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The development of the Geriatric Index of Communicative Ability (GICA) for measuring communicative competence of elderly: A pilot study
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ScienceDirect Speech Communication 56 (2014) 63–69 www.elsevier.com/locate/specom
The development of the Geriatric Index of Communicative Ability (GICA) for measuring communicative competence of elderly: A pilot study JungWan Kim a, ChungMo Nam b, YongWook Kim c, HyangHee Kim c,d,⇑ a Department of Speech and Language Pathology, Daegu University, Gyeongsan 712-714, Republic of Korea Department of Preventive Medicine, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea c Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea d Graduate Program in Speech and Language Pathology, Yonsei University, Seoul 120-752, Republic of Korea b
Received 9 April 2013; received in revised form 25 July 2013; accepted 3 August 2013 Available online 9 August 2013
Abstract A change in communicative ability, among various changes arising during the aging process, may cause various difficulties for the elderly. This study aims to develop a Geriatric Index of Communicative Ability (GICA) and verify its reliability and validity. After organizing the areas required for GICA and defining the categories for the sub-domains, relevant questions were arranged. The final version of GICA was completed through the stages of content and face validity, expert review, and pilot study. The overall reliability of GICA was good and the internal consistency (Cronbach’s a = .786) and test-retest reliability (range of Pearson’s correlation coefficients: .58– .98) were high. Based on this verification of the instrument’s reliability and validity, the completed GICA was organized with three questions in each of six sub-domains: hearing, language comprehension & production, attention & memory, communication efficiency, voice and reading/writing/calculation. As a tool to measure the communicative ability of elderly people reliably and appropriately, GICA is very useful in the early identification of those with communication difficulties among the elderly. Ó 2013 Published by Elsevier B.V. Keywords: Communicative ability; Elderly; Language; Cognition; Index
1. Introduction The number of elderly is increasing rapidly worldwide and aging in Korea is progressing very rapidly (Statistics Korea, 2010). The various problems accompanying this rapid increase in the elderly population require development of numerous services including medical insurance and welfare programs. In old age, all kinds of physical
⇑ Corresponding author. Address: Graduate Program in Speech and Language Pathology & Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul, 50 Yonsei-ro, Sinchon-dong, Seodaemun-gu, Seoul 120-752, Republic of Korea. Tel.: +82 2 2228 3900; fax: +82 2 2227 7984. E-mail address: [email protected] (H. Kim).
0167-6393/$ - see front matter Ó 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.specom.2013.08.001
and social activity tend to decline, and the elderly have unique demographic characteristics which differ from those of younger age groups (The Korean Gerontological Society, 2002). The mental health of the elderly has recently attracted both media and research attention. Since the mental health of the elderly is closely related to successful communication, their quality of life can be improved by examining changes in communicative ability that occur during the aging process and by using the early identification of any problems to ensure the provision of prompt therapeutic information. The important aspects of speech communication include respiration, phonation, articulation, language, and hearing function (Mayerson, 1976). These functions tend to degrade in old age, although there is wide individual vari-
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ation. In other words, the aging of the respiratory system relates to the aging of the other bodily systems, so that the smooth flow and rhythm of speech can be degraded with increasing age due to diminished physiologic skills (Burzynski, 1987). The cartilage and muscles involved in phonation also undergo structural changes in the elderly, which leads to changes in vocal intensity, voice quality, and pitch. These changes combine to give old people a less resonating and more breathy voice (Burzynski, 1987; Mueller et al., 1984; Watson, 1998). The articulatory function requires intricate interactions between the speech mechanisms of the tongue, lips, jaws, and palate. A structural change in the speech mechanism resulting from aging can thus cause articulatory deviations (Mayerson, 1976). Language is affected by such skills as perceptual skills, sensori-motor abilities, intelligence and education. Therefore, the decline in the elderly’s memory, span of attention, problem solving ability and perceptual skills makes it difficult for them to understand sounds and words, and the syntactic complexity of a message also influences the abilities of old people to understand language (Frisina and Frisina, 1997; Gordon-Salant and Fitzgibbons, 1995; Pichora-Fuller et al., 1995; Wingfield et al., 2006; Yonan and Sommers, 2000). Riegel (1973) held that in the aging process, language was stable, and cognitive decrements were reflected in language outputs. In addition, the elderly’s hearing function often degrades. Hearing impairment is so common among the elderly that hearing loss has been reported in 33% (Glorig and Roberts, 1965). Such hearing disorders further hinder the hearing and understanding capability of many elderly as they fail to catch important words and are incapable of understanding what others say under poor listening conditions such as noisy or crowded places (Tun and Wingfield, 1999; Versfeld and Dreschler, 2002; Wingfield and Grossman, 2006). Despite the wide individual variation, difficulties in communicative ability in old age may arise through respiration, voice, hearing, language comprehension and language expression. Therefore, it is needed to develop an index to measure changes in the communicative ability of the elderly by identifying and specifying weaknesses according to various sub-domains. This index can then be used to identify the areas in which speech and language pathologists can help the elderly to maintain effective communication at each stage of old age. 2. Methods 2.1. Instrument development Factors of communicative disorders can be grouped into voice, articulation, language, stuttering and hearing (Hegde, 2001). In old age, however, calculation, attention, working memory, reading and writing abilities, as well as these speech and language abilities, may influence effective communication. Therefore, this study reorganized the domains essential for measures of communicative ability
