|Year : 2016 | Volume
| Issue : 2 | Page : 35-42
School-based hearing screening program in children, four to seven years old, Quesnay City, Minufia, Egypt
Radwa Mahmoud PhD 1, Mohammed Ibrahim Shabana2, Ahmed Mohsen Seleit3, Ahmed Ashraf Salah El-hamshary3, Noha Ali Hosni4
1 ENT Department, Audiology Unit, Banha University, Banha, Egypt
2 Professor of Audiology, Faculty of Medicine, Cairo University, Cairo, Egypt
3 Professor of Otorhinolaryngology, Faculty of Medicine, Benha University, Banha, Egypt
4 Assistant Professor of Audiology, Faculty of Medicine, Cairo University, Cairo, Egypt
|Date of Submission||30-Nov-2016|
|Date of Acceptance||30-Nov-2016|
|Date of Web Publication||20-Mar-2017|
ENT Department, Audiology Unit, Banha University, Banha
Source of Support: None, Conflict of Interest: None
Hearing is the most essential perceptive sense for individual development, especially during childhood, contributing to a child’s ability to interact with other people. Its deprivation can have serious consequences on various aspects, such as speech and language acquisition and prereading skills. This study aimed to perform hearing screening of school children aged 4 and 7 years to detect the prevalence, incidence, and degree of hearing loss (HL) in this age group.
Participants and methods
This study was a cross-sectional investigation that included all children aged 4–7 years from all primary schools in Quesnay City, Minufiyah governorate, Egypt, from November 2014 to March 2016 (number of children=4500). A total number of 9000 ears were studied. All children included in the study underwent otoscopic examination, followed by two stages of school-based hearing screening. All children who failed the second stage of school-based hearing rescreening were referred for full audiological evaluation.
Otoscopic examinations revealed the following: 54.2% of ears had normal ears 21.3% had impacted wax, 13.6% had congested tm, and 10.8% had perforated tm. Twenty percent (1800 ears) failed the first stage of school-based hearing screening. Six percent (540 ears) failed the second stage of school-based hearing rescreening. A total of 529 ears were diagnosed as having HL as follows: 427 (80.7%) had conductive hearing loss, 81 (15.3%) had sensorineural hearing loss, and 21 (4%) had mixed HL of different degrees − 265 (50.1%) had mild, 132 (24.9%) had moderate, 85 (16.1%) had moderately severe, 40 (7.6%) had severe, and seven (1.3%) had profound degree of HL.
A systematic screening program with correct equipment, trained personnel, and adequate follow-up services will allow children with educationally significant HL to be accurately diagnosed and managed to provide them with equal hearing opportunities.
Keywords: hearing screening, school children, otoscopic examination
|How to cite this article:|
Mahmoud R, Shabana MI, Seleit AM, Salah El-hamshary AA, Hosni NA. School-based hearing screening program in children, four to seven years old, Quesnay City, Minufia, Egypt. Adv Arab Acad Audio-Vestibul J 2016;3:35-42
|How to cite this URL:|
Mahmoud R, Shabana MI, Seleit AM, Salah El-hamshary AA, Hosni NA. School-based hearing screening program in children, four to seven years old, Quesnay City, Minufia, Egypt. Adv Arab Acad Audio-Vestibul J [serial online] 2016 [cited 2017 Aug 18];3:35-42. Available from: http://www.aaj.eg.net/text.asp?2016/3/2/35/202553
| Introduction|| |
Our ability to hear is orchestrated by the auditory system. However, the vestibular system is responsible for balance, three-dimensional orientation, and gravity perception . The three chambers of the ear are essential for intact activity of both auditory and vestibular systems ,.
Partial or total inability to hear is known as hearing loss (HL), hard of hearing, anacusis, or hearing impairment. It may occur in one or both ears. In children hearing problems can affect the ability to learn language and in adults it can cause work-related difficulties . Deafness is typically used to refer to those with little or no hearing .
As HL is one of the most common birth defects, early diagnosis of the child’s HL can allow the monitoring of possible complications and can indicate which therapy is the most suitable and effective. It also allows for more accurate genetic counseling for parents who want to have more children .
