intemattonal Journal ofPediatric Otorhinolaryngology, 24 (1002)1-Y 0 1992 Elsevier Science Publishers B.V. All rights reserved 016S-S876/92/%OS.O~)
PEDOT
00784
On criteria for hearing impairment in children Agnete
Parving and Birger Christensen
Department of Audiology, Bispehjerg Hospital, Copenhagen (Dettmark) (Received 4 June 1901) (Accepted 6 August 1991)
rCty words: Hearing-impaired/disabled
child; Criterion:
Parent/professional
Abstract As objective criteria concerning hearing impairment/ disability may be poorly related to the behavioral patterns of children with hearing deficits, the present investigation was performed. A consecutive series of 172 children, who were examined for the first time at the Audiological Department, was subdivided according to age into two groups: one comprising 98 children at an age from 49 to 84 months, the other comprising 74 children > 84 months of age. This second group is supposed to complain of hearing problems if present, and thus constitutes a reference group. Using the criterion for hearing impairment: BEHL 0.5-4 kHz > 20 dB HL, the data demonstrated that the frequency of correct and false positive suspicion (detection) of a hearing impairment is similar in parents and professionals with an observer sensitivity of 88%. In addition the frequency of suspicion in parents and professionals in relation to degree of hearing loss corresponds to the frequency of hearing problems, as experienced in the reference group of older children. A certain discrepancy exists between the applied criterion of BEHL 0.5-4 kHz > 20 dB and the hearing level resulting in deviating behavioral pattern or experienced hearing deficit in children. This may be ascribed to the predominantly conductive hearing loss in the examined sample. It is concluded that additional investigations on criteria for hearing impairment/ disability, including also children with sensorineural hearing loss should be undertaken.
Introduction
According to the World Health Organization (WHO) hearing impairment is defined as any loss or abnormality of psychological, physiological or anatomical Correspondenw NV. Denmark.
to: A. Parving,
Department
of Audiology,
Bispehjerg
Hospital,
DK 2400 Copenhagen
2
structure or function of hearing [19]. To make this definition operational a graded terminology has been included referring to degree of hearing loss (in dB hearing level) in the better hearing ear based on the average of speech frequencies (500, 1000, 2000 Hz). Thus hearing impairment is defined operationally as a hearing loss > 25 dB [19]. However, the importance of the frequency range above 2 kHz for the hearing ability has been emphasized, based on the results of laboratory as well as clinical investigations (see e.g. Refs. 1, 8, 15, 17 and 18). Consequently 4 kHz has been included into the ‘frequency criterion’ and used predominantly in epidemiological investigations [5,6,11]. However, it has been demonstrated in adults that the average of pure tone auditory thresholds at 0.5, 1, 2: 3, 4 kHz r 20 dB HL used as an objective criterion for hearing impairment and hearing disability appeared to be more relevant, when related to subjective hearing problems [12]. The diagnosis of hearing impairment assessed at a more or Iess arbitrary level of fence > 25 dB can be questioned, especially within pedoaudiology, where behavioral signs of hearing deficits are dominating in younger children (i.e. < 7 years of age). However, the advantages of worldwide agreement to uniform criteria and examination procedures for hearing impairment and disability are obvious, as pointed out by Davidson et al. [4]. Consequently a ‘criteria group’ was formed by the International Association of Physicians in Audiology (IAPA 1987) with the task to propose operational criteria for hearing impairment/ disability in children. Based on current knowledge the following operational criterion was recommended: a hearing impairment is present, if the better ear hearing threshold level averaged over the frequencies 0.5, 1, 2, and 4 kHz exceeds 20 dB HL (> 20 dB HL). In other words the hearing is considered to be ‘normal’, if the better hearing ear has an average 5 20 dB hearing threshold level. This change in averaged frequencies and in fence may have implications for future epidemiological investigations, but also for pass/fail criterion within hearing screening in childhood, and thus for the pedoaudiological services offered within the health sectors. However, an objective criterion based on an operational philosophy may be poorly related to the behavioral patterns found in children with hearing deficits [7], and may also differ between observers. Numerous investigations have demonstrated that the parents/family are the first to raise suspicion of a hearing loss in their child, both in sensorineural and conductive hearing disorders [2,10,13]. This investigation was performed in order to further examine the criterion of hearing impairment as it related to both non-professionals (parents/family) and professionals working with children.