in old age after consulting the category classifications used in the existing measures of communicative ability (Frattali et al., 1995; Holland et al., 1999; Lomas et al., 1989) and divided the sub-domains into six categories: ‘voice’, ‘hearing’, ‘auditory comprehension’, ‘verbal expression’, ‘reading/writing/calculation’ and ‘attention/memory’. Then various items were prepared within each sub-domain through literature review (Brod et al., 1999; Kim and Kim, 2009). Consequently, 69 items of the first version of the Geriatric Index of Communicative Ability (GICA) were prepared. 2.2. Pilot study 2.2.1. Exploration of content validity To establish the content validity for the first version of GICA, the 69 items were evaluated by 5 focus groups (2 speech and language pathologists with clinical experience of 5–10 years). The communicative ability in the elderly was evaluated by examining the duplication, representation and appropriateness of the items in each sub-domain with a 5-point scale. The 69 items were used according to their Content Validity Index (CVI) as follows: those with a CVI in the range of 0.50–0.799 were modified, those with a CVI of 0.80 or more were used as they were, and those with a CVI of less than 0.50 were excluded since validity was judged as too low (Fehring, 1987). 2.2.2. Questionnaire construction and expert review By administering the questionnaires at random to 20 normal elderly (10 men and 10 women; mean age: 67.3 years; SD: 1.8; mean education: 7.4 years; SD: 3.2), we examined for the presence of any hindering factors such as ambiguous contents, difficult words, and unnecessarily complicated sentence structures (Gronlund, 1988). Through this process, 31 items were selected for the second version of GICA, with 5, 4, 5, 8, 5 and 4 questions in the hearing, voice, auditory comprehension, verbal expression, reading/writing/calculation and attention/memory subdomains, respectively. As for the second preliminary questions that underwent the verification process of content validity, we composed response categories according to the selection type in which the respondents choose one from an answer sheet with 5point scale. In tests for adults, the reliability and consistency are influenced by the number of response categories (Friedenberg, 1995) so that the reliability tends to increase with increasing number of categories (Thorndike et al., 1991). In case of the elderly, however, numerous response categories, such as a 7-point scale, may cause confusion. Therefore, we used a 5-point scale that is generally used in attitude test in self-reporting form or questionnaires of social survey (Likert, 1932; Park, 2001). This 5-point scale consisted of ‘1: always agree, 2: frequently agree, 3: ordinary, 4: rarely agree, 5: absolutely do not agree’. After examining the rubrics, conceptual clarity and briefness of the questions with 5 focus groups as a
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further part of the reexamination step, two things were revised. First, to prevent respondents from replying with only one answer insincerely, we described 7 questions in affirmative form (i.e., I pronounce correctly when speaking) out of 31 questions in total. Second, while the 5-point scale of the second version of GICA corresponds to frequency-based question, through the evaluation that ‘3 points: ordinary’ does not maintain equal interval with 2 points and 4 points which are lied before and after it, we modified it to ‘3: sometimes agree’. 2.2.3. Examine face validity The face validity was verified by placing a tick next to each question to see if they were properly set for the measurement of aged communicative ability on 100 elderly in total while executing the second version of GICA. When the question ‘Not related or not proper’ was ticked, the reason was also commented.
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investigate hearing disturbance and we examined objective hearing threshold (Model: Qualitone Audiometers WR-C, Starkey Laboratories, Inc.) by implementing simple hearing tests. In addition, were implemented GICA for 60 elderly people who represent 30% within 2 weeks to examine test-retest reliability of GICA. As for the scoring method, summated scale was used for GICA, except 7 items which were changed into affirmative forms, which adds score of response scale (1–5 points) of each question. For 7 items in negative form, we scored them with 1–5 points by calculating them in a way of ‘6-(score of relevant response scale). Through this scoring method, we calculated total scores which ranged from 31 points at the minimum to 155 points at the maximum. At the beginning of the interview, we notified the subjects that questions include affirmative and negative forms. We asked them to listen carefully and answer them. 2.4. Statistical analysis
2.2.4. Sampling We recruited 100 community-dwelling elderly subjects. This study defined ‘elderly people’ with the following criteria; from (1) those whose residence was the Republic of Korea and who spoke Korean as the mother tongue and were 65 years or older, and we excluded (2) elderly people who showed performance by 16% or less in criteria of normal group in Korean-Mini Mental State Examination (K-MMSE, Kang, 2006), and (3) elderly people who turned out to be in depression in Geriatric Depression Scale Short Form-Korea Version (GDSSF-K, KI, 1996), and (4) elderly people who corresponded to 27 conditions out of 29 types of diseases which can be related to decline of cognitive function that Christensen et al. (1991) asserted, except questions 28 and 29. It is thought to be meaningless to develop index of communicative ability by excluding elderly people who corresponded to ‘hearing impairment’ of question 28 and ‘illiteracy’ of question 29 since considerable number of elderly people in Korea come under these conditions. The elderly subjects were selected through interviews and written consent was obtained from each participant. 2.3. Methods of administration Since many of the elderly would have had difficulties in reading the questions and writing their responses by themselves, the survey questionnaire was administered by interview in which the researcher read out the contents and wrote the responses down in an answering sheet. In the case of a respondent struggling to understand the example questions and three or more items of the main questions, the survey was continued but the data excluded from the final analysis. We also conducted K-MMSE (Kang, 2006), GDSSF-K (KI, 1996) and GICA for all elderly subjects. We implemented the Hearing Handicap Inventory for the ElderlyScreening Version (Kim et al., 2001) when interviewing to
Descriptive and analytic statistics were computed with the use of SPSS 17.0 ver (Statistical Product and Service Solution, SPSS Inc., 2010), and p-values of <.05 were considered statistically significant. Test-retest reliability was examined using the Pearson correlation analysis. Internal consistency reliability was examined using Cronbach’s coefficient alpha. Factor analysis (principal axis analysis, orthogonal factor rotation) was performed to explore the constructs of the scale. 3. Results 3.1. Characteristics of the study subjects Of 104 elderly enrolled in the study, 100 individuals (50 men and 50 women) were study subjects after excluding 4 individuals due to missing or incomplete data on GICA. The 8 elderly with hearing impairment showed a mean threshold of 39.85 dB, indicating that their hearing impairments were not severe. In addition, since hearing impairment occurs frequently among the elderly, collection of data excluding those with hearing impairment may be considered meaningless. Therefore, the elderly with hearing impairment were included in the analysis of response data. The average score on the K-MMSE was 27.8 (SD = 1.75). The mean age was 69.42 years (SD = 4.43). The mean years of education was 9.2 (SD = 2.2). The mean GDS score was 2.3, indicating that none of the subjects had depression. 3.2. Reliability The internal consistency value, established by means of Cronbach’s alpha coefficient, was 0.786. In the internal consistency analysis among the total score and each question of GICA, the questions whose coefficient alpha a increased when they were removed were items 4, 6, 23, 29 and 30 (Table 1).