HL is the most prevalent sensory impairment in both childhood and adulthood ,. According to the last update of the WHO , ∼360 million people worldwide, equaling 5% of the world’s population, have a disabling HL (328 million adults and 32 million children). Most of these people live in low-income and middle-income countries where treatments for HL are more difficult to obtain and consanguinity increases the risk of recessive disease.
In Egypt, there have been no national surveys on the prevalence of HL and deafness and there are few hospital-based academic studies that give an idea about the magnitude of the problem . No conclusive data or recommendations could be drawn from such limited studies in Egypt. Therefore, there is a need to conduct a study on a national level.
Causes of HL in children can be classified into HL at birth (congenital HL) and HL after birth (acquired HL). Congenital HL can be caused by genetic (herediatry) or nongenetic factors. Nongenetic factors account for about 25% of congenital HL. These factors that are known to cause congenital HL include the following: maternal infections such as rubella (German measles), cytomegalovirus, or herpes simplex virus; prematurity; low birth weight; birth injuries; toxins, including drugs and alcohol consumed by the mother; complications associated with the Rhesus (Rh) factor in the blood; maternal diabetes; toxemia during pregnancy; lack of O2 (anoxia); and genetic factors (hereditary). They are thought to cause more than 50% of all HL cases. HL from genetic defects can be present at birth or may develop later in life. Acquired HL may be the result of an illness or injury such as ear infections as otitis media (very common in children), medications that are toxic to the ear, meningitis, encephalitis, measles, chicken box, flu, mumps, head injury, and noise exposure .
Hereditary or genetic HL accounts for almost 50% of all congenital sensorineural hearing loss (SNHL) cases, and it is caused by genetic mutations . HL can be the result of a mutation in a single gene or a combination of mutations of different genes; it can also be a result of environmental causes such as trauma, medications, medical problems, and environmental exposure, or the result of an association between environmental factors and genetic factors . HL can be either nonsyndromic, which is restricted to the inner ear, or syndromic, a part of multiple anomalies affecting the body .
Prematurity and low birth weight infants: WHO defines prematurity as babies born before 37 weeks from the first day of the last menstrual period. Recent data indicate that more than one in 10 babies born worldwide in 2010 were premature and this translates into an estimated 15 million preterm births . SNHL is found in a small proportion of very preterm survivors, but prematurity is a commonly quoted risk factor for acquired HL. In various very low birth weight or preterm populations, the prevalence of high-frequency HL among survivors is 0–4%, about 10 times the incidence in an unselected population ,.
Hyperbilirubinemia can cause selective damage to the brainstem auditory nuclei and may also damage the auditory nerve and spiral ganglion cells. It does this by interfering with neuronal intracellular calcium homoeostasis. In contrast, the organ of corti and thalamocortical auditory pathways appear to be unaffected by bilirubin. Clinically, a common form of HL caused by hyperbilirubinemia is auditory neuropathy. Thus, otoacoustic emissions screening is normal but auditory brainstem response testing is abnormal .
Hypoxia also has a strong association with HL. Adequate oxygenation and perfusion are essential for normal cochlear function ,. In newborn infants with hypoxia or asphyxia, the spiral ganglion cells appear to be affected first .
Aminoglycosides can be the best or only choice of antibiotic for certain infections. Unfortunately, they also damage both the cochlear and vestibular organs, although they typically affect one more than the other. The two preferentially vestibulotoxic agents are gentamicin (the most widely used) and tobramycin. Aminoglycosides that are more selective to the cochlea are neomycin, kanamycin, and amikacin. These agents produce irreversible hearing loss by causing hair cell death .
Persistent middle ear fluid from otitis media with effusion (OME) results in decreased mobility of the tympanic membrane (TM) and serves as a barrier to sound conduction. At least 25% of OME episodes persist for 3 months or more , and may be associated with HL, balance (vestibular) problems, poor school performance, behavioral problems, ear discomfort, and recurrent acute otitis media . Less often, OME may cause structural damage to the TM, requiring surgical intervention . The impact of OME on hearing ranges from normal hearing to moderate hearing loss (0–55 dB HL) , ([Figure 1]).
|Figure 1 An average hearing level between 0 and 20 dB is normal (green), 21–40 indicates mild hearing loss (yellow), 41–60 indicates moderate loss (red), and 61 dB or higher indicates severe loss (purple). A child with average hearing loss from middle ear effusion in both ears (28 dB) will barely be able to hear soft speech, with some children barely aware of normal speech or a baby crying .|
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HL has negative impacts on child development, such as social–emotional development (SED). Previous research has indicated that children with HL may face unique difficulties with mastering SED. Although the prevalence of such problems is unknown, some reports suggest that difficulty with SED may range from 8  to 41.3% . The underlying causes of such SED may be linked to communication challenges and potential language delays that often occur in children with HL .
