Australas J Ageing. 2021;00:1–7. wileyonlinelibrary.com/journal/ajag © 2021 AJA Inc.
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1R E S E A R C H A R T I C L E
Psychometric assessment of the Bahasa Malaysia version of the Older Americans Resources and Services- Instrumental Activities of Daily Living
Alexander Lourdes Samy
1,2,3| Shahrul Bahyah Kamaruzzaman
1| Karuthan Chinna
4|
Bairave Shunnmugam
5| Saroja Krishnaswamy
6| Wah- Yun Low
2,3,71Division of Geriatrics, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
2Centre for ASEAN Regionalism University of Malaya, Kuala Lumpur, Malaysia
3Asia- Europe Institute, University of Malaya, Kuala Lumpur, Malaysia
4School of Medicine, Faculty of Health
& Medical Sciences, Taylor's University, Subang Jaya, Malaysia
5Department of Primary Care Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
6Department of Psychiatry, University of Western Sydney, Sydney, NSW, Australia
7Dean's Office, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
Correspondence
Shahrul Bahyah Kamaruzzaman, Division of Geriatrics, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia.
Email: [email protected] Funding information
University of Malaya Research Grant, Grant/Award Number: UMRG: RP012- 13HTM
Abstract
Objective: This study aimed to determine the psychometric properties of the Bahasa Malaysia (BM) version of the Older Americans Resources and Services- Instrumental Activities of Daily Living (OARS- IADL) questionnaire among older persons in Malaysia.
Methods: The English version of OARS- IADL was translated to BM. The psycho- metric properties of the BM version of OARS- IADL were tested among older per- sons attending a health- care facility.
Results: Two hundred and seventy- one older persons participated in the study. The mean age of participants was 67.7 ± 6.1 years. Internal consistency of the items was good (Cronbach's alpha, >0.7). Exploratory factor analysis revealed a single dimension with item factor loadings of >0.5. Confirmatory factor analysis results confirmed a single- factor model (AVE > 50%, CR > 0.7 and CR > AVE).
Conclusion: The BM version of the OARS- IADL questionnaire is a valid and relia- ble instrument that can be used to assess the IADL among older persons in Malaysia.
K E Y W O R D S
activities of daily living, aging, functional status, Malaysia, validation study
Policy Impact
With rapid population ageing occurring globally, especially in Asia- Pacific countries, assessment of the independence in activities of daily living (IADL), among older per- sons, remains as a pivotal measure of successful ageing. A cross- culturally adapted, reliable and valid instrument is needed to measure and understand the IADL status of older persons to refine policies and strategies to combat ageing- related issues.
Practice Impact
This study carves the pathway for researchers, especially from the Asia- Pacific re- gion, to select lingua- cultural adaptation and validation tools to measure and under- stand the IADL status among older people population in their respective countries.
1 | INTRODUCTION
One of the major concerns of developed and developing nations is population ageing. By the year 2030, it is esti- mated that almost 2 billion people, or 22% of the world's population, will be 60 years old and above.1 The lifespan of older persons has increased over time due to better health care. Alongside increasing life expectancy, increase in non- communicable diseases, health- care utilisation and decline in quality of life as well as functional limitation have been reported among older persons.2 One of the most important measures of successful ageing, according to bio- medical and psychosocial experts, is independence in ac- tivities of daily living, which requires both high levels of physical and cognitive functioning, and enables an older person to live independently and engage in community- based activities.2 Activities of daily living are divided into two categories: the basic activities of daily living (BADL) and the more complex instrumental activities of daily liv- ing (IADL). BADL evaluates the capability pertaining to basic functioning; meanwhile, IADL concerns the ability to live in the community.1 In most communities, IADL is deemed a more important measure of successful ageing, compared to BADL.