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Table 1 Internal consistency of the GICA. Sub-domain
Item number
Corrected item-total correlation
Cronbach’s alpha if item deleted
V (Having a breathy voice when speaking) H (I cannot hear sounds from TV or radio and feel uncomfortable) VE (I use gestures or body language since I cannot express myself well with words) VE (Interrupting someone who is speaking) RWC (I can read and understand notices and manuals) AM (Bringing up a new story without finishing the previous) AM (I forget what I try to speak while speaking) RWC (I sometimes read signs wrong on the subway or bus and get off at the wrong stop) H (difficult to hear what others say in a noisy place) AC (I do not understand long and complicated speech well) V (I can adjust the loudness of my voice well) VE (Having difficulty recalling the word intended) AC (I do not understand what I watch and listen on TV) RWC (I can write down personal information such as name and phone number) H (I cannot hear well when talking on the phone) V (My voice became rough and raspy than before) RWC (When I read a book or newspaper, I have to read the same content many times to understand it) VE (It is difficult for me to start a conversation) VE (I mispronounce some part of a word) AM (I remember well what I learn or get to know newly) H (Having difficulty understanding what others say in a whisper) VE (I speak in simpler words than before) VE (I say something different from what I intend to say) RWC (My numerical skill was weakened than before) AC (I cannot understand well if people speak fast) V (My voice became heavier or thinner than before) VE (I explain repeatedly even simple things) H (I hear a buzzing in my ears) AC (Having difficulty understanding what others feel, through the looks on their face) AC (I do not distinguish a joke from a truth) AM (I cannot remember things well in recent days)
1 2 3
.615 .517 .549
.736 .736 .738
4 5 6 7 8
.152 .545 .451 .587 .441
.787 .738 .787 .738 .741
9 10 11 12 13 14
.643 .607 .389 .475 .582 .367
.733 .736 .740 .739 .737 .739
15 16 17
.632 .507 .619
.734 .736 .735
18 19 20 21 22 23 24 25 26 27 28 29
.469 .561 .595 .647 .469 .443 .477 .706 .492 .344 .732 .405
.737 .737 .737 .733 .737 .788 .738 .733 .737 .740 .735 .789
30 31
.474 .513
.787 .738
GICA: Geriatric Index of Communicative Ability; V: Voice; H: Hearing; VE: Verbal Expression; AC: Auditory Comprehension; AM: Attention/Memory; RWC: Reading/Writing/Calculation.
To assess the test-retest reliability, 30 elderly were asked to complete GICA a second time 2 weeks later. The testretest reliability results revealed that the range of Pearson’s correlation coefficients was 0.58–0.98. As a result of checking the correlations among the 7 questions that were described as a reversible (positively or negatively) among GICA questions, the remaining 5 questions after excluding items 13 and 19 showed high reliability.
new story without finishing the previous), 21 (Having difficulty understanding what others say in a whisper), and 29 (Having difficulty understanding what others feel, through the looks on their face). The reasons included such responses as ‘My ability will be evaluated negatively.’ and ‘I do not want my measured ability exposed.’ Internal construct validity was examined through factor analysis. According to principal axis component, 6 factors accounted for the total variance in the matrix (Table 2).
3.3. Validity 3.4. Final scale Content and face validity were checked via focus group discussion during the stage of instrument development. As a result of the content validity verification, the CVIs of all the questions, which ranged from 0.51–0.94, indicated that none needed to be removed. As a result of face validity verification, the elderly answered ‘Not related nor proper’ on 5 questions: items 1 (Having a breathy voice when speaking), 4 (Interrupting someone who is speaking), 6 (Bringing up a
Questions were selected in reference to factor analysis, specifically the correlation among the sub-questions belonging to each factor, the tendency of the elderly to respond, and the internal attributes of the applicable questions. For instance, question item 2 showed a strong positive correlation with question items 9 (Difficult to hear what others say in a noisy place) and 21. In other words, the elderly
J. Kim et al. / Speech Communication 56 (2014) 63–69 Table 2 Factor analysis results of the GICA. Item number
Factor
15 2 28 22 25 10 7 20 31 14 24 17 18 3 27 1 26 11
.707 .687 .607
1
2
3
4
5
6
.758 .566 .536
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related to communication method were bound in one sub-domain. Therefore, the former was named ‘language comprehension/expression’, and the latter as ‘communication efficiency’. The 18 questions finally selected were composed of 6 sub-domains with 3 questions each. The distribution and contents of the GICA questions are presented in the Appendix. 3.5. Scoring system of GICA
.661 .564 .553
In the final version of GICA, the test questions were arrayed in the same sequential order as in the second version. The scoring method was such that, like in the pilot test, where scores were assigned from 1 to 5 points based on a 5-point scale, the total score range of this test from 18 to 90 points, with the higher being the better.
.724 .571 .570 .589 .499 .395 .799 .731 .517
GICA: Geriatric Index of Communicative Ability.