Specifically, HL can negatively affect a person’s ability to communicate with others, thereby impacting the quality of social interactions. It is not surprising that SED challenges can occur in children with HL given that language is a social tool that individuals use to communicate with others. Furthermore, if the listening environment is poor or if children are unable to adequately recognize an auditory signal then minimal interaction between students with HL and normal-hearing peers is likely .
Additionally, even if students do hear the auditory message, they still may not understand the linguistic nature of the signal, thus further limiting the opportunity for appropriate interactions to occur. Some research has suggested that preschoolers with HL have greater difficulty maintaining attention and thus are unable to sustain interactions long enough for a social exchange to take place .
This reduced interaction may also be due to inappropriate pragmatic uses by persons with HL, decreased perception of emotion, inadequate strategies to gain access to a group, or multiple failed communication initiations ,,,. Regardless of the precise underlying cause of reduced interactions, children with HL would appear to be at risk for SED issues .
HL has also negative impacts on language development. The impact of HL on the early development of a child’s language and cognitive skills can be pervasive. When a child has a hearing impairment of early onset, even of a relatively mild degree, the development of these skills is often delayed. Such delays adversely affect communicative and academic success .
Regardless of the type of HL, the development of auditory skills that are a prerequisite to the development of receptive and expressive language skills, as well as speech intelligibility, is delayed. Such auditory skills include detection, discrimination, recognition, comprehension, and attention. In turn, a delay in the early development of auditory skills caused by a HL negatively impacts a child’s ability to learn and use an auditory–oral language system .
To best serve the needs of a child with hearing impairment, all persons who provide services to the child should work as a team. This team includes the child’s parents, primary care physicians, audiologists, educators, and speech–language pathologists. After the members of an assessment team determine the impact of the child’s hearing loss in various domains, the focus of intervention should be to provide optimal support services to the child. The team should also commit to long-term monitoring to assess the effects of the hearing impairment on academic achievement and the effectiveness of the intervention plan .
The aim of the study was to perform hearing screening of school children between the ages of 4 and 7 years in Quesnay City, Minufiyah, Egypt, and to detect the prevalence, incidence, and degree of hearing loss in this age group.
| Participants and methods|| |
Study design and sample size
This was a cross-sectional study carried out over 17 months from November 2014 to March 2016 and included all children (boys and girls) 4–7 years old from all primary schools (five public and three private) in Quesnay City, Minufiyah governorate, Egypt, from November 2014 to April 2015.
This study was undertaken after taking written consent from the educational administration in Quesnay City.
All children aged 4–7 years from all primary schools of Quesnay City, Minufiyah governorate, Egypt, were eligible to participate in this study, which was conducted from November 2014 to April 2015.
Technique and equipment
Personal history (school type, age, sex, area of residence, level of education of parents) of each child was registered. Otoscopic examination of both ears of each child was performed using a Richter otoscope.
School-based hearing screening was performed in two stages as follows:
Screening was carried out in an acoustically appropriate environment (the most quite room in the school, such as the room of the social specialist). Biological check on the pure-tone screening equipment (one-channel audiometer, model 26; Amplivox: 6 Oasis Park, Eynsham, Oxfordshire, OX29 4TP, United Kingdom) was done every day before starting the screening.
Pure-tone sweep at 1000, 2000, and 4000 Hz (air conduction only) at 20 dB HL was presented to each ear separately. Each tone was presented at least twice but no more than four times if the child failed to respond.
Lack of response at any frequency in either ear at 20 dB HL for frequencies 1000, 2000, and 40000 Hz constituted a failure. Such children underwent immediate rescreening in the same session after reinstructing the child and repositioning earphones.