Material
A total sample of 172 children (98 males, 74 females, at a median age of 79 months, range 49-205) were included into the investigation, according to the following criteria: their age should be 2 49 months, as the majority of children at this age are capable of performing play audiometry [14], and in addition the
Jot
20
0
49-54
55-60
61-66
67-12
73-78
79-84
1
nonths Fig.
I. Age
distribution
in the total
sample
of children.
years) are collected
All
the children
above
X4 months
of age (7
in one column.
examination should constitute their first audiological evaluation. The children were drawn from a consecutive series of 634 children, referred to and examined at the department during 1.5.89-1.5.90 for various reasons, predominantly problems related to hearing and speech disorders [16]. The age distribution at this first examination in these 172 children is shown in Fig. 1. Procedures
Information on all relevant aspects concerning diagnostic pedoaudiology was registered [16]. For the purpose of the present evaluation the following parameters were evaluated: suspicion/no suspicion present of a hearing deficit; who raised the suspicion: parents/family in contrast to professionals, i.e. general practitioners. ENT doctors, health visitors, pediatricians, staff at institutions (i.e. nursery or kindergarten), psychologists or speech therapists (special teachers); degree of hearing loss for the average of frequencies OS-4 kHz in the better hearing ear (BEHL OS-4 kHz). The suspicion of a hearing loss in younger children is raised by behavioral signs, observed by the parents or professionals or by complaints of a hearing problem in older children ( > 7 years). Thus the material was subdivided into two groups: one comprising 98 children (62 boys, 36 girls, between the age of 49 and 84 months), in whom behavioral signs had caused suspicion of a hearing loss; the second comprising 74 children (36 boys, 38 girls above the age of 84 months), acting as a control group, as the children at this age are anticipated to complain, if ear- or hearing problems are present. A comparison between the BEHL OS-4 kHz in the two groups of children below and above 84 months of age assured that no significant difference was present (Fig. 2).
Fig. 2. Degree of hearing loss in the group of children 5 84 months of age (open columns), and the children > 84 months’of age (hatched columns). Statistical analysis revealed no significant differences in the degree of hearing loss in these two groups.
The data in group one were analyzed in terms of observer sensitivity/ specificity (i.e. detection of a hearing loss) for parents and professionals, respectively, using the criterion: normal hearing I 20 dB HL in the better hearing ear. In addition the measured hearing level in the child was related to the observer (parents/ professionals) having suspicion. Finally the cumulative distribution of parents/ professionals suspecting hearing loss in relation to the measured degree of hearing loss in each child was evaluated. A similar data analysis was performed in the children above 84 months, in whom suspicion (complaints) of a hearing loss had caused referral to the examination, and the results compared to the results obtained in the,younger children.
Results Among the 98 children in the age group 49-84 months suspicion of a hearing loss was present in 74% (n = 73). In 63% (n = 46) of the children the parents had raised the suspicion; in 22% (n = 16) it was raised by professionals. No information was available in 11 children. In 37% (n = 27) of the children suspected to have a hearing deficit a BEHL OS-4 kHz > 20 dB was found, indicating a ‘true positive’ observation (i.e. with this level of fence). In terms of correct detection of hearing loss, based on parental/professional observation, 41% (n = 19) of the parents were correct, while 25% (n = 4) of the professionals were correct. The number of false positive observations (BEHL OS-4 kHz I 20 dB HL) was 59% (n = 27) and 75% (n = 12), respectively. The frequency of correct/false positive detection of a hearing loss between parents and professionals is not significant (95% confidence
TABLE
I
Matrix on children in whom suspicion was pre.?enr/absent cross-tabulated to the BEHL 0.5- 4 kM found ui examination (AI In B is indicated the matrix for parents’/profesionafs’ suspicion und rhr rorre.spondinl: c,alues for the hearing lecel found at examination. BEHL 0.5-4
kHz
I2OdBHL
120dBHL
Suspicion present
4.)