To perform IADL, one needs to have higher level of cognitive function, such as attention, memory and execu- tive function, and therefore, IADL are more complex than BADL.3 IADL include activities such as travelling, grocery shopping, meal preparation, handling finance, telephone use, housework and management of medication, activities which are deemed important for older persons to continue to live independently and essential for a better quality of life and health outcome.2
The Older Americans Resources and Services- Instrumental Activities of Daily Living (OARS- IADL) is a well- known and well- established tool for assessing IADL among older persons. It is a series of adaptations made from the Lawton and Brody IADL scale.4 The OARS- IADL be- longs to the subset under the activities of daily living domain from the OARS multidimensional functional assessment questionnaire (OMFAQ).5 The OMFAQ contains five do- mains, namely social resources, physical health, mental health, economic resources and activities of daily living (assessing BADL and IADL).5 The OMFAQ has been trans- lated into several languages, such as Dutch, Italian, Austrian, Brazilian, Spanish, Portuguese and Persian and been found to have good validity and reliability.6
Questions pertaining to OARS- IADL are a subset of the activities of daily living domain in the whole of OMFAQ.
The tool assesses 7 items of IADL, such as the ability to use the telephone, handling finances, responsibility for one's own medication, travelling, housekeeping, meal preparation and shopping.5 There are a few advantages of
the OARS- IADL instrument. First, all the items are ap- propriate for both men and women, whereas the Lawton and Brody IADL assessment has recommended to exclude three of the eight tasks, namely meal preparation, house- keeping and laundry, for men.7 Second, the OARS- IADL instrument can be either self- administered or administered by a trained enumerator who has at least high school edu- cation. Third, the assessment of performance level is con- sistent across all questions, which indicates that a task can be performed without any help, some assistance is needed to perform a particular task or the task cannot be performed at all. Older people can make this three- level distinction reliably.4,5 Scoring of the OARS- IADL is rated on a 3- point scale: able to do the activity without any help (2), able to do the activity with some assistance (1) and totally depen- dent and always need assistance to perform the activity (0), with the total score ranging from 0 to 14.5
In Malaysia, a developing country in the South East Asia, the population aged 60 years and above is estimated to dou- ble from 7.7% in 2010 to 14.7% by 2030.8 As of 2019, the number of people aged 65 years and above was 2.23 mil- lion, or 6.82% of the total population. In addition, a three- fold increase in the old- age dependency ratio was expected, from 7.4 in the year 2010 to 21.7 by the year 2040.9 This old- age dependency is influenced by cognitive decline and dementia as shown in a recent study, where the prevalence of mild cognitive impairment (MCI) among older persons aged
≥60 years in Malaysia was 27.3%.10 This high prevalence of MCI and the old- age dependency ratio certainly warrant fur- ther investigation of IADL among older persons in Malaysia, given IADL involves the use of complex cognitive functions.
As rapid population ageing takes place in Malaysia, various policies and strategies are being developed to promote suc- cessful ageing.11 Since IADL status remains an important in- dicator of successful ageing, IADL measurement is deemed important in studies and research pertaining to ageing.
Malaysia is a multi- ethnic and multicultural country, com- prised of three major ethnic groups: the Malay, Chinese and Indian, as well as Others.8,12 Bahasa Malaysia is the coun- try's official and national language and is widely used as the medium of communication across all the ethnic groups.13 A cross- culturally adapted, reliable and valid tool is therefore needed to measure IADL status among this heterogeneous older population. In addition, as the OARS- IADL question- naire has already been translated and validated in several other languages, this provides an avenue for a cross- national comparison of the IADL status of older Malaysians com- pared to those from other countries. Since the OARS- IADL questionnaire has not been translated into Bahasa Malaysia and validated in the local cultural setting, this paper aims to report on the validation process of the translated Bahasa Malaysia version of OARS- IADL for use with the multicul- tural Malaysian population.
2 | METHODS
2.1 | Participant recruitment
An initial pilot study was conducted prior to the main study, with 30 community- dwelling older adults who visited the outpatient clinic at the University of Malaya Medical Centre (UMMC), Kuala Lumpur, for their periodical health check- up. This was conducted to determine whether the instrument being tested was comprehensible and easy to administer. In the final study, 307 participants from the same population pool were targeted. According to Kline,14 for non- complex structural models, a minimum sample size of 200 is adequate.