Children who failed pure-tone immediate rescreening underwent tympanometry (Immittancemetry, model AZ26; Interacoustic: 5500 Middlefart, Denmark) in the Hospital of Banha University. Static admittance flat or less than 0.2 mmhos was considered a failure criterion.
Children who failed tympanometry underwent rescreening after 8–10 weeks (second stage of school-based hearing screening).
Children who passed tympanometry were divided into two groups (children who failed school-based hearing screening in one frequency in one or both ears were added to the group that failed tympanometry and they underwent rescreening after 8–10 weeks; children who failed school-based hearing screening in two or more frequencies in one or both ears were referred to Hospital of Banha University for full audiological evaluation by pure-tone audiometry (one-channel audiometer, model TA 156; Hanston: 14755 27th Ave North, Plymouth, MN 55447, USA) or evoked potential one-channel auditory brainstem response (Biologic Pro navigator: Interacoustic products).
Children who failed rescreening after 8–10 weeks (second stage of screening) were referred to Hospital of Banha University for full audiological evaluation by pure-tone audiometry or auditory brainstem response.
This method of school-based hearing screening was based on guidelines of screening recommended by American Academy of Audiology, 2011.
All statistical analyses were conducted using SPSS statistical package for windows, version 18. The results were presented in simple charts and tables as appropriate. Differences between categorical variables were explored using the χ2-test with statistical significance set at P less than 0.05.
| Results|| |
The study included all children aged 4–8 years in primary schools of Quesnay City, Minufiyah governorate, Egypt, from November 2014 to April 2015. There were about 4500 (100%) children distributed between public and private schools: 1000 (22.2%) children in private schools and 3500 (77.8%) in public ones.
The ages of children included in the study were between 4 and 7 years: 820 (18.2%) children were around 4 years old, 1080 (24%) children were around 5 years old, 1084 (24.1%) children were around 6 years old, and 1516 (33.7%) children were around 7 years old. The children included in the study consisted of 2228 (49.5%) boys and 2272 (50.5%) girls.
The study included the level of education of children’s mothers, which was divided into three categories: high level of education [1485 (33%) children], mid level [2115 (47%)], and low level [900 (20%)]. With regard to residence of the children, 414 (9.2%) children lived in rural areas and 4086 (90.8%) lived in urban areas.
A total of 4500 children were included in this study, totalling 9000 ears. These 9000 ears underwent otoscopic examination with results as follows: 4881 (54.2%) ears had normal ears 1914 (21.3%) ears had impacted wax whether occluding or not, 1228 (13.6%) ears had congested tm, and 977 (10.8%) ears had perforated tm ([Figure 2]).
After otoscopic examination, all children included in the study underwent the first stage of school-based hearing screening: 6120 (68%) ears passed and 2880 (32%) ears failed. Immediate rescreening was done on the 2880 ears that failed the initial screening: 1080 ears passed and 1800 ears failed. Thus, the net result of the first stage of school-based hearing screening was as follows: 7200 (80%) ears passed and 1800 (20%) ears failed ([Table 1]).
|Table 1 The net result of initial and immediate rescreening in the first stage of school-based hearing screening|
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There was no significant difference as regards the results of the first stage of school-based hearing screening between public and private schools: 79.4% passed and 20.6% failed in public schools, and 82% passed and 18% failed in private schools. There was also no significant difference in results between boys and girls: 80.3% of boys passed and 19.7% failed, and 79.7% of girls passed and 20.3% failed.
There was a slight difference in the results of the first stage of school-based hearing screening according to residence of the children: 80.5% of children who lived in urban areas passed and 19.5% failed, and 75.4% of children who lived in rural areas passed and 18% failed.
However, there was significant difference in the results of first stage of school-based hearing screening according to the level of education of mothers of the children: 84.8% of children with mothers having high level of education passed and 15.2% failed, 78.7% of children with mothers having mid level of education passed and 21.3% failed, and 75% of children with mothers having low level of education passed and 25% failed. There was decrease in failure rate with increasing level of education of mothers.
There was also significant difference in the results of the first stage of school-based hearing screening according to age: 74.6% of children around 4 years old passed and 25.4% failed, 79% of children around 5 years old passed and 21% failed, 80.6% of children around 6 years old passed and 19.4% failed, and 83.2% of children around 7 years old passed and 16.8% failed. There was decrease in failure rate with increasing age of the children.