27
Suspicion absent
20
.?
Suspicion present (parents)
27
19
Suspicion present (professionals)
16
8
(A)
(B)
limits) 131. The specificity concerning parental/ professional observation of signs from a hearing-impaired child is 50 and 69%, respectively, when using BEHL: 0.5-4 kHz > 20 dB for the diagnosis of hearing impairment. In 23% (n = 23) of the children no suspicion of a hearing loss was present. However, among these a hearing loss > 20 dB HL (BEHL: 0.5-4 kHz1 was demonstrated in 3 children, which corresponds to an observer sensitivity of 88% for parents and professionals (Table I). No information was available in 2 children. In Fig. 3 is demonstrated the relationship between the degree of hearing loss and the age at examination (i.e. identification) in the children suspected of a
120
fEH.[O.Mliz] 0
lal -
80 60:
-40
45
50
56
60
66 &
+ PAilEN~S Fig. 3. Degree indicated
of hearing loss in relation
parents’
(+)
75
OPROF
to age at identification
suspicion, professionals’
(0 ), and
overlapping
80
85
90
100
0 BOTH (i.e. time of examination).
the group of children
(0).
95
In addition
is
in whom suspicion was
+
PROF. +
PARENTS
*AbE 84 MINTHS
Fig. 4. Cumulative distribution of the frequency of parental (+) and professional (*) suspicion in relation to degree of hearing loss. In addition is indicated the cumulative frequency of subjective problems in the group of children > 84 months of age (0 ).
hearing deficit. The figure also demonstrates that 48% (n = 55) of the parents had suspicion of a hearing deficit in their child, while suspicion was present in professionals in 34% (n = 391. Thus an overlap of suspicion was found in 18% (n = 211, which may reflect an exchange of information concerning the child and its behavior between parents and professionals - in this context, predominantly staff at day care institutions. In Fig. 4 is demonstrated the cumulative frequency of parental and professional suspicion (i.e. detection), related to different degrees of the BEHL 0.5-4 kHz. Thus at a hearing level of 20 dB HL 60% of parents notice signs of a hearing deficit in their child, while at the same level 77% among professionals have suspicion. If a criterion of 15 dB HL is used, suspicion will be present in 38% parents and 58% professionals. In the group of children (n = 74) > 84 months of age anticipated to complain of a hearing problem (i.e. hearing disability), a hearing deficit was experienced in 82% (n = 611, causing the referral, while no hearing problem was indicated in 18%
TABLE II Number of children > 7 years of age with/without hearing leoel found at examination BEHL 0.5-4
complaints of hearing problems cross-tabulated to the
kHz
s2QdBHL
>2OdBHL
Complaints
39
22
No complaints
13
0
7
(n = 13). When using a criterion of BEHL OS-4 kHz > 20 dB only 30% (n = 22) in this group of children had confirmed hearing impairment, which is significantly lower (P < 0.05) than the 82% indicating a problem (Table II). The data analyzed in the 61 children are supposed to represent the ‘true value’ indicating the frequency of subjective hearing problems (i.e. disability) at different degrees of hearing level. The cumulative frequency of a hearing problem in relation to degree of hearing level in these children is indicated in Fig. 4. Thus a BEHL 0.5-4 kHz of 14 dB will exhibit a hearing problem in 50% of the children. No differences in hearing level at the 50% frequency of parental suspicion (19 dB), professional suspicion (14 dB), and a subjective hearing problem f 14 dB) were found (P > 0.05). In addition it should be mentioned that the minor differences in frequency between the 3 cumulative distributions in Fig. 4 are not significant at any hearing level.