that reported good hearing ability in question item 2 responded as having good ability on question items 9 and 21 as well, and thus these 3 questions were regarded as measured repetitively on similar abilities. Question item 9 indicated that the elderly showed a low level in executing ability overall regardless of their hearing impairment condition. In other words, since the elderly with normal hearing ability also suffered a decrease in speech perception in noisy environments, this question was considered to indicate the conditions of attention/memory, sound perceiving ability and language comprehension ability simultaneously. Question item 21 did not reflect a common situation for the elderly, so the hearing impairment experts opined that this question lacked sensitivity as a test question. Therefore, question items 9 and 21 were removed through focus group discussion. In addition, question item 12 (Having difficulty recalling the word intended) is applicable to verbal expression ability at a word level, but with healthy elderly, this question may be related to short-term memory ability rather than to verbal expression purely in itself. As a result of factor analysis, question item 12 was classified in the attention/memory domain. However, the deterioration of naming ability that occurs in the normal aging process is only pertinent to language ability in general rather than affecting memory, attention or perceiving ability. The tools used in clinical linguistic and psychological evaluations classify naming ability in the verbal expression area, so this question was deleted based on the focus group discussion. Thus, through the reliability and validity analysis and the focus group discussion, 18 questions remained in the final version of GICA. In the sub-domain classes that were used in the first and second versions of GICA, ‘auditory comprehension’ and ‘verbal expression’ were bound in one sub-domain, and among the ‘verbal expression’ sub-domains, 3 questions
4. Discussions The proposed GICA, based on instrument development, pilot study and focus group feedback, demonstrated good internal consistency, test-retest reliability, and internal construct validity. GICA is fast in evaluation, taking only 8– 12 min to administer. The tailoring of the items in this index to target specifically the elderly is anticipated to identify the changes in communication ability occurring in the aging process in detail. The proposed GICA is a self-reported, subjective questionnaire for the elderly. The 69 items of the first version of GICA generated at the early stage of instrument development were reduced to 18 items through verification of content validity and face validity, and pilot study and expert review. The variables considered at the time of pilot testing included whether or not the item is a common deficit that is reported frequently among normal elderly and whether or not the item is the same as any of the items already included. As the 18 final-version items were selected through a multi-step procedure, they need to be measured over time to determine any degradation in the elderly’s communicative ability resulting from the normal aging process. The tools to measure communicative ability were generally examined on ability by being divided into linguistic comprehension and expression (Hegde, 2001). However, although such classification may provide useful information in diagnosing aphasic patients that lack executing ability in speaking, hearing, reading or writing, it is not suitable for identifying the communicative ability of the general elderly. As a result of this study, auditory comprehension and verbal expression ability were bound as one factor, and the abilities related to the efficiency of communication such as verbal expression and difficulty of dialog starting were classified as one factor. This indicated that language comprehension and verbal expression ability in ordinary communication situations work simultaneously in a combined manner and that effective communication
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Appendix Communication profile for elderly.
H: Hearing; V: Voice; LCP: Language Comprehension/Production; CE: Communication Efficiency; AM: Attention/Memory; RWC: Reading/Writing/ Calculation. Light shaded item calculated as ‘6-(applicable score)’ (e.g., r ! 6–(1) = 5 rating, s ! 6–(2) = 4 rating).
requires significant consideration for the efficiency of communication. The reliability and validity of GICA were demonstrated in this study. However, the results are limited because the study was conducted mostly in large cities of Korea and therefore did not reflect the trends of rural communities. Therefore, follow-up study must be done to cover the elderly in small medium cities and rural areas, and to investigate the differences of communication ability according to gender, age, years of education and hearing impairment. In addition, the application of GICA to middle-aged individuals will enable identification of the sub-domain that exhibits the first decrease before the elderly period. References Brod, M., Stewart, A.L., Sands, L., et al., 1999. Conceptualization and measurement of quality of life in dementia: the dementia quality of life instrument (DQoL). Gerontologist 39, 25–35. Burzynski, C.M., 1987. The voice. In: Muelle, H.G., Geoffrey, V.C. (Eds.), Communication Disorders in Aging. Gallaudet University Press, Washington, pp. 214–237. Christensen, K.J., Multhaup, K.S., Nordstrom, S., et al., 1991. A cognitive battery for dementia: development and measurement characteristics. Psychological Assessment 3 (2), 168–174. Fehring, R.J., 1987. Methods to validate nursing diagnoses. Heart and Lung 16, 625–629. Frattali, C.M., Thompson, C.K., Holland, A.L., Wohl, C.B., & Ferketic, M.M., 1995. American Speech Language Hearing Association Functional assessment of communication skills for adults (ASHA FACS). Rockville, MD: American Speech-Language-Hearing Association.
Friedenberg, L., 1995. Psychological Testing: Design, Analysis, and Use. Allyn and Bacon, Boston. Frisina, D.R., Frisina, R.D., 1997. Speech recognition in noise and presbycusis: relations to possible neural mechanisms. Hearing Research 106 (1–2), 95–104. Glorig, A., Roberts, J., 1965. Hearing levels of adults by age and sex. (US Public Health Services, Series 11, No, 11). Washinton, DC: Department of Health, Education, and Welfare. Gordon-Salant, S., Fitzgibbons, P.J., 1995. Temporal factors and speech recognition performance in young and elderly listeners. Journal of Speech and Hearing Research 36, 1276–1285. Gronlund, N.E., 1988. How to Construct Achievement Tests. PrenticeHall, Inc., NJ. Hegde, M.N., 2001. Introduction to Communicative Disorders, third ed. Pro-Ed, Austin, TX. Holland, A.L., Frattali, C.M., Fromm, D., 1999. Communication Activities in Daily Living, second ed. Pro-Ed, Austin, TX. Kang, Y.W., 2006. A normative study of the Korean-mini mental state examination (K-MMSE) in the elderly. Korean Journal of Psychology 25, 1–12. Ki, B.S., 1996. A Preliminary study for the standardization of geriatric depression scale short form-Korea version. Journal of the Korean Neuropsychiatric Association 35 (2), 298–307. Kim, J.W., Kim, H., 2009. Communicative ability in normal aging: a review. Korean Journal of Communication Disorders 14, 495–513. Kim, Y.S., Won, C.W., Kim, B.S., et al., 2001. Usability of HHIE-S as a screening test of hearing impairment in the Korean elderly. Journal of the Korean Academy of Family Medicine 22 (6), 878–885. Likert, R., 1932. A technique for the measurement of attitudes. Archives of Psychology 40, 1–55. Lomas, J., Pickard, L., Bester, S., Elbard, H., Finlayson, A., & Zoghaib, C. 1989. The communicative effectiveness index: Development and psychometric evaluation of a functional communication measure for adult aphasia. Journal of speech and hearing disorders 54 (1), pp. 113–124.