Results of the first stage of school-based hearing screening in relation to otoscopic examination findings in 9000 ears included in the study were as follows: 99.6% of ears with normal otoscopic examination passed and 0.4% failed, 56% of ears with impacted wax passed and 44% failed, 58% of ears with congested tm passed and 42% failed, and 57% of ears with perforated tm passed and 43% failed.
All children who failed the first stage of school-based hearing screening (1800 ears) underwent tympanometry with results as follows: 15 (0.83%) ears passed and 1785 (99.17%) ears failed.
Ears that failed tympanometry (1785) underwent the second stage of school-based hearing screening after 8–10 weeks.
Ears that passed tympanometry (15) were classified into two categories: one of them included ears that passed tympanometry but failed one frequency in one or both ears (nine ears); this category underwent the second stage of school-based hearing screening after 8–10 weeks. The other category included ears that passed tympanometry and failed two or more frequencies in one or both ears (six ears); this category was referred to Hospital of Banha University for full audiological evaluation, which revealed normal hearing in these ears.
After 8–10 weeks, 1794 ears underwent the second stage of school-based hearing screening with results as follows: 1254 ears passed and 540 ears failed. Thus, the net result of the two stages of school-based hearing screening was as follows: 8460 (94%) ears passed and 540 (6%) ears failed ([Figure 3]).
|Figure 3 Results after the two stages of school-based hearing screening.|
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The 540 ears that failed the two stages of school-based hearing screening were referred to Hospital of Banha University for full audiological evaluation, with results as follows: 11 (2%) ears revealed normal hearing and 529 (98%) ears had hearing loss with different degrees and types.
Degrees of HL in the 529 ears were as follows: 265 (50.1%) ears had mild degree (from 26–40 dB HL), 132 (25%) ears had moderate degree (from 41 to 55 dB HL), 85 (16%) ears had moderately severe degree (from 56 to 70 dB HL), 40 (7.5%) ears had severe degree (from 71 to 90 dB HL), and seven (1.5%) ears had profound degree of HL (>91 dB HL).
The 529 ears with hearing loss were classified according to type of hearing loss into 427 (81%) ears that had conductive hearing loss (causes of HL in external ear or middle ear), 81 (15.3%) ears that had SNHL (causes of HL in inner ear or auditory nerve), and 21 (3.7%) ears that had mixed hearing loss (cause of HL combination of disease in external or middle ear and inner ear) ([Table 2]).
| Discussion|| |
Although hearing screening programs for neonates are reliably good, they have the limitation of missing out children with delayed-onset HL and also those with acquired causes (Lu et al., 2011), which are more common in developing countries (Rao et al., 2002; Afolabi et al., 2012). This study attempted to perform hearing screening of Egyptian school-aged children in Quesnay city, Minufiyah governorate.
Minufiyah is an Egyptian governorate that lies to the north of Cairo (capital of Egypt). The total population of Minufiyah was 3 270 404 persons according to the last statistics in 2007. Its area reaches 2 543 03 km2. Minufiyah is ranked eleventh on the basis of living standards. Quesnay City lies 60 km north of Cairo, bound from the north by Berket El-Sab3 City, from the south by El-Bagour City, from the east by Benha City (Qulubia), and from the west by Shebin El-Kom City. Its area is about 205.8 km2 and its population is about 54 047 persons.
The period of our study was about 17 months, similar to the period of study of Al-Rowaily et al. (2012)  in Riyadh city, Saudia Arabia, which covered 20 months (from March 2009 to December 2010). However, the period of our study was longer compared with that of the study by Sobhy (1998)  conducted in Alexandria city, Egypt, which spanned the educational years 1997–1998. The period of our study was also longer than that of Adebola et al. (2013)  conducted in Ogbomoso, Nigeria, which spanned 3 months (from June to August 2012).
The number of schools included in our study was similar to the number of schools included in the study by Adebola et al. (2013) , which was a cross-sectional study of preschool children from three public and three private primary schools. Seven schools were selected in the study performed by Olusanya et al. (2000) . Asmail et al. (2016)  included children from five public schools. Al-Rowaily et al. (2012)  included all children who attended the obligatory health examination for kindergarten and primary school entry in their study.