Discussion The results of the present examination demonstrate that the frequency of correct and false positive suspicion (detection) of a hearing impairment (defined as BEHL 0.5--4 kHz > 20 dB) is similar in parents and professionals; that an observer sensitivity of 88% is present; that the frequency of suspicion (i.e. detection) in parents and professionals in relation to degree of hearing loss corresponds to the frequency of hearing problems, experienced in a reference group of older children with a similar distribution of hearing level. The present data concerning the parental observer specificity and sensitivity support previous investigations, indicating that parents observe the behavioral patterns of their child, and suspect hearing loss if deviations are present - both in sensorineural and conductive hearing disorders [2,7,10]. It has also been demonstrated that the parents are the first to raise suspicion of their child’s hearing loss. In this group of children no differences are found in observer specificity and sensitivity between parents and professionals, nor in degree of hearing level. This is in contrast to a previous investigation of children I 4 years of age, in which it was demonstrated that the parents significantly more frequently are correct in suspecting hearing loss than professionals [16]. This may be ascribed to the more extensive time parents spend together with infants and small children. The high frequency of 82% of experienced hearing problems in the age group above 84 months corresponds to the 74%, in whom suspicion of a hearing loss was present in the age group between 49 and 84 months of age. This further supports that hearing deficits in the BEHL 0.5-4 kHz < 20 dB may cause behavioral problems, at least in conductive disorders. This may have implications for nearly all aspects within pedoaudiology. A significant difference is present in the reference group between the frequency of experienced hearing deficit (82%) and the frequency of hearing impairment. based on the IAPA-definition: BEHL 0.5-4 kHz > 20 dB. Thus the BEHL 0.5-4 kHz defining hearing impairment may be considered inappropriate. However, the
8
majority of children suffered from a conductive hearing disorder due to predominantly otitis media with effusion, while only 7 suffered from a sensorineural hearing disorder. Moreover the fence of hearing impairment/disability may differ in conductive and sensorineural hearing disorders, however the number of children (n = 7) with sensorineural hearing disorders allows no further evaluation on this problem. The WHO criterion for hearing impairment (excluding 4 kHz) has a poor relation to the self-assessed hearing ability in children, which is further supported by the BEHL OS-4 kHz of 14 dB, corresponding to a frequency of 50%, indicating a hearing deficit. In this context it should be taken into account that the audiometry in the children comprising this material was performed in a sound-proof room, according to international standards [9]. Although the present data were obtained from a consecutive series of children, it may be argued that the number in the different subgroups is too iimited to evaluate an objective criterion for hearing impairment/disability. In the clinic major differences between individuals concerning subjective hearing problems, even at the same degree of hearing loss, are known to be present [12]. Thus it seems important that further investigations are performed in order to evaluate the relationship between subjective and objective criteria for hearing impairment and disability - also in children.
Acknowledgement
We are grateful to Professor Peter Alberti, M.D., Department of Oto-Laryngology, Mount Sinai Hospital, Toronto, for his valuable comments and revision of a previous draft of this manuscript.
References 1 Aniansson, G., Methods for assessing high-frequency hearing loss in everyday listening situations, Acta Otorhinolaryngol., Suppl. 320 (1974) 7-50. 2 Chalmers, D., Stewart, E., Silva, P. and Molveina, A., Otitis media with effusion in children. The Dunedin Study. Clinics in Developmental Medicine, Mac Keith Press, Oxford, 1989, p. 108. 3 Ciba Scientific Tables, 7th edn., K. Diem and C. Lentner (Eds.), Geigy, Basel, 1970. 4 Davidson, J., Hyde, M.L. and Alberti, P.W., Epidemiology of hearing impairment in childhood, Stand. Audiol., 30 (1988) 13-20. 5 Davis, A., The prevalence of hearing impairment and reported hearing disability among adults in Great Britain, Int. J. Epidemiol., 18 (1989) 901-907. 6 Haggard, M., Gatehouse, S. and Davis, A., The high prevalence of hearing disorders and its implications for services in the U.K., Br. J. Audio]., 15 (1981) 241-245. 7 Hovind, H. and Parving, A., Detection of hearing impairment in early childhood, Stand. Audiol., 16 (1987) 187-193. 8 Humes, L.E., Understanding the speech-understanding problems of the hearing impaired, J. Am. Acad. Audiol., 2 (1991) 59-69. 9 IS0 389. Acoustics - Standard reference zero for the calibration of pure-tone air-conduction audiometers, International Organization for Standardization, Geneva, 1975.