J. Kim et al. / Speech Communication 56 (2014) 63–69 Mayerson, M.D., 1976. The effects of aging on communication. Journal of Gerontology 31, 29–38. Mueller, P.B., Sweeney, R.J., Baribeau, L.J., 1984. Acoustic and morphologic study of the senescent voice. Ear, Nose and Throat Journal 63, 292–295. Park, J., 2001. Grade response model. Seoul: educational science. Pichora-Fuller, M.K., Schneider, B.A., Daneman, M., 1995. How young and old adults listen to and remember speech in noise. Journal of the Acoustical Society of America 97 (1), 593–608. Riegel, K.F., 1973. Language and cognition. Some life-span developmental issues. Gerontologist 13, 478–482. Statistics Korea, 2010. Elderly statistics in 2010. Seoul, Statistics Korea. The Korean Gerontological Society, 2002. A review on the gerontological studies. Seoul: Daeyoung. Thorndike, R.M., Cunningham, G.K., Thorndike, R.L., et al., 1991. Measurement and Evaluation in Psychology and Education, fifth ed. Macmillan, Inc., NY. Tun, P.A., Wingfield, A., 1999. One voice too many: adult age differences in language processing with different types of distracting sounds. Journal of Gerontology: Psychological Sciences 54B, 317–327.
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Versfeld, N.J., Dreschler, W.A., 2002. The relationship between the intelligibility of time-compressed speech and speech in noise in young and elderly listeners. The Journal of the Acoustical Society of America 111, 401–408. Watson, B.C., 1998. Fundamental frequency during phonetically governed devoicing in normal young and aged speakers. The Journal of the Acoustical Society of America 103, 3642–3647. Wingfield, A., Grossman, M., 2006. Language and the aging brain: patterns of neural compensation revealed by functional brain imaging. Journal of Neurophysiology 96 (6), 2830–2839. Wingfield, A., McCoy, S.L., Peelle, J.E., et al., 2006. Effects of adult aging and hearing loss on comprehension of rapid speech varying in syntactic complexity. Journal of the American Academy of Audiology 17 (7), 487–497. Yonan, C.A., Sommers, M.S., 2000. The effects of talker familiarity on spoken word identification in younger and older listeners. Psychology and Aging 15 (1), 88–99.
ScienceDirect Speech Communication 56 (2014) 63–69 www.elsevier.com/locate/specom
The development of the Geriatric Index of Communicative Ability (GICA) for measuring communicative competence of elderly: A pilot study JungWan Kim a, ChungMo Nam b, YongWook Kim c, HyangHee Kim c,d,⇑ a Department of Speech and Language Pathology, Daegu University, Gyeongsan 712-714, Republic of Korea Department of Preventive Medicine, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea c Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul 120-752, Republic of Korea d Graduate Program in Speech and Language Pathology, Yonsei University, Seoul 120-752, Republic of Korea b
Received 9 April 2013; received in revised form 25 July 2013; accepted 3 August 2013 Available online 9 August 2013
Abstract A change in communicative ability, among various changes arising during the aging process, may cause various difficulties for the elderly. This study aims to develop a Geriatric Index of Communicative Ability (GICA) and verify its reliability and validity. After organizing the areas required for GICA and defining the categories for the sub-domains, relevant questions were arranged. The final version of GICA was completed through the stages of content and face validity, expert review, and pilot study. The overall reliability of GICA was good and the internal consistency (Cronbach’s a = .786) and test-retest reliability (range of Pearson’s correlation coefficients: .58– .98) were high. Based on this verification of the instrument’s reliability and validity, the completed GICA was organized with three questions in each of six sub-domains: hearing, language comprehension & production, attention & memory, communication efficiency, voice and reading/writing/calculation. As a tool to measure the communicative ability of elderly people reliably and appropriately, GICA is very useful in the early identification of those with communication difficulties among the elderly. Ó 2013 Published by Elsevier B.V. Keywords: Communicative ability; Elderly; Language; Cognition; Index
1. Introduction The number of elderly is increasing rapidly worldwide and aging in Korea is progressing very rapidly (Statistics Korea, 2010). The various problems accompanying this rapid increase in the elderly population require development of numerous services including medical insurance and welfare programs. In old age, all kinds of physical
⇑ Corresponding author. Address: Graduate Program in Speech and Language Pathology & Department and Research Institute of Rehabilitation Medicine, Yonsei University College of Medicine, Seoul, 50 Yonsei-ro, Sinchon-dong, Seodaemun-gu, Seoul 120-752, Republic of Korea. Tel.: +82 2 2228 3900; fax: +82 2 2227 7984. E-mail address: [email protected] (H. Kim).
0167-6393/$ - see front matter Ó 2013 Published by Elsevier B.V. http://dx.doi.org/10.1016/j.specom.2013.08.001
and social activity tend to decline, and the elderly have unique demographic characteristics which differ from those of younger age groups (The Korean Gerontological Society, 2002). The mental health of the elderly has recently attracted both media and research attention. Since the mental health of the elderly is closely related to successful communication, their quality of life can be improved by examining changes in communicative ability that occur during the aging process and by using the early identification of any problems to ensure the provision of prompt therapeutic information. The important aspects of speech communication include respiration, phonation, articulation, language, and hearing function (Mayerson, 1976). These functions tend to degrade in old age, although there is wide individual vari-
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ation. In other words, the aging of the respiratory system relates to the aging of the other bodily systems, so that the smooth flow and rhythm of speech can be degraded with increasing age due to diminished physiologic skills (Burzynski, 1987). The cartilage and muscles involved in phonation also undergo structural changes in the elderly, which leads to changes in vocal intensity, voice quality, and pitch. These changes combine to give old people a less resonating and more breathy voice (Burzynski, 1987; Mueller et al., 1984; Watson, 1998). The articulatory function requires intricate interactions between the speech mechanisms of the tongue, lips, jaws, and palate. A structural change in the speech mechanism resulting from aging can thus cause articulatory deviations (Mayerson, 1976). Language is affected by such skills as perceptual skills, sensori-motor abilities, intelligence and education. Therefore, the decline in the elderly’s memory, span of attention, problem solving ability and perceptual skills makes it difficult for them to understand sounds and words, and the syntactic complexity of a message also influences the abilities of old people to understand language (Frisina and Frisina, 1997; Gordon-Salant and Fitzgibbons, 1995; Pichora-Fuller et al., 1995; Wingfield et al., 2006; Yonan and Sommers, 2000). Riegel (1973) held that in the aging process, language was stable, and cognitive decrements were reflected in language outputs. In addition, the elderly’s hearing function often degrades. Hearing impairment is so common among the elderly that hearing loss has been reported in 33% (Glorig and Roberts, 1965). Such hearing disorders further hinder the hearing and understanding capability of many elderly as they fail to catch important words and are incapable of understanding what others say under poor listening conditions such as noisy or crowded places (Tun and Wingfield, 1999; Versfeld and Dreschler, 2002; Wingfield and Grossman, 2006). Despite the wide individual variation, difficulties in communicative ability in old age may arise through respiration, voice, hearing, language comprehension and language expression. Therefore, it is needed to develop an index to measure changes in the communicative ability of the elderly by identifying and specifying weaknesses according to various sub-domains. This index can then be used to identify the areas in which speech and language pathologists can help the elderly to maintain effective communication at each stage of old age. 2. Methods 2.1. Instrument development Factors of communicative disorders can be grouped into voice, articulation, language, stuttering and hearing (Hegde, 2001). In old age, however, calculation, attention, working memory, reading and writing abilities, as well as these speech and language abilities, may influence effective communication. Therefore, this study reorganized the domains essential for measures of communicative ability
in old age after consulting the category classifications used in the existing measures of communicative ability (Frattali et al., 1995; Holland et al., 1999; Lomas et al., 1989) and divided the sub-domains into six categories: ‘voice’, ‘hearing’, ‘auditory comprehension’, ‘verbal expression’, ‘reading/writing/calculation’ and ‘attention/memory’. Then various items were prepared within each sub-domain through literature review (Brod et al., 1999; Kim and Kim, 2009). Consequently, 69 items of the first version of the Geriatric Index of Communicative Ability (GICA) were prepared. 2.2. Pilot study 2.2.1. Exploration of content validity To establish the content validity for the first version of GICA, the 69 items were evaluated by 5 focus groups (2 speech and language pathologists with clinical experience of 5–10 years). The communicative ability in the elderly was evaluated by examining the duplication, representation and appropriateness of the items in each sub-domain with a 5-point scale. The 69 items were used according to their Content Validity Index (CVI) as follows: those with a CVI in the range of 0.50–0.799 were modified, those with a CVI of 0.80 or more were used as they were, and those with a CVI of less than 0.50 were excluded since validity was judged as too low (Fehring, 1987). 2.2.2. Questionnaire construction and expert review By administering the questionnaires at random to 20 normal elderly (10 men and 10 women; mean age: 67.3 years; SD: 1.8; mean education: 7.4 years; SD: 3.2), we examined for the presence of any hindering factors such as ambiguous contents, difficult words, and unnecessarily complicated sentence structures (Gronlund, 1988). Through this process, 31 items were selected for the second version of GICA, with 5, 4, 5, 8, 5 and 4 questions in the hearing, voice, auditory comprehension, verbal expression, reading/writing/calculation and attention/memory subdomains, respectively. As for the second preliminary questions that underwent the verification process of content validity, we composed response categories according to the selection type in which the respondents choose one from an answer sheet with 5point scale. In tests for adults, the reliability and consistency are influenced by the number of response categories (Friedenberg, 1995) so that the reliability tends to increase with increasing number of categories (Thorndike et al., 1991). In case of the elderly, however, numerous response categories, such as a 7-point scale, may cause confusion. Therefore, we used a 5-point scale that is generally used in attitude test in self-reporting form or questionnaires of social survey (Likert, 1932; Park, 2001). This 5-point scale consisted of ‘1: always agree, 2: frequently agree, 3: ordinary, 4: rarely agree, 5: absolutely do not agree’. After examining the rubrics, conceptual clarity and briefness of the questions with 5 focus groups as a
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further part of the reexamination step, two things were revised. First, to prevent respondents from replying with only one answer insincerely, we described 7 questions in affirmative form (i.e., I pronounce correctly when speaking) out of 31 questions in total. Second, while the 5-point scale of the second version of GICA corresponds to frequency-based question, through the evaluation that ‘3 points: ordinary’ does not maintain equal interval with 2 points and 4 points which are lied before and after it, we modified it to ‘3: sometimes agree’. 2.2.3. Examine face validity The face validity was verified by placing a tick next to each question to see if they were properly set for the measurement of aged communicative ability on 100 elderly in total while executing the second version of GICA. When the question ‘Not related or not proper’ was ticked, the reason was also commented.
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investigate hearing disturbance and we examined objective hearing threshold (Model: Qualitone Audiometers WR-C, Starkey Laboratories, Inc.) by implementing simple hearing tests. In addition, were implemented GICA for 60 elderly people who represent 30% within 2 weeks to examine test-retest reliability of GICA. As for the scoring method, summated scale was used for GICA, except 7 items which were changed into affirmative forms, which adds score of response scale (1–5 points) of each question. For 7 items in negative form, we scored them with 1–5 points by calculating them in a way of ‘6-(score of relevant response scale). Through this scoring method, we calculated total scores which ranged from 31 points at the minimum to 155 points at the maximum. At the beginning of the interview, we notified the subjects that questions include affirmative and negative forms. We asked them to listen carefully and answer them. 2.4. Statistical analysis
2.2.4. Sampling We recruited 100 community-dwelling elderly subjects. This study defined ‘elderly people’ with the following criteria; from (1) those whose residence was the Republic of Korea and who spoke Korean as the mother tongue and were 65 years or older, and we excluded (2) elderly people who showed performance by 16% or less in criteria of normal group in Korean-Mini Mental State Examination (K-MMSE, Kang, 2006), and (3) elderly people who turned out to be in depression in Geriatric Depression Scale Short Form-Korea Version (GDSSF-K, KI, 1996), and (4) elderly people who corresponded to 27 conditions out of 29 types of diseases which can be related to decline of cognitive function that Christensen et al. (1991) asserted, except questions 28 and 29. It is thought to be meaningless to develop index of communicative ability by excluding elderly people who corresponded to ‘hearing impairment’ of question 28 and ‘illiteracy’ of question 29 since considerable number of elderly people in Korea come under these conditions. The elderly subjects were selected through interviews and written consent was obtained from each participant. 2.3. Methods of administration Since many of the elderly would have had difficulties in reading the questions and writing their responses by themselves, the survey questionnaire was administered by interview in which the researcher read out the contents and wrote the responses down in an answering sheet. In the case of a respondent struggling to understand the example questions and three or more items of the main questions, the survey was continued but the data excluded from the final analysis. We also conducted K-MMSE (Kang, 2006), GDSSF-K (KI, 1996) and GICA for all elderly subjects. We implemented the Hearing Handicap Inventory for the ElderlyScreening Version (Kim et al., 2001) when interviewing to
Descriptive and analytic statistics were computed with the use of SPSS 17.0 ver (Statistical Product and Service Solution, SPSS Inc., 2010), and p-values of <.05 were considered statistically significant. Test-retest reliability was examined using the Pearson correlation analysis. Internal consistency reliability was examined using Cronbach’s coefficient alpha. Factor analysis (principal axis analysis, orthogonal factor rotation) was performed to explore the constructs of the scale. 3. Results 3.1. Characteristics of the study subjects Of 104 elderly enrolled in the study, 100 individuals (50 men and 50 women) were study subjects after excluding 4 individuals due to missing or incomplete data on GICA. The 8 elderly with hearing impairment showed a mean threshold of 39.85 dB, indicating that their hearing impairments were not severe. In addition, since hearing impairment occurs frequently among the elderly, collection of data excluding those with hearing impairment may be considered meaningless. Therefore, the elderly with hearing impairment were included in the analysis of response data. The average score on the K-MMSE was 27.8 (SD = 1.75). The mean age was 69.42 years (SD = 4.43). The mean years of education was 9.2 (SD = 2.2). The mean GDS score was 2.3, indicating that none of the subjects had depression. 3.2. Reliability The internal consistency value, established by means of Cronbach’s alpha coefficient, was 0.786. In the internal consistency analysis among the total score and each question of GICA, the questions whose coefficient alpha a increased when they were removed were items 4, 6, 23, 29 and 30 (Table 1).
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Table 1 Internal consistency of the GICA. Sub-domain
Item number
Corrected item-total correlation
Cronbach’s alpha if item deleted
V (Having a breathy voice when speaking) H (I cannot hear sounds from TV or radio and feel uncomfortable) VE (I use gestures or body language since I cannot express myself well with words) VE (Interrupting someone who is speaking) RWC (I can read and understand notices and manuals) AM (Bringing up a new story without finishing the previous) AM (I forget what I try to speak while speaking) RWC (I sometimes read signs wrong on the subway or bus and get off at the wrong stop) H (difficult to hear what others say in a noisy place) AC (I do not understand long and complicated speech well) V (I can adjust the loudness of my voice well) VE (Having difficulty recalling the word intended) AC (I do not understand what I watch and listen on TV) RWC (I can write down personal information such as name and phone number) H (I cannot hear well when talking on the phone) V (My voice became rough and raspy than before) RWC (When I read a book or newspaper, I have to read the same content many times to understand it) VE (It is difficult for me to start a conversation) VE (I mispronounce some part of a word) AM (I remember well what I learn or get to know newly) H (Having difficulty understanding what others say in a whisper) VE (I speak in simpler words than before) VE (I say something different from what I intend to say) RWC (My numerical skill was weakened than before) AC (I cannot understand well if people speak fast) V (My voice became heavier or thinner than before) VE (I explain repeatedly even simple things) H (I hear a buzzing in my ears) AC (Having difficulty understanding what others feel, through the looks on their face) AC (I do not distinguish a joke from a truth) AM (I cannot remember things well in recent days)
1 2 3
.615 .517 .549
.736 .736 .738
4 5 6 7 8
.152 .545 .451 .587 .441
.787 .738 .787 .738 .741
9 10 11 12 13 14
.643 .607 .389 .475 .582 .367
.733 .736 .740 .739 .737 .739
15 16 17
.632 .507 .619
.734 .736 .735
18 19 20 21 22 23 24 25 26 27 28 29
.469 .561 .595 .647 .469 .443 .477 .706 .492 .344 .732 .405
.737 .737 .737 .733 .737 .788 .738 .733 .737 .740 .735 .789
30 31
.474 .513
.787 .738
GICA: Geriatric Index of Communicative Ability; V: Voice; H: Hearing; VE: Verbal Expression; AC: Auditory Comprehension; AM: Attention/Memory; RWC: Reading/Writing/Calculation.
To assess the test-retest reliability, 30 elderly were asked to complete GICA a second time 2 weeks later. The testretest reliability results revealed that the range of Pearson’s correlation coefficients was 0.58–0.98. As a result of checking the correlations among the 7 questions that were described as a reversible (positively or negatively) among GICA questions, the remaining 5 questions after excluding items 13 and 19 showed high reliability.
new story without finishing the previous), 21 (Having difficulty understanding what others say in a whisper), and 29 (Having difficulty understanding what others feel, through the looks on their face). The reasons included such responses as ‘My ability will be evaluated negatively.’ and ‘I do not want my measured ability exposed.’ Internal construct validity was examined through factor analysis. According to principal axis component, 6 factors accounted for the total variance in the matrix (Table 2).
