schools for the blind, students with visual disabilities, training for assistive devices
Globally, more than 1 billion people live with some form of disability.[1] A significant proportion of them (90%) are from low- and middle-income countries (LMICs). This number is expected to double by 2030 as a result of an aging population and chronic debilitating diseases. Persons with visual disabilities constitute a substantial proportion of the total pool of disabilities. In India, there are about 53 million people with vision impairment, including 6.8 million with blindness (WHO 2010). A recent National Blindness Survey in India (2015-19) reported that nearly 80 million people across all age groups have a visual impairment, including blindness.[2,3] It is estimated that around 8,00,000 children have low vision or blindness in India. Furthermore, a population-based study among children in Delhi showed that the prevalence of visual impairment was 6 per 1000 children and 0.42 per 1000 for blindness.[4]
Access to good-quality and affordable assistive technologies is one of the key components of the UN Convention on the Right of Persons with Disabilities.[5] In the context of eye health, one of the key functions of the Universal Eye Health Coverage of the World Health Organization (WHO) is the provision of rehabilitative care and appropriate assistive health technology among people with visual disabilities.[6] At the heart of Sustainable Development Goals (SDG), the pledge is that “no one should be left behind.”[7] The 71st World Health Assembly resolution urged that the inclusion of AT, in line with countries’ national priority and context, and integration into the health systems is essential.[8] The WHO has also come out with a generic Assistive Products Priority List (WHO, APL) which has a number of such assistive products.[9] A new landmark resolution EB148.R6 titled “The highest attainable standard of health for persons with disabilities” was adopted by the 74th World Health Assembly, reiterating the WHO’s commitment to the area.[10] Children with disabilities encounter many inequalities as compared to children without disabilities, especially in education.[11] Therefore, augmenting children with visual impairment or blindness from an early age with the use of AT is critically important. Schools for the blind are the place where children—both with low vision and blindness—learn and develop many academic and non-academic skills, improve their self-esteem, social connection, and cognitive functioning, and prepare themselves for later employment and productive life. Thus, schools for the blind are ideal settings for such AT for VI intervention programs.
Evidence exists that assistive technology for visual impairment (ATVI) is one of the very important ways to improve independent living skills and maximize students’ educational potential. Many studies across the world have shown that using assistive technologies improves and enhances academic skills such as fine and gross motor, reading and writing capacity, mathematics and science ability, and problem-solving skills among children with visual disabilities.[12–15] Additionally, assistive technologies help in orientation and mobility, social inclusion, self-esteem, autonomy, and independence in daily living activities.[16] Despite the well-known benefits of ATVI, studies in India have reported poor availability of ATVI in blind schools.[17] For example, a study reported that only Braille slate, stylus, and abacus were assistive devices available at most of the blind schools (>90%). The same study reported that 11 of 52 ATVIs included in the study were available in 60% of the blind schools in Delhi with few AT trainers in these schools.[18] A study on challenges in accessing AT in these schools has also reported that lack of availability in schools and economic constraints were the most frequent barriers faced by students.[19] Devising strategies to improve the services related to ATVI is paramount in these schools. Such an initiative will help to enhance not only academic skills but also non-academic skills.
The present study aimed to identify the types of ocular comorbidities present among blind students based on their disability certificates to develop a school-based model to improve AT access in two selected schools for the blind and provide hands-on training on their use. Such AT initiative models will help in enhancing education, daily activity performance, games and leisure activities, orientation, and mobility in students with vision loss. In addition, teachers, caregivers, and family members of students will become aware of available assistive devices and their benefits.
Methods
The national capital Delhi has a total of 25 schools for the blind where students with visual disabilities reside and study. As a part of the community-based vision rehabilitation (VR) program, the VR team of a tertiary eye-care institute comprising one resident ophthalmologist visited these schools to provide VR services and training to the students and teachers. During each visit, the students underwent visual acuity assessment, both distance-presenting and best-corrected visual acuity. In addition, their visual disability certificates were checked for clinical information and also assessed the usage of optical and non-optical assistive products.