10 Kankkunen. A., Pre-school children with impaired hearing. Acta Otorhinolaryngol.. Suppl. 391 (1982) I-124. 11 Ostri, B. and ParJing, A.. Longitudinal study of hearing in male subjects an &year follow-up. Br. ,I. Audiol.. 25 (IYYl) 41-48. 12 Parving. A. and Ostri, B., On objective criteria for hearing impairment and hearing disability. Sand. Audiol., 12 (1983) 165-169. 13 Parving, A., Early detection and identification of congenital/early acquired hearing disability. Who takes the initiative? Int. J. Ped. Otorhinolaryngol., 7 (1984) 107-l 17. 14 Parving. A.. Hearing disorders in childhood; some procedures for detection, identification and diagnostic evaluation, Int. J. Ped. Otorhinolatyngol., 9 (lY85) 31-57. IS Parving, A.. Ostri, B.. Katholm, M. and Parbo. J.. On prediction of hearing disability, Audiology. 75 (1986) 12’)-135. I6 Parving, A. and Christensen, B., Children I 4 years of age referred to an audiological department. Int. J. Pet]. Otorhinolaryngol., in press. 17 Pavlovic, C.V., Speech spectrum considerations and speech intelligibility predictions in hearing aid evaluations, J. Speech Hear. Disord., 54 (19X9) 3-8. 1X Skinner. M. and Miller, J.. Amplification bandwidth - an intelligibiiity of speech in quiet and in noise for listeners with sensorineural hearing loss, Audiology. 22 (1983) 253-271. 19 World Health Organization (WHO): International Classification of Impairments. Dlsabilitics. and Iiandicap\, Geneva, 1980.
PEDOT
00784
On criteria for hearing impairment in children Agnete
Parving and Birger Christensen
Department of Audiology, Bispehjerg Hospital, Copenhagen (Dettmark) (Received 4 June 1901) (Accepted 6 August 1991)
rCty words: Hearing-impaired/disabled
child; Criterion:
Parent/professional
Abstract As objective criteria concerning hearing impairment/ disability may be poorly related to the behavioral patterns of children with hearing deficits, the present investigation was performed. A consecutive series of 172 children, who were examined for the first time at the Audiological Department, was subdivided according to age into two groups: one comprising 98 children at an age from 49 to 84 months, the other comprising 74 children > 84 months of age. This second group is supposed to complain of hearing problems if present, and thus constitutes a reference group. Using the criterion for hearing impairment: BEHL 0.5-4 kHz > 20 dB HL, the data demonstrated that the frequency of correct and false positive suspicion (detection) of a hearing impairment is similar in parents and professionals with an observer sensitivity of 88%. In addition the frequency of suspicion in parents and professionals in relation to degree of hearing loss corresponds to the frequency of hearing problems, as experienced in the reference group of older children. A certain discrepancy exists between the applied criterion of BEHL 0.5-4 kHz > 20 dB and the hearing level resulting in deviating behavioral pattern or experienced hearing deficit in children. This may be ascribed to the predominantly conductive hearing loss in the examined sample. It is concluded that additional investigations on criteria for hearing impairment/ disability, including also children with sensorineural hearing loss should be undertaken.
Introduction
According to the World Health Organization (WHO) hearing impairment is defined as any loss or abnormality of psychological, physiological or anatomical Correspondenw NV. Denmark.