The inclusion criteria were: older persons aged 60 years and above, who could speak and comprehend Bahasa Malaysia and were not diagnosed with dementia. This information was obtained from the medical records of the participants.
Study participants were recruited using a convenience sam- pling method. Older persons who were waiting for their consultation with the doctors were approached and briefed about the study. Information on their socio- demographic characteristics, medical condition and lifestyle behaviours was obtained from their medical records upon consent. The Montreal Cognitive Assessment (MoCA) was used to screen for MCI, based on a score <23.10 Among those who con- sented to participate in the study, the questionnaires were either self- administered or completed with the assistance of enumerators.
2.2 | Questionnaire translation
The OARS- IADL instrument was first translated from its original English language version to Bahasa Malaysia by a linguist proficient in both languages. The Bahasa Malaysia version was then back- translated by another linguist into the English language. The original English version and the back- translated English version of the OARS- IADL were then compared, and the accuracy in translation and language was checked. No discrepancies were found between the two versions. The psychometric properties of the translated ques- tionnaire were assessed for reliability (internal consistency) and validity (exploratory factor analyses and confirmatory factor analyses).
2.3 | Internal consistency
A pilot study was conducted to assess internal consistency of the items in OARS- IADL questionnaire. In the analy- sis, Cronbach's alpha value, inter- item correlations (IIC) and corrected item- total correlations (CITC) were checked.
Cronbach's alpha values between 0.50 and 0.69 are considered
acceptable, and values between 0.70 and 0.90 are considered to be very strong.15 IIC values between 0.3 and 0.9 and CITC values >0.3 are considered acceptable norms.16
2.4 | Face validation—
pretesting of the instrument
The translated OARS- IADL instrument was pretested to de- termine whether the study participants could understand and comprehend the questions in instrument. The pretest was conducted among 30 older persons who attended the pri- mary care clinic at the University of Malaya Medical Centre (UMMC), Kuala Lumpur. At the end of the session, the par- ticipants were asked whether they could understand the items and whether the instructions, questions and responses were clear. They were also asked whether there were any words or phrases that were difficult to understand or confusing, in order to measure the appropriateness of the instrument.
Modifications were done based on their feedback.
2.5 | Content validation
Content validity was assessed by a panel of experts to deter- mine to what extent the items in the Malay- translated OARS- IADL adequately measured the IADL domain. The content validity index (CVI) approach was used to assess the con- tent validity. Two types of CVI, item- level CVI (I- CVI) and scale- level CVI (S- CVI), were computed.17 The expert panel, comprising a geriatrician, a clinical psychologist and a public health physician, rated each item's relevance to the domain being measured on a 4- point Likert scale. I- CVI is computed as number of experts rating 3 or 4 divided by total number of experts. S- CVI is computed as number of items given rating of 3 or 4 divided by the total number of items. Initially, the I- CVI values for questions 2, 3, 5 and 6 were less than 0.78.
However, after modifications to the questions, the values were more than 0.78. In final analysis, both the I- CVI and S- CVI were more than 0.78. Based on Lynn (1986),18 for a panel with fewer than 5 experts, I- CVI and S- CVI values of more than 0.78 indicate adequate content validity.
2.6 | Exploratory factor analyses
Exploratory factor analyses (EFAs) were used to explore the underlying structures in the items in the OARS- IADL ques- tionnaire. EFA is generally used to determine the number of latent variables that underlie a set of variables.19 In this study, EFA was used to test the hypothesis that the 7 items in OARS- IADL questionnaire belonged to a single dimen- sion. In the analysis, the principal axis factoring method was
used in extraction, as the indicators were reflective in nature.