The distance vision was assessed using Snellen’s E charts with 6/18 and 6/60 optotypes at various distances. The near vision was assessed at the best comfortable distance at which the participants performed most of their near work. The primary aim of these tests was to determine which type of AT for VI, whether visual-based or visual substitution based, would be useful for the participants. Furthermore, the team also conducted basic ocular examinations, such as lens examination and direct ophthalmoscopy, and a dilated refraction if required in the school itself. If a participant needed further evaluation, they were then referred to the base eye hospital. The integration of a basic eye examination has helped us to establish a better relationship, and cooperation and increase the participation of students and teachers.
The rehabilitation needs of the participant were assessed based on the community-based rehabilitation (CBR) matrix developed by the WHO. Participants were trained for orientation and mobility, appropriate daily living activities, including dining techniques, sensitization, and training on the use of optical magnifiers, other non-optical devices, and reading, and writing rehabilitation devices. In addition, they were informed about various government schemes for visual disabilities and suitable vocational training facilities.
We relied on the best-corrected visual acuity and ocular problems for the study as shown in the visual disability certificate because they were issued from the eye hospital. Almost all students either have recently issued or renewed visual disability certificates. The government of India revised the criteria for disability certification in 2018, and the same had been published in The Gazette of India.
Following the initial assessment, a list of common ATVI needed was compiled and the same was procured to establish “AT Experiences and Learning Zone” in two selected blind schools. The WHO supported the procurement of the required ATVI. Teachers play a fundamental role in the education of students with vision loss. It was decided teachers who were nominated from each school to be trained for ATVI. (AT list in Annexure-1) The involvement of the teachers was important to sustain the program in the long run. They may also train caregivers and family members on the use of ATVI in the future. There was no involvement of parents while providing AT training. However, all blind schools in Delhi are residential, so whenever parents come to the school, we encouraged teachers and staff for parents to orient and sensitize AT for visual impairment.
AT training
First, ATVI was categorized into two categories based on body sense to be used in learning and education.
Visual-based ATs (VATs): These are ATs that need visual skills for learning and educational purposes. These ATs can benefit students with binocular BCVA less than <6/18 to 1/60, for example, large print books, magnifiers, and typoscopes.
Tactile and sound-based ATs (TATs): These are ATs that need visual substitution skills for learning and educational purposes. These ATs can benefit students with binocular BCVA less than 1/60 to no light perception, for example, Braille books or keyboards, Digital Accessible Information System (DAISY) books, walking (long) cane, etc., They can also be termed haptic devices.
Furthermore, children with visual disabilities were categorized into two different triaged based on their BCVA as follows:
Group 1: Students with a binocular BCVA less than <6/18 to 1/60. They are potential beneficiaries of ATs based on visual skills such as optical aids or large print books. Group 2: Students with a binocular BCVA less than 1/60 to no light perception. They are potential beneficiaries of ATs based on visual substitution skills. Fig. 1 presents the protocol that was used for training purposes.
Figure 1.
Triage of students with vision loss based on the BCVA for AT training
AT trainers
For the current initiative, two groups of trainers are primarily involved to impart training to the students, viz.
Visual-based AT (VAT) trainers: This is to train the devices needed for visual skills to use them, e.g., magnifiers, typoscopes, electronic magnifiers, large print keyboards, and high-contrast keyboards.
Tactile and sound-based (TAT) trainers. This is to train the devices needed visual substantial skills to use them, e.g., walking cane, DAISY, sonic labeler, digital audio recorder, Victor readers, and so on.
Organization and resources
The current AT service initiative was launched in conjunction with resources from the schools and the project funder and implementing eye hospital. A dedicated vision rehabilitation team with a minimum of two staff is required for such an initiative with one supervisor. For the present initiative, one medical social worker and one data entry operator or someone well acquainted with smartphones and computers were AT trainers.
In our case, a single room with adequate space was allocated by the school authority. The necessary renovation of the room was performed by the school, whereas a few pieces of furniture as per requirement were purchased from the project funds. The school also provided free internet access. The majority of the assistive technologies were kindly supplied by the funding agency, though we also procured a few of them. To start such an initiative, approximately Rs. 4 lakhs was spent for a school to buy a few basic assistive devices, two computers and screen reader software, and a few pieces of furniture, excluding the cost of human resources.
Results
A total of 1942 students with visual disabilities were enumerated for visual rehabilitation by the low vision rehabilitation (LVR) team who studied in schools for the blind in Delhi. More than two-thirds of them were male students. About 42.5% of them were of the age group 15 to 19 years, followed by 33.8%, 20.1%, and 3.6% of age groups 10 to 14 years, 5 to 9 years, and less than or equal to 4 years, respectively [Table 1].
Table 1.
Age and gender distribution of the study participants
| Age groups | Male (%) | Female (%) | Total (%) |
|---|---|---|---|
| ≤4 years | 46 (3.5) | 23 (3.6) | 69 (3.6) |
| 5-9 years | 258 (19.7) | 132 (20.8) | 390 (20.1) |
| 10-14 years | 452 (34.6) | 205 (32.3) | 657 (33.8) |
| 15-19 years | 552 (42.2) | 274 (43.2) | 826 (42.5) |
| Total | 1308 (67.4) | 634 (32.6) | 1942 |
From the enumerated students, the LVR team assessed 1887 (97.2%) students for distance visual acuity and 737 (37.9%) for near vision. Approximately, 50.3% of students had a best-corrected vision acuity (BCVA) better than 1/60 and 937 (49.7%) less than 1/60 in the better eye. [Table 2] Low vision, defined in the ICD classification as BCVA less than 6/18 to 3/60, was present in 769 (40.8%) students who were examined for distance vision. As far as near vision is concerned, out of the 737 students, 372 (50.5%) of them had greater than N 24, that is, they had better near vision than N 24. Of this, 20.8% of them had near vision between N18 and N24.
Table 2.
Distance and near BCVA of the students
| Right eye (%) | Left eye (%) | Better eye (%) | |
|---|---|---|---|
| Distance | |||
| <6/18 to 6/60 | 489 (25.9) | 485 (25.7) | 570 (30.2) |
| <6/60 to 3/60 | 186 (9.9) | 160 (8.5) | 199 (10.5) |
| <3/60 to 1/60 | 180 (9.5) | 203 (10.8) | 181 (9.6) |
| <1/60 to PL+ | 662 (35.1) | 671 (35.6) | 648 (34.4) |
| PL- | 370 (19.6) | 368 (19.5) | 289 (15.3) |
| Total | 1887 (67.4) | 1887 | 1887 |
| Near Vision | |||
| >N18 | 180 (24.4) | 165 (22.4) | 219 (29.7) |
| N18 to N 24 | 127 (17.2) | 127 (17.2) | 153 (20.8) |
| <N24 | 430 (58.4) | 445 (46.1) | 268 (49.6) |
| Total | 737 | 737 | 737 |
The most common ocular morbidities identified among the study participants were retinal diseases (25.7%) and globe abnormalities (25.5%), followed by optic atrophy (13.6%), squint (12.0%), and corneal diseases (9.5%). [Table 3]. Other less frequent ocular morbidities were glaucoma (4.3%), cataract (3.1%), and trauma (0.3%).
Table 3.
Ocular morbidities in students in schools for the blind (as in certificate)
| Diagnosis | Blind (%) | Low Vision (%) | Number (%) |
|---|---|---|---|
| Corneal diseases/corneal opacity/CHED | 119 (10.6) | 60 (7.8) | 179 (9.5) |
| Cataract/pseudophakia/aphakia | 37 (3.3) | 22 (2.9) | 59 (3.1) |
| Optic atrophy/hypoplasia | 165 (14.8) | 91 (11.8) | 256 (13.6) |
| Retinal detachment/RP/HMD/RCD/CMD | 223 (19.9) | 262 (34.1) | 485 (25.7) |
| Glaucoma/Congenital glaucoma | 53 (4.7) | 29 (3.8) | 82 (4.3) |
| Globe abnormalities/Phthisis/Microphthalmos/Coloboma | 340 (30.4) | 141 (18.3) | 481 (25.5) |
| Trauma/Injury | 3 (0.3) | 2 (0.3) | 5 (0.3) |
| Nystagmus/Squint/Exotropia | 123 (11.0) | 104 (13.5) | 234 (12.0) |
| Cannot accessed | 55 (5.0) | 58 (7.6) | 113 (6.0) |
| Total | 1118 | 769 | 1887 |
CHED: Congenital hereditary endothelial dystrophy, RP: retinitis pigmentosa, HMD: hereditary macular degeneration, RCD: rod and cone dystrophy, CMD: cystoid macular edema
However, among students with blindness, globe abnormalities (30.4%) were the most common ocular disorder, followed by retinal diseases (19.9%), optic atrophy (14.8%), squint (11.0%), and corneal diseases (10.6%). Among students with low vision, retinal diseases (34.1%) were the most frequently found eye problems, followed by globe abnormalities (18.3%) and squint (13.5%).
AT experience center
“AT Experiences and Learning Centres” were established in two selected schools after due consultation with school authorities. The name of the center was designed as per students’ suggestions. The school authorities were informed about the purpose of establishing such a center in the schools. The LVR team consulted with students and special educators before establishing the centers. The trainers from the base of the hospital included both digital and non-digital trainers. The participants were oriented and trained about ATVI in a batchwise manner, starting from higher to lower classes. To sustain the AT training program after the end of the project, training was imparted to the nominated teachers as well. After the induction AT training, refresher training for teachers was also provided on a periodic basis so that they could continue the ATVI training. The various training methods being provided were reading, writing, orientation and mobility, activities of daily living, currency identification, dining techniques, and use of smartphone-accessible features and apps. However, performance improvement and the impact of the ATVI training were not measured in the current study.
Discussion
Visual disabilities can severely affect educational and academic activities and can hamper employment opportunities in the later years of life. A study reported that the illiteracy rate among visually challenged children is approximately 80% in India.[20] Special schools for the blind are a separate system of an academic institution outside the mainstream education system. Such schools are required to have resources that are not readily accessible in mainstream schools. Students studying in these schools need to be trained regarding ATVI and empowered with proper education from the very beginning so that they can use AT for their future development and employment. The current study will help to fill this gap by establishing an AT experience center and imparting training regarding ATVI. Such an AT initiative will help in addressing the AT need, and therefore, schools for the blind are the ideal place because students spend a considerable time there.
The AT experience and learning centers were established in two schools for the blind for enabling students to learn about ATVI, including newer assistive devices. The centers also helped in enhancing the skills and knowledge of the special teachers. For training purposes, children with visual disabilities were categorized into two different groups: those with a BCVA less than 1/60 (group-1) and those with a BCVA better than or equal to 1/60 (group-2). At the same time, ATVIs were also categorized as visual-based AT (VAT), which can be used productively by group-1 students, and tactile and sound-based AT (TAT) for group-2 students. Such categorizations were also reported in other studies.[21]
The present study also showed that approximately 50% of students would be benefited from visual-based AT, such as electronic and optical magnifiers. Schools for the blind need to be equipped with VAT in addition to traditional Braille methods of teaching. Besides this, around half of the students who had a near vision better than N24 will be benefited from large print book materials. A print size beyond N 24 will not be feasible both practically and economically.
There are numerous studies that documented that the use of ATVI enhances performance and skills in handwriting, reading, and writing capacity and mathematics, science, and problem-solving among students with visual disabilities and also leads to substantial improvement in non-academic skills, such as social inclusion, communication, self-esteem, etc. [13,22,23] In the current study, the impact of ATVI training could not be measured due to the COVID-19 pandemic followed by the emergency lockdown and closure of all schools. However, it is recommended to conduct further studies and follow up in the future to evaluate the improvement, capturing various dimensions relating to ATVI training.
It is estimated that in developing countries, only 10% of blind children attend schools for the blind and females have still lower school enrollment than males.[24] The current study also demonstrated that females have lesser enrollment (32.6%) compared to males. Childhood blindness is an area of concern for all national and international efforts, especially in LMICs like India.[4]
Furthermore, the study also showed that nearly three-quarters of ocular morbidities are due to preventable eye diseases, such as corneal disorders, cataract, glaucoma, retinal disease or detachment, etc. Retinal detachment could be one of the sequelae of retinopathy of prematurity, which is showing a rising prevalence over the years.[25] In such a situation, it is important to provide comprehensive eye-care services to tackle childhood blindness across the country. The WHO estimates that there were 253 million people with visual impairment, including 36 million people blind globally in 2015, based on a study published in 2017.[26] Though the overall prevalence of blindness and visual impairment is much lower in children compared to adults, children need overarching attention because of the number of years that they must live with vision loss. Therefore, ensuring access to ATVI among students is essential for their academic and non-academic development. Establishing such centers in schools for the blind will help to address the challenge faced by students to a great extent.
Limitations
The current school-based initiative could not assess the improvement in the performance of various activities related to AT training. Following the COVID-19 pandemic, all schools were closed, and all students left their schools for their homes during the nationwide lockdown. Therefore, further study can be planned to evaluate the skill development and performance of students after ATVI training. The ocular morbidities of students were identified by relying on the visual disability certificates, as a result of which accurate reports on the causes of visual loss among children could not be identified; for example, squint was reported to be a major cause of visual loss in the results. The possible cause can be sensory deficit squint, but we could not establish it as a primary cause. The etiology perhaps has a potential role in the use of VAT and its adoption as well. The most important limitation is the selective selection of ATVI, and not all ATVI could be procured from the WHO. The more expensive ATVIs are also not suitable for LMICs as far as the sustainability of the present initiative is concerned.
Conclusion
In the present pedagogy of schools for the blind, there is a large range of AT for students with visual impairment available. It is important to ensure that all students are able to access to appropriate AT they need for their academic and non-academic skill learning. Such an initiative in schools will help address the scarcity of assistive technology and poor exposure to modern AT among special teachers and students. Furthermore, the model will help to provide evidence for advocacy in the future. Researchers, academicians, eye-care professionals, and rehabilitationists may design similar initiatives and thereby generate evidence of a successful model for advocacy.
Financial support and sponsorship
The WHO, Southeast Asia, supports the provision of assistive devices for visually impaired, while Christoffel Blinden Mission, International for the Manpower.
Conflicts of interest
There are no conflicts of interest.
Annexure 1: List (not all) of ATVIs for training
Technologies for reading and writing
1. Large print books: Individuals with low vision have difficulty reading small and usual print-size text (N 6–8). Large-size print text (N 18 to <N 24) with a font size of 16–18 helps in reading.
2. Typoscope: It can be used for either a reading guide (one window) or a writing guide (multiple windows) according to the design being made. For example, a single-window typoscope is useful for albinism individuals in reading.
3. Reading stands: Book or reading stands are meant for display that help to reduce the physical stress or fatigue experienced by readers with low vision. It helps in avoiding bending over the surfaces to view text. It also helps Braille readers.
4. Low vision lamps: Enhance lighting may help students with low vision to read easier, thereby improving their reading performance.
5. Optical magnifiers: Optical magnifiers (near and distance), for example, hand-held magnifiers, dome, stand and pocket magnifiers, and telescopes are task-specific optical aids that enlarge the image formed on the retina.
6. Electronic Magnification Aids (EMAs): Electronic magnifiers are usually termed electronic vision enhancement systems (EVESs). For example, hand-held video magnifiers.
7. Refreshable Braille Display (RBD): RBD works with a screen reader and enables the user to read what is on the computer screen by touching a Braille display. A Braille display has different sizes from 12 to 80 Braille cells, each cell has six or eight pins which are connected electronically to the computer to be able to move up and down when typed on Perkins style keypad and to display a Braille version of characters on the computer screen.
8. Audio Format Materials (AFMs): AFM is beneficial for many students with low vision and blind. It enables students to read or access information through hearing, for example, the DAISY (Victor Reader).
9. Screen Reader Software: This software allows people or students with low vision and blind to convert text on a computer screen and in documents to synthetic speech, that is, audio output as well as keystrokes entered on the keyboard, and navigational information. Screen readers require the use of keyboard shortcuts, for which the user must memorize most of the keys. Many screen readers work with multiple programs, but some screen readers are specific to certain programs, for example, JAWS and NVDA
10. Braille typewriter (Perkins Brailler): It is a portable low-tech writing tool with six keys corresponding to each of the six Braille dots. There are many models of the Perkins Brailler that suit according to the needs.
11. Large computer keyboards: This is a keyboard with a 2.5 M notation print size.
12. Digital audio recorder: The non-displayed digital recorders are specially designed for persons with visual impairments, for example, PlexTalk.
AT for orientation and mobility
1. Walking or long cane: It is designed primarily as a mobility tool used to identify objects in the path of the users. The length of the cane depends upon the height of the user, and usually, it extends from the floor up to between the sternum and under the chin when standing upright.
2. Children's cane: This cane works the same as a long walking cane but is designated for use by children.
3. Symbol or identification canes: A symbol cane is primarily used to notify the general public that the person has a visual impairment or low vision. It is often shorter and lighter than others. It intends not to be used as a body support or to detect obstacles on the floor or as a mobility tool. Red-and-white-colored banded symbol canes highlight both a visual and hearing impairment. This will be used if the person has a residual visual function left.
4. Guide canes: This is a shorter and thinner cane but longer than guide cane usually extending from the floor to the user's waist when standing upright with more limited mobility function. The guide cane is used to scan for kerbs and steps. It can be used diagonally across the body for protection and to warn the user of obstacles immediately ahead.
AT for Activities of Daily Living
1. Sonic labeler: This electronic pen-like device is used for the purpose of identifying objects using a label attached to the surface of the objects.
2. Talking watch or alarm clock: This talking device clearly announces the time and can be used for an alarm.
3. Talking oximeter: A talking oximeter for persons with visual impairment which measures blood oxygen saturation (% SpO2) and pulse rate.
4. Pill organizer: This device is particularly useful for low vision or blind individuals who need to consume multiple medications every day. It has a separate compartment for pills taken at different times of the day. Color-coded lids or Braille-marking boxes are available.
5. Mobile Applications: Smartphone accessibility has increased significantly in recent years. Specialized accessibility applications (screen reading or screen magnification software) that work on smartphones and tablets are used. Many mobile applications will have in-built accessibility features such as optical character recognition (OCR), object recognition, the global positioning system (GPS), and route finding (for example, Be My Eyes, TapTapSee, etc.)
Head-Mounted Display Devices
1. AceSight: Electronic glasses employ Augmented Reality (AR) technology and feature two full HD displays that float in front of each eye with 8 megapixel and 45-degree field of view per eye. A hand-held controller allows the user to adjust magnification, colors and contrast, and enhancement of the edge of the object.
2. eSight: eSight refers to wearable smart glasses that help people suffering from central vision loss.
3. Oxight Onyx: A smart glass and wearable technology designed for people with peripheral vision impairment.
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