to: A. Parving,
Department
of Audiology,
Bispehjerg
Hospital,
DK 2400 Copenhagen
2
structure or function of hearing [19]. To make this definition operational a graded terminology has been included referring to degree of hearing loss (in dB hearing level) in the better hearing ear based on the average of speech frequencies (500, 1000, 2000 Hz). Thus hearing impairment is defined operationally as a hearing loss > 25 dB [19]. However, the importance of the frequency range above 2 kHz for the hearing ability has been emphasized, based on the results of laboratory as well as clinical investigations (see e.g. Refs. 1, 8, 15, 17 and 18). Consequently 4 kHz has been included into the ‘frequency criterion’ and used predominantly in epidemiological investigations [5,6,11]. However, it has been demonstrated in adults that the average of pure tone auditory thresholds at 0.5, 1, 2: 3, 4 kHz r 20 dB HL used as an objective criterion for hearing impairment and hearing disability appeared to be more relevant, when related to subjective hearing problems [12]. The diagnosis of hearing impairment assessed at a more or Iess arbitrary level of fence > 25 dB can be questioned, especially within pedoaudiology, where behavioral signs of hearing deficits are dominating in younger children (i.e. < 7 years of age). However, the advantages of worldwide agreement to uniform criteria and examination procedures for hearing impairment and disability are obvious, as pointed out by Davidson et al. [4]. Consequently a ‘criteria group’ was formed by the International Association of Physicians in Audiology (IAPA 1987) with the task to propose operational criteria for hearing impairment/ disability in children. Based on current knowledge the following operational criterion was recommended: a hearing impairment is present, if the better ear hearing threshold level averaged over the frequencies 0.5, 1, 2, and 4 kHz exceeds 20 dB HL (> 20 dB HL). In other words the hearing is considered to be ‘normal’, if the better hearing ear has an average 5 20 dB hearing threshold level. This change in averaged frequencies and in fence may have implications for future epidemiological investigations, but also for pass/fail criterion within hearing screening in childhood, and thus for the pedoaudiological services offered within the health sectors. However, an objective criterion based on an operational philosophy may be poorly related to the behavioral patterns found in children with hearing deficits [7], and may also differ between observers. Numerous investigations have demonstrated that the parents/family are the first to raise suspicion of a hearing loss in their child, both in sensorineural and conductive hearing disorders [2,10,13]. This investigation was performed in order to further examine the criterion of hearing impairment as it related to both non-professionals (parents/family) and professionals working with children.
Material
A total sample of 172 children (98 males, 74 females, at a median age of 79 months, range 49-205) were included into the investigation, according to the following criteria: their age should be 2 49 months, as the majority of children at this age are capable of performing play audiometry [14], and in addition the
Jot
20
0
49-54
55-60
61-66
67-12
73-78
79-84
1
nonths Fig.
I. Age
distribution
in the total
sample
of children.
years) are collected
All
the children
above
X4 months
of age (7
in one column.
examination should constitute their first audiological evaluation. The children were drawn from a consecutive series of 634 children, referred to and examined at the department during 1.5.89-1.5.90 for various reasons, predominantly problems related to hearing and speech disorders [16]. The age distribution at this first examination in these 172 children is shown in Fig. 1. Procedures
Information on all relevant aspects concerning diagnostic pedoaudiology was registered [16]. For the purpose of the present evaluation the following parameters were evaluated: suspicion/no suspicion present of a hearing deficit; who raised the suspicion: parents/family in contrast to professionals, i.e. general practitioners. ENT doctors, health visitors, pediatricians, staff at institutions (i.e. nursery or kindergarten), psychologists or speech therapists (special teachers); degree of hearing loss for the average of frequencies OS-4 kHz in the better hearing ear (BEHL OS-4 kHz). The suspicion of a hearing loss in younger children is raised by behavioral signs, observed by the parents or professionals or by complaints of a hearing problem in older children ( > 7 years). Thus the material was subdivided into two groups: one comprising 98 children (62 boys, 36 girls, between the age of 49 and 84 months), in whom behavioral signs had caused suspicion of a hearing loss; the second comprising 74 children (36 boys, 38 girls above the age of 84 months), acting as a control group, as the children at this age are anticipated to complain, if ear- or hearing problems are present. A comparison between the BEHL OS-4 kHz in the two groups of children below and above 84 months of age assured that no significant difference was present (Fig. 2).
Fig. 2. Degree of hearing loss in the group of children 5 84 months of age (open columns), and the children > 84 months’of age (hatched columns). Statistical analysis revealed no significant differences in the degree of hearing loss in these two groups.
The data in group one were analyzed in terms of observer sensitivity/ specificity (i.e. detection of a hearing loss) for parents and professionals, respectively, using the criterion: normal hearing I 20 dB HL in the better hearing ear. In addition the measured hearing level in the child was related to the observer (parents/ professionals) having suspicion. Finally the cumulative distribution of parents/ professionals suspecting hearing loss in relation to the measured degree of hearing loss in each child was evaluated. A similar data analysis was performed in the children above 84 months, in whom suspicion (complaints) of a hearing loss had caused referral to the examination, and the results compared to the results obtained in the,younger children.
Results Among the 98 children in the age group 49-84 months suspicion of a hearing loss was present in 74% (n = 73). In 63% (n = 46) of the children the parents had raised the suspicion; in 22% (n = 16) it was raised by professionals. No information was available in 11 children. In 37% (n = 27) of the children suspected to have a hearing deficit a BEHL OS-4 kHz > 20 dB was found, indicating a ‘true positive’ observation (i.e. with this level of fence). In terms of correct detection of hearing loss, based on parental/professional observation, 41% (n = 19) of the parents were correct, while 25% (n = 4) of the professionals were correct. The number of false positive observations (BEHL OS-4 kHz I 20 dB HL) was 59% (n = 27) and 75% (n = 12), respectively. The frequency of correct/false positive detection of a hearing loss between parents and professionals is not significant (95% confidence
TABLE
I
Matrix on children in whom suspicion was pre.?enr/absent cross-tabulated to the BEHL 0.5- 4 kM found ui examination (AI In B is indicated the matrix for parents’/profesionafs’ suspicion und rhr rorre.spondinl: c,alues for the hearing lecel found at examination. BEHL 0.5-4
kHz
I2OdBHL
120dBHL
Suspicion present
4.)
27
Suspicion absent
20
.?
Suspicion present (parents)
27
19
Suspicion present (professionals)
16
8
(A)
(B)
limits) 131. The specificity concerning parental/ professional observation of signs from a hearing-impaired child is 50 and 69%, respectively, when using BEHL: 0.5-4 kHz > 20 dB for the diagnosis of hearing impairment. In 23% (n = 23) of the children no suspicion of a hearing loss was present. However, among these a hearing loss > 20 dB HL (BEHL: 0.5-4 kHz1 was demonstrated in 3 children, which corresponds to an observer sensitivity of 88% for parents and professionals (Table I). No information was available in 2 children. In Fig. 3 is demonstrated the relationship between the degree of hearing loss and the age at examination (i.e. identification) in the children suspected of a
120
fEH.[O.Mliz] 0
lal -
80 60:
-40
45
50
56
60
66 &
+ PAilEN~S Fig. 3. Degree indicated
of hearing loss in relation
parents’
(+)
75
OPROF
to age at identification
suspicion, professionals’
(0 ), and
overlapping
80
85
90
100
0 BOTH (i.e. time of examination).
the group of children
(0).
95
In addition
is
in whom suspicion was
+
PROF. +
PARENTS
*AbE 84 MINTHS
Fig. 4. Cumulative distribution of the frequency of parental (+) and professional (*) suspicion in relation to degree of hearing loss. In addition is indicated the cumulative frequency of subjective problems in the group of children > 84 months of age (0 ).
hearing deficit. The figure also demonstrates that 48% (n = 55) of the parents had suspicion of a hearing deficit in their child, while suspicion was present in professionals in 34% (n = 391. Thus an overlap of suspicion was found in 18% (n = 211, which may reflect an exchange of information concerning the child and its behavior between parents and professionals - in this context, predominantly staff at day care institutions. In Fig. 4 is demonstrated the cumulative frequency of parental and professional suspicion (i.e. detection), related to different degrees of the BEHL 0.5-4 kHz. Thus at a hearing level of 20 dB HL 60% of parents notice signs of a hearing deficit in their child, while at the same level 77% among professionals have suspicion. If a criterion of 15 dB HL is used, suspicion will be present in 38% parents and 58% professionals. In the group of children (n = 74) > 84 months of age anticipated to complain of a hearing problem (i.e. hearing disability), a hearing deficit was experienced in 82% (n = 611, causing the referral, while no hearing problem was indicated in 18%
TABLE II Number of children > 7 years of age with/without hearing leoel found at examination BEHL 0.5-4
complaints of hearing problems cross-tabulated to the
kHz
s2QdBHL
>2OdBHL
Complaints
39
22
No complaints
13
0
7
(n = 13). When using a criterion of BEHL OS-4 kHz > 20 dB only 30% (n = 22) in this group of children had confirmed hearing impairment, which is significantly lower (P < 0.05) than the 82% indicating a problem (Table II). The data analyzed in the 61 children are supposed to represent the ‘true value’ indicating the frequency of subjective hearing problems (i.e. disability) at different degrees of hearing level. The cumulative frequency of a hearing problem in relation to degree of hearing level in these children is indicated in Fig. 4. Thus a BEHL 0.5-4 kHz of 14 dB will exhibit a hearing problem in 50% of the children. No differences in hearing level at the 50% frequency of parental suspicion (19 dB), professional suspicion (14 dB), and a subjective hearing problem f 14 dB) were found (P > 0.05). In addition it should be mentioned that the minor differences in frequency between the 3 cumulative distributions in Fig. 4 are not significant at any hearing level.
Discussion The results of the present examination demonstrate that the frequency of correct and false positive suspicion (detection) of a hearing impairment (defined as BEHL 0.5--4 kHz > 20 dB) is similar in parents and professionals; that an observer sensitivity of 88% is present; that the frequency of suspicion (i.e. detection) in parents and professionals in relation to degree of hearing loss corresponds to the frequency of hearing problems, experienced in a reference group of older children with a similar distribution of hearing level. The present data concerning the parental observer specificity and sensitivity support previous investigations, indicating that parents observe the behavioral patterns of their child, and suspect hearing loss if deviations are present - both in sensorineural and conductive hearing disorders [2,7,10]. It has also been demonstrated that the parents are the first to raise suspicion of their child’s hearing loss. In this group of children no differences are found in observer specificity and sensitivity between parents and professionals, nor in degree of hearing level. This is in contrast to a previous investigation of children I 4 years of age, in which it was demonstrated that the parents significantly more frequently are correct in suspecting hearing loss than professionals [16]. This may be ascribed to the more extensive time parents spend together with infants and small children. The high frequency of 82% of experienced hearing problems in the age group above 84 months corresponds to the 74%, in whom suspicion of a hearing loss was present in the age group between 49 and 84 months of age. This further supports that hearing deficits in the BEHL 0.5-4 kHz < 20 dB may cause behavioral problems, at least in conductive disorders. This may have implications for nearly all aspects within pedoaudiology. A significant difference is present in the reference group between the frequency of experienced hearing deficit (82%) and the frequency of hearing impairment. based on the IAPA-definition: BEHL 0.5-4 kHz > 20 dB. Thus the BEHL 0.5-4 kHz defining hearing impairment may be considered inappropriate. However, the
8
majority of children suffered from a conductive hearing disorder due to predominantly otitis media with effusion, while only 7 suffered from a sensorineural hearing disorder. Moreover the fence of hearing impairment/disability may differ in conductive and sensorineural hearing disorders, however the number of children (n = 7) with sensorineural hearing disorders allows no further evaluation on this problem. The WHO criterion for hearing impairment (excluding 4 kHz) has a poor relation to the self-assessed hearing ability in children, which is further supported by the BEHL OS-4 kHz of 14 dB, corresponding to a frequency of 50%, indicating a hearing deficit. In this context it should be taken into account that the audiometry in the children comprising this material was performed in a sound-proof room, according to international standards [9]. Although the present data were obtained from a consecutive series of children, it may be argued that the number in the different subgroups is too iimited to evaluate an objective criterion for hearing impairment/disability. In the clinic major differences between individuals concerning subjective hearing problems, even at the same degree of hearing loss, are known to be present [12]. Thus it seems important that further investigations are performed in order to evaluate the relationship between subjective and objective criteria for hearing impairment and disability - also in children.
Acknowledgement
We are grateful to Professor Peter Alberti, M.D., Department of Oto-Laryngology, Mount Sinai Hospital, Toronto, for his valuable comments and revision of a previous draft of this manuscript.
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