Adequacy of factor model was tested using Kaiser- Meyer- Olkin (KMO) and Bartlett's test of sphericity. Normally, a KMO value of >0.6 and a significant Bartlett's value are con- sidered to indicate modelling adequacy. Convergence valid- ity was determined by average variance extracted (AVE) and individual item factor loadings. A minimum AVE value of 50% and a minimum factor loading value of 0.5 are the pre- ferred norms.20,21
2.7 | Confirmatory factor analysis
Confirmatory factor analysis (CFA) was used to test the good- ness of fit of a single- factor model for the 7 items in OARS- IADL. In testing the model fit, chi- square/df ratio, comparative fit index (CFI), Tucker- Lewis index (TLI) and root mean square error approximation (RMSEA) threshold values were used. For an acceptable model fit, chi- square/df ratio must be
<3, CFI and TLI values must be >0.9 and RMSEA value must be <0.08.14,22- 23 For sufficient convergence, the average vari- ance extracted (AVE) must be >50%, the composite reliability (CR) must be >0.7 and CR must be >AVE.24
2.8 | Data analyses
Reliability and exploratory factor analyses were performed using Statistical Software for Social Sciences (SPSS), version 21. For CFA, the analysis of a moment structures (AMOS) software was used.
2.9 | Ethics consideration
Ethical approval was obtained from the University of Malaya Medical Centre Ethics Committee (MEC ID No.: 201311- 0483) and National Medical Research Register (NMRR ID No.: 14- 455- 19405). Written or verbal informed consent was obtained from all study participants.
3 | RESULTS
In the pretest, the participants did not report any difficulties in understanding the instructions, questions or responses. Hence, the Bahasa Malaysia version of OARS- IADL questionnaire demonstrated good face validity. It took about 8- 15 minutes for study participants to complete the questionnaire.
In reliability analysis, using data from the 30 participants from the pilot study, the items in the Bahasa Malaysia ver- sion of OARS- IADL showed good internal consistency. The Cronbach's alpha value was 0.82, the inter- item correlation
values ranged between 0.53 and 0.81, and the corrected item- total correlations (CITC) values were between 0.45 and 0.84 (Table 2).
In the final data collection, out of the 307 participants approached, 271 agreed and consented to participate in this study (response rate: 88.3%). Table 1 shows the socio- demographic characteristics of the participants. The mean age of the respondents was 67.7 ± 6.1 years, 72.0% were males, 38.0% were Malays, 51.7% had secondary school education, 80.8% were married and 74.9% resided with their spouses.
Just over one third of them had monthly household income of RM 1001- RM 3000 (45.0%). In Malaysia, the proportions of men and women are similar and about 60% are Malays.
Most of the aged Malays live in rural areas. This study was conducted in an urban health facility.
In EFA, the Kaiser- Meyer- Olkin (KMO) measure of sam- pling adequacy was 0.82 and the P- value for the Bartlett's test of sphericity was <0.001, a single- factor was extracted, the AVE value was 55%, and the factor loadings were between 0.61 and 0.94 (Table 2).
TABLE 1 Socio- demographic profile of participants
Demography n %
Age (y) mean ± SD 67.7 ± 6.1
Gender
Male 195 72.0
Female 76 28.0
Ethnicity
Malay 103 38.0
Chinese 91 33.6
Indian 77 28.4
Education level
Informal schooling 6 2.1
Primary school level 41 15.2
Secondary school level 140 51.7
Tertiary education level 84 31.0
Marital status
Married 219 80.8
Never married 14 5.2
Widow/widower 38 14.0
Living arrangement
Spouse 203 74.9
Children/Siblings 44 16.2
Alone 24 8.9
Household income
≤MYR 1000 78 28.8
MYR 1001- MYR 3000 122 45.0
MYR 3001- MYR 5000 38 14.0
>MYR 5001 33 12.2
Confirmatory factor analysis (CFA) indicated that a single- factor model was acceptable (chi- sq/df = 1.35, TLI = 0.99, CFI = 0.99, RMSEA = 0.03) (Figure 1).
4 | DISCUSSION
This study assessed the psychometric properties of the translated OARS- IADL (