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CoDAS

On-line version ISSN 2317-1782

CoDAS vol.25 no.3 São Paulo  2013

http://dx.doi.org/10.1590/S2317-17822013000300005 

ORIGINAL ARTICLE

 

Use of the International Classification of Functioning, Disability and Health for monitoring patients using Cochlear Implants

 

Marina MorettinI; Maria Regina Alves CardosoII; Aline Malavasi DelamuraIII; Julia Speranza ZabeuIV; Regina Célia Bortoleto AmantiniIII; Maria Cecília BevilacquaV

IGraduate Program (Doctorate) in Public Health, School of Public Health, Universidade de São Paulo - USP - São Paulo (SP), Brazil
IIEpidemiology Department, School of Public Health, Universidade de São Paulo - USP - São Paulo (SP), Brazil
IIIHospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo - USP - Bauru (SP), Brasil
IVSpeech-Language Pathology and Audiology Course, Bauru School of Dentistry, Universidade de São Paulo - USP - Bauru (SP), Brazil
VSpeech-Language Pathology and Audiology Department, Bauru School of Dentistry, Universidade de São Paulo - USP; Center for Audiological Research, Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo - USP - Bauru (SP), Brazil

Correspondence

 

 


ABSTRACT

PURPOSE: To characterize the profile of patients with cochlear implant as proposed by the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY).
METHODS: This is a descriptive, cross-sectional retrospective study, which examined 30 medical records of patients using the cochlear implant of Centro de Pesquisas Audiológicas; To characterize the profile of the patients, the ICF-CY was used. Regarding the assessment, researchers relied on procedures performed in clinical routine, besides information registered in the medical record. After reviewing the information, it was related to codes from the ICF-CY; with the addition of a qualifier afterwards.
RESULTS: Overall, 55 codes from the ICF were related to the instruments to characterize this population. Regarding the Body Functions field, most participants did not have disabilities related to reception and expression of oral language and auditory functions, with only written language disabilities being found. These same findings were observed in the Activity and Participation Field. Regarding environmental factors, noise and the non-availability of technology resources to assist in the auditory comprehension of noise were characterized as a barrier, as well as the absence of speech therapy.
CONCLUSION: This study concluded that most of the participating children showed no deficiency in the body functions, with difficulties being only reported in relation to school performance. Environmental factors (noise, non-availability of technological resources, absence of speech therapy) were characterized as a barrier. The need to expand assessments in the clinical routine was also noted.

Keywords: Hearing; Hearing loss; Cochlear implant; Child; International Classification of Functioning; Disability and Health


 

 

INTRODUCTION

In the field of intervention in childhood deafness, the cochlear implantation represents the most important advancement in the treatment of children with severe/profound prelingual deafness(1). By providing adequate electrical stimulation to the auditory nerve, the cochlear implant (CI) enables these children to have access to the sounds of which they were previously deprived(2).

In the Brazilian Sistema Único de Saúde (SUS), this resource was added as part of the procedures in 1993, by Ordinance 126. Two more ordinances came later on, establishing the Standards for Registration of Centers for performing cochlear implantation, and Indication and the Criteria for Indication and Contraindication of Cochlear Implants(3,4).

Thus, these ordinances established indication and contraindication criteria of CI for adults and children, the infrastructure a center needs (to be licensed by SUS), the minimum professional staff and equipment required, the amount of monitoring in each case and the realization of rehabilitation. However, as this type of prosthesis is funded by SUS for a limited group of patients, many questions are raised on the results of the use of this device in children, making the selection and indication process of the CI a complex and multidimensional one(5,6).

In clinical practice, there are countless aspects to be investigated in an evaluation. However, it is not always possible to have a multidisciplinary team in charge of services, or to have unified evaluation models that facilitate the detailed understanding of the child's or adult's disability. This may explain why it is possible to observe that evaluations in care services to the population using CI are usually focused on the acoustic benefits, and few describe the effects of the intervention on the functioning of the individual, such as their engagement in social activities, advancement in education, psychological aspects related to the disability and social aspects, such as occupational issues.

Considering this situation, the World Health Organization published, in 2001, the International Classification of Functioning, Disability and Health (ICF)(7), which refers to a new interactive and multidimensional classification system, whose goal is to establish a common and standardized language for the description of functioning and disabilities related to health conditions and health-related states, allowing the comparison of data from these conditions between countries, services, and health care sectors, as well as the monitoring of its evolution in time.

With the ICF, the patient's functionality became the central perspective in health and came to be seen as an asset associated with the health condition, and not merely a consequence of it. All aspects of the patient experience began to be categorized(8). Thus, this classification system consists of four components: Body Functions, Body Structure, Activity and Participation and Environmental Factors(9).