3.3. Validity 3.4. Final scale Content and face validity were checked via focus group discussion during the stage of instrument development. As a result of the content validity verification, the CVIs of all the questions, which ranged from 0.51–0.94, indicated that none needed to be removed. As a result of face validity verification, the elderly answered ‘Not related nor proper’ on 5 questions: items 1 (Having a breathy voice when speaking), 4 (Interrupting someone who is speaking), 6 (Bringing up a
Questions were selected in reference to factor analysis, specifically the correlation among the sub-questions belonging to each factor, the tendency of the elderly to respond, and the internal attributes of the applicable questions. For instance, question item 2 showed a strong positive correlation with question items 9 (Difficult to hear what others say in a noisy place) and 21. In other words, the elderly
J. Kim et al. / Speech Communication 56 (2014) 63–69 Table 2 Factor analysis results of the GICA. Item number
Factor
15 2 28 22 25 10 7 20 31 14 24 17 18 3 27 1 26 11
.707 .687 .607
1
2
3
4
5
6
.758 .566 .536
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related to communication method were bound in one sub-domain. Therefore, the former was named ‘language comprehension/expression’, and the latter as ‘communication efficiency’. The 18 questions finally selected were composed of 6 sub-domains with 3 questions each. The distribution and contents of the GICA questions are presented in the Appendix. 3.5. Scoring system of GICA
.661 .564 .553
In the final version of GICA, the test questions were arrayed in the same sequential order as in the second version. The scoring method was such that, like in the pilot test, where scores were assigned from 1 to 5 points based on a 5-point scale, the total score range of this test from 18 to 90 points, with the higher being the better.
.724 .571 .570 .589 .499 .395 .799 .731 .517
GICA: Geriatric Index of Communicative Ability.
that reported good hearing ability in question item 2 responded as having good ability on question items 9 and 21 as well, and thus these 3 questions were regarded as measured repetitively on similar abilities. Question item 9 indicated that the elderly showed a low level in executing ability overall regardless of their hearing impairment condition. In other words, since the elderly with normal hearing ability also suffered a decrease in speech perception in noisy environments, this question was considered to indicate the conditions of attention/memory, sound perceiving ability and language comprehension ability simultaneously. Question item 21 did not reflect a common situation for the elderly, so the hearing impairment experts opined that this question lacked sensitivity as a test question. Therefore, question items 9 and 21 were removed through focus group discussion. In addition, question item 12 (Having difficulty recalling the word intended) is applicable to verbal expression ability at a word level, but with healthy elderly, this question may be related to short-term memory ability rather than to verbal expression purely in itself. As a result of factor analysis, question item 12 was classified in the attention/memory domain. However, the deterioration of naming ability that occurs in the normal aging process is only pertinent to language ability in general rather than affecting memory, attention or perceiving ability. The tools used in clinical linguistic and psychological evaluations classify naming ability in the verbal expression area, so this question was deleted based on the focus group discussion. Thus, through the reliability and validity analysis and the focus group discussion, 18 questions remained in the final version of GICA. In the sub-domain classes that were used in the first and second versions of GICA, ‘auditory comprehension’ and ‘verbal expression’ were bound in one sub-domain, and among the ‘verbal expression’ sub-domains, 3 questions
4. Discussions The proposed GICA, based on instrument development, pilot study and focus group feedback, demonstrated good internal consistency, test-retest reliability, and internal construct validity. GICA is fast in evaluation, taking only 8– 12 min to administer. The tailoring of the items in this index to target specifically the elderly is anticipated to identify the changes in communication ability occurring in the aging process in detail. The proposed GICA is a self-reported, subjective questionnaire for the elderly. The 69 items of the first version of GICA generated at the early stage of instrument development were reduced to 18 items through verification of content validity and face validity, and pilot study and expert review. The variables considered at the time of pilot testing included whether or not the item is a common deficit that is reported frequently among normal elderly and whether or not the item is the same as any of the items already included. As the 18 final-version items were selected through a multi-step procedure, they need to be measured over time to determine any degradation in the elderly’s communicative ability resulting from the normal aging process. The tools to measure communicative ability were generally examined on ability by being divided into linguistic comprehension and expression (Hegde, 2001). However, although such classification may provide useful information in diagnosing aphasic patients that lack executing ability in speaking, hearing, reading or writing, it is not suitable for identifying the communicative ability of the general elderly. As a result of this study, auditory comprehension and verbal expression ability were bound as one factor, and the abilities related to the efficiency of communication such as verbal expression and difficulty of dialog starting were classified as one factor. This indicated that language comprehension and verbal expression ability in ordinary communication situations work simultaneously in a combined manner and that effective communication
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Appendix Communication profile for elderly.
H: Hearing; V: Voice; LCP: Language Comprehension/Production; CE: Communication Efficiency; AM: Attention/Memory; RWC: Reading/Writing/ Calculation. Light shaded item calculated as ‘6-(applicable score)’ (e.g., r ! 6–(1) = 5 rating, s ! 6–(2) = 4 rating).
requires significant consideration for the efficiency of communication. The reliability and validity of GICA were demonstrated in this study. However, the results are limited because the study was conducted mostly in large cities of Korea and therefore did not reflect the trends of rural communities. Therefore, follow-up study must be done to cover the elderly in small medium cities and rural areas, and to investigate the differences of communication ability according to gender, age, years of education and hearing impairment. In addition, the application of GICA to middle-aged individuals will enable identification of the sub-domain that exhibits the first decrease before the elderly period. References Brod, M., Stewart, A.L., Sands, L., et al., 1999. Conceptualization and measurement of quality of life in dementia: the dementia quality of life instrument (DQoL). Gerontologist 39, 25–35. Burzynski, C.M., 1987. The voice. In: Muelle, H.G., Geoffrey, V.C. (Eds.), Communication Disorders in Aging. Gallaudet University Press, Washington, pp. 214–237. Christensen, K.J., Multhaup, K.S., Nordstrom, S., et al., 1991. A cognitive battery for dementia: development and measurement characteristics. Psychological Assessment 3 (2), 168–174. Fehring, R.J., 1987. Methods to validate nursing diagnoses. Heart and Lung 16, 625–629. Frattali, C.M., Thompson, C.K., Holland, A.L., Wohl, C.B., & Ferketic, M.M., 1995. American Speech Language Hearing Association Functional assessment of communication skills for adults (ASHA FACS). Rockville, MD: American Speech-Language-Hearing Association.
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