The number of children included in our study was larger than the number included in the study by Al-Rowaily et al. (2012) , which included 2574 children (1073 boys and 1501 girls), in the study by Lyn et al. (1998) , which included 2202 children (1047 boys and 1155 girls aged 5–7 years, with a mean of 6 years), in that by Adebola et al. (2013) , which included 101 children (55 boys and 46 girls, aged 3.5–6 years, with mean age of 4.8 years), by Olusanya et al. (2000) , which included 359 children (aged 4.5–10.9 years, with a mean of 6.7 years), by Basañez et al. (2015) , which included 639 children (aged 5–14 years, with a mean age of 9.5 years), and by Asmail et al. (2016) , which included 472 children (aged 5–10 years) in two phases.
A total of 4500 children were included in this study, totalling 9000 ears. All these ears underwent otoscopic examination using richter otoscope with results as follows: (i) normal TM was found in 4881 (54.2%) ears, (ii) impacted wax whether occluding or not was found in 1914 (21.3%) ears, (iii) congested TM was found in 1228 (13.6%) ears, and (iv) perforated TM (which may be of any shape, size, or site according to etiology) was found in 977 (10.8%) ears.
The distribution of otoscopic examination results was similar to the results of the study conducted in Nigeria by Adebola et al. (2013) , with results as follows: normal findings in 106 (52.4%) ears, wax in 44 (21.8%) ears, OME in 28 (13.9%) ears, and perforated TM in 24 (11.9%) ears. The similarity between the results of the two studies may be due to the fact that the studies included children with nearly the same age distribution between private and public schools.
Although the findings of otoscopic examinations were close to the results of Adebola et al. (2013) , which included schools in Ogbomoso, Nigeria, it differs slightly from another study conducted in Nigeria by Olusanya et al. (2000) . This study included 359 in schools from Lagos city in Nigeria. The ages of the children were between 4.5 and 10.9 years, with a mean age of 6.7 years. The results of the otoscopic examination were as follows: normal in 29.7%, wax accumulation in 52.6%, and middle ear abnormalities in 20.9%. There was difference between the studies in normal TM and impacted wax but the proportion was nearly the same for middle ear abnormalities in both studies.
The results of otoscopic examination in the South African study by Asmail et al. (2016) , which included children aged 6–12 years, were different from the results of our study as follows: normal ear canal and TM was found in 92.1%, wax was found in 6.6%, and other findings in 1.3%. The difference between the results of the two studies may be due to the difference in the age groups of children in the two studies.
The results of the first stage of school-based hearing screening were close to the results of Adebola et al. (2013) : 78.7% passed and 21.3% failed. This similarity between results was due to similarity in the characteristics of children, such as age, sex distribution, types of school included in both studies, and living conditions in both countries.
The results of the first stage of school-based hearing screening of our study were close to the results of Asmail et al. (2016) , with failure rate of 17%, when the failure criterion was considered to be greater than 20 dB HL, but higher than the results of Asmail et al. (2016) , with a failure rate of 6.7%, when the failure criterion was considered to be greater than 25 dB HL. As Asmail et al., 2016  considered in their study comparison of referral rates at different intensity levels of pure tone screening (20, 25, 30).
After 8–10 weeks, 1794 ears underwent the second stage of school-based hearing screening, with results as follows: 1254 ears passed and 540 ears failed. Thus, the total number of ears that passed school-based hearing screening in either stage increased to 8460 (94%) ears and the number of ears that failed the two stages of the study decreased to 540 (6%) ears. The result of rescreening after 8–10 weeks was close to that of rescreening after 8 weeks in the study by Adebola et al. (2013) , which was 4.5%.
| Conclusion|| |
A systematic screening program with correct equipment, trained personnel, and adequate follow-up services will allow children with educationally significant hearing loss to be accurately diagnosed and managed in order to provide them with equal hearing opportunities. Multiple steps for screening programs can significantly reduce the overall referral rate to avoid overburdening healthcare resources, especially in developing countries with limited healthcare services. Otoscopic examination remains a cheap diagnostic tool in audiological evaluation.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2]