Therefore, the ICF has become a major breakthrough in the classification of functionalities and disabilities, allowing a variety of uses in the health domain, as well as having implications in the use of social security and in the formulation of public policies. It has also being used to meet the needs of research aimed at evaluating the effectiveness of the treatment. It is hoped that it can be applied to a population level in the future, since its use has been restricted to research or specific services for now(10).

It is a valuable tool to evaluate individuals with hearing impairment. The concepts presented in the ICF portray the multidimensional experience reported by individuals with hearing loss. In clinics, its use allows for obtaining an initial profile of the patients, monitoring their progress, evaluating the therapeutic approach proposed and measuring the disability caused by the different levels of each illness or injury. In short, it involves relating diseases to the quality of life of patients(11).

The use of the ICF framework to evaluate results obtained with implanted children over time may help to evaluate other important aspects in the development of a hearing impaired CI user child, besides those related to auditory function and language, and the interactions between these aspects in the treatment planning.

Furthermore, in the case of CI programs in which the care staff proposed by the SUS ordinances consists of different health professionals, such as doctors, speech-language pathologists, psychologists, social workers, among others, the use of a common tool may facilitate the monitoring of the intervention in this population, helping to verify that the outcomes of this rehabilitation program are being achieved. This enables SUS to reorganize and implement their actions, resizing them to accommodate the needs of its audience, further rationalizing the use of resources.

Thus, this study aimed to characterize the profile of CI user patients from the context proposed by the ICF.

 

METHODS

This is a descriptive, cross-sectional retrospective study, developed in the original institution, in partnership with Centro de Pesquisas Audiológicas (CPA) of Hospital de Reabilitação de Anomalias Craniofaciais of Universidade de São Paulo, campus Bauru, the same place where the participating population of individuals with hearing loss and CI users was selected, as well as where the collection of data needed for this study took place.

The study was approved by the Research Ethics Committee of the institution of origin - Research Protocol No. 299/2006, on 10/31/2006. All volunteers received an informative letter and signed an informed consent form regarding their participation in the study and the disclosure of the results, according to Resolution 196/96.

Thirty medical records from CI user patients were surveyed, randomly selected according to the following inclusion criteria: being a CI user; being regularly monitored after surgery in the institution's ambulatory care center (CPA); being between 3 and 18 years of age, of both genders. Medical records relating to patients who did not use the CI for a period greater than 6 months and patients with hypoplasia of the auditory nerve were excluded from the sample.

The sociodemographic and clinical data of the study population were raised to contextualize the research participants.

To characterize the profile of the CI user patients, the Children and Youth version of the International Classification of Functioning, Disability and Health (ICF-CY) was used(12).

In the ICF, the information is organized into two parts, each containing two components: functioning and disability (part 1), divided into body functions and structure, activity and participation; and contextual factors (part 2), consisting of environmental and personal factors.

Each of the classification component/field (Body Structure, Body Function, Activity and Participation and Environmental Factors) can be described in positive or negative terms. In each component/field, there are several classification categories or units, which are expressed by a code to which one or more numerical scales are added, called qualifiers, used to describe the extent or magnitude of the functionality or disability in the category chosen for the study (Chart 1).

In this study, for the assessment of Body Functions, Activities and Participation and Environmental Factors (the field Body Structure was not included), the researchers were based on procedures performed and protocols applied in the study participants' follow-up routine, in addition to information available in the registry of the records of the speech-language pathologist and other professionals responsible for the patient's care in the CPA, such as social workers and psychologists. After review of the information in medical records (data from the last follow-up visit), each piece of information was related to the ICF-CY code that best represented them, with the addition of a qualifier later on, according to each field (Body Functions, Activities/Participation and Environmental Factors), that best suited each individual case.

The procedures applied in the clinical routine that supported this evaluation were the following:

Hearing skills evaluation procedures:

  • Free field audiometry - assesses the audibility threshold. In this examination, patients are positioned at a distance of 1 m from the speaker at 0 azimuth, and asked not to move their head, signaling every time they listen to sound stimuli, even if it is weak.
  • Speech perception test - applied according to the patient's age. Thus, for children aged 6 years and 11 months, the Phonemes and Words Recognition Index was applied(13). For children aged 7 years and above, the Words Recognition Index: Dissyllable List was applied(14). Besides these, the Meaningful Auditory Integration Scale was applied to assess speech perception in children aged 4 years and above with profound hearing loss(15).

The hearing skills were classified according to the Hearing Categories that classify the child's auditory development stage regarding his/her hearing abilities(16). The six Hearing Categories include: 0 - Unable to detect speech; 1 - Speech detection, however, without differentiating stimuli in their supra-segmental aspects; 2 - Perception standard (able to differentiate words by their supra-segmental traces); 3 - Starting words identification (able to differentiate words, in a closed set, based on phonetic information; 4 - Word identification by means of vowel recognition; 5 - Word identification by means of consonant recognition; 6 - Word recognition in an open set.

Language skills evaluation procedures:

  • Meaningful Use of Speech Scale (MUSS)(17). It evaluates the use of oral language by hearing impaired children in their daily lives.
  • Observation of oral communication in playful and directed situations.

Language skills were classified into five language categories that classify the child's language development stage(18). The five language categories include: 1 - This child does not speak and may present undifferentiated vocalization; 2 - This child speaks isolated words; 3 - This child builds two to three element phrases; 4 - This child builds four- or five-word phrases and begins to use connecting elements (pronouns, articles, prepositions); 5 - This child builds phrases with over five words, uses connecting elements, conjugates verbs, uses plurals, etc.

Results analysis methods

The results analysis was performed by the descriptive analysis of the following variables for the description of the study population: gender, age, age at surgery, duration of CI use, hearing category, language category, literacy, education of the mother or guardian, etiology, therapy and socioeconomic status. The results in each field of the ICF-CY (Body Functions, Activities/Participation and Environmental Factors) were reported in percentage, according to the qualifier that is best suited for the population. For the analysis, the data were converted to the statistical software Stata, version 10.0.

 

RESULTS

The 30 study participants underwent CI surgery at the age of 2 years, with the group being at the age of 10 years (minimum of 6 years and maximum of 18 years old) at the time of evaluation and had 8 years of use of the device, on average.

Data on the sociodemographic aspects of the population showed that 93% of the children attended school, and of those, only two were illiterate at the time of evaluation (Table 1).

 

 

Regarding the results focused on etiology, Hearing and Language Categories (Table 2), it was noted that, with respect to the last two aspects, 56.67% of children were in therapy at the time of evaluation, 30% of children have been discharged and 13.33% of children had no access to rehabilitation in their city.

 

 

When the results of the evaluations carried out in the clinical routine were related to the ICF-CY, 55 codes were obtained: 12 for the description of Body Function, 36 codes for Activity and Participation and seven for Environmental Factors. No code from the Structure Body field was included.

After relating the ICF-CY codes, a qualifier was assigned for each child, which represented their performance regarding the selected category.

In the findings regarding the Body Functions field (Table 3), it was observed that the majority of participants had no disability (qualifier 0) in aspects regarding reception and expression of oral language. As for the detection, discrimination, localization, sound lateralization and speech discrimination auditory functions, most patients had no current disability. It is noteworthy that the ability of auditory comprehension was related to code b2308 (auditory functions, other specified). Two participants had severe deficiency in detecting sounds, discriminating and understanding speech. Regarding the function related to written language, patients still had disabilities. There were no specific data on this skill in the medical records for about 20% of the participants, with no possibility, therefore, of evaluating it.

Codes related to the Production and Quality of Voice (b3100, b3101), Joint Functions (b320) and Fluency of Speech (b3300) were not related, because there was no information in the medical records.

For evaluation of the Activity and Participation field, 36 codes were selected, and the results regarding the qualifiers in this field are shown in Table 4.

The children showed difficulties regarding school-related activities. In some cases, it was not possible to characterize aspects of the children's participation (relationships with friends, family, siblings), due to the absence of information on these aspects in their medical records, as well as data on phone use by these patients (use of communication devices) and communication techniques.

Environmental factors were evaluated according to the orientation on ICF-CY to check the influence of these factors on people's performance. They can be qualified as facilitators or barriers to the patient's development. In this study, most of the related codes acted as facilitators in the cases of the 30 participating children, and only the codes related to environmental noise (e250 Sound and e130 Products and technology for education; in this case, using the frequency modulation system - FM) were considered as a barrier to 86% of children (Table 5). In this case, the non-availability of FM in environments such as the classroom can interfere with the performance of the CI user student.

For 13% of children, not undergoing speech therapy was not considered as a barrier or as a facilitator, as these children did not have access to this service with speech-language pathologists (e580 services, systems and health policies, e355 Health professionals).

 

DISCUSSION

This study aimed to characterize the profile of CI user patients from the context proposed by the ICF-CY(12).

It was found that most CI user children who participated in the study showed no deficiency in the Body Functions regarding auditory and language skills, with the only disability reported being regarding the development of reading and writing skills. The same occurred in the Activities and Participation fields, as many children had difficulties in the school performance evaluated by data from medical records. Regarding Environmental factors, noise and non-availability of technological resources to assist in the auditory comprehension of the noise, such as the FM system, were characterized as a barrier for the majority of the population.

Thus, the ICF-CY helped expand the vision on the development of the CI user child. The use of this tool, which emphasizes the role of contextual factors in the individual's welfare, can help professionals from the CI service and the therapist in the treatment planning(19) and in the choice of evaluation instruments(20).

As this model recognizes that a complex interaction of contextual factors (environmental and personal) can shape the development of children with hearing loss, we can, through its use, identify which factors influence the outcomes of children and families(21). In the case of this study, it was found that noise, which is considered an environmental factor, served as a barrier for most children, interfering with their performance in these situations.

Another relevant factor that was characterized was the difficulty of access to therapy. In Brazil, there are few programs that support the (re)habilitation of hearing impaired children, and the detection of sound alone through the CI does not guarantee the development of oral language, because it does not ensure the interpretation of speech sounds. The child needs to be enabled to make use of the perceived sounds and assign them meaning(22). For this reason, society shall not be exempted from its responsibilities as a provider of effective intervention programs, organized and founded, with the support from competent professionals that specialize in the development of oral language with an emphasis on auditory function(23).

Some difficulties were encountered while using the ICF-CY to assess these patients, because, to qualify each of the evaluated aspects, there was a need to base on the results of the procedures performed in the last follow-up visit and the records made by health professionals, and the necessary information was often not available, making it difficult to trace the patients' profile, particularly regarding social aspects. Furthermore, many codes that are essential to the understanding of the whole life perspective of this population, such as aspects related to voice, interactions with people other than family members, use of telephone and communication techniques, such as lip reading, school progression and even data on occupation for older children, were not listed.

In this sense, the evaluation of other aspects of the life of CI users, besides auditory and language skills, can lead to more personalized interventions for this population, thus providing the achievement of better results in all areas of the implant user's life(10).

The deficiency related to written language and performance regarding school activities among patients draws attention in this study. Although the CI allows greater access to information and more benefits related to speech perception and oral language in individuals with severe and profound hearing loss, this result shows that greater attention should be given to the development of reading and writing skills, allowing these patients to achieve similar levels of development to that of their peer listeners. Another issue is the need for better education (training and capacity building) of human resources within the school to receive such children and thus promote their learning(24).

Regarding environmental factors, we observed that most patients had no difficulty in relating to parents and siblings. The environment in which the child lives and the stimulation it receives, especially from their family, are essential for the fostering of their development and play an important role in language acquisition. Therefore, there is a great concern among professionals about how to support parents and guide them as to the conduct regarding the child who received the CI(25).

While social relations are crucial to the children's development, many children with hearing loss and CIs have difficulties initiating and sustaining relationships with colleagues who have normal hearing(26). For children who go to regular schools, poor speech intelligibility can increase the feeling of loneliness(27), and this can lead to difficulties in social integration, becoming a serious concern for parents, educators and mental health professionals. As few studies to date document the area of social welfare on children's CIs and suggest ways of dealing with these difficulties(28), it is necessary that the speech-language pathologist consider this aspect in the CI user child's rehabilitation, identifying risk behaviors and referring them to specialists when needed.

 

CONCLUSION

This study showed that the majority of the participating CI user children showed no deficiency in Body Functions related to auditory and language skills, with deficiencies being only reported in relation to the development of reading and writing skills. The participating children showed difficulties in school performance evaluated from the data on their medical records, and regarding environmental factors, noise and non-availability of technological resources to assist in the auditory comprehension of noise, such as the FM system, were characterized as a barrier to the majority of the population, as well as the absence of speech therapy.

These results suggest that evaluations in the clinical routine must be expanded regarding the following aspects of CI user patients: reading and writing skills, voice, participation in social activities and verification of environmental factors, such as immediate family, extended family, friends, health professionals and the attitude of people around them.

 

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28. Percy-Smith L, Jensen JH, Cayé-Thomasen P, Thomsen J, Gudman M, Lopez AG. Factors that affect the social well-being of children with cochlear implants. Cochlear Implants Int. 2008;9(4):199-214.         [ Links ]

 

 

Correspondence:
Marina Morettin
Centro de Pesquisas Audiológicas, Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo
R. Silvio Marchioni, 3-20
Bauru (SP), Brasil, CEP: 17012-900.
E-mail: mmorettin@usp.br

Received on: 08/08/2012
Accepted on: 03/27/2013
Conflict of interest: nothing to declare.

 

 

Study carried out at the Epidemiology Department, School of Public Health, Universidade de São Paulo - USP - São Paulo (SP), Brazil; Center for Audiological Research, Hospital de Reabilitação de Anomalias Craniofaciais, Universidade de São Paulo - USP - Bauru (SP), Brazil
* MM was responsible for the preparation of the study, data collection and tabulation, and the drafting of the manuscript; MRAC assisted in the preparation and outlining of the study and with the general guidance of the implementation stages, supervision of the data collection and drafting of the manuscript; AMD and JSZ assisted in data collection and tabulation, as well as the drafting of the manuscript; RCBA and MCB assisted in the preparation and outlining the study and in the general guidance of the implementation stages, supervision of the data collection and in drafting the manuscript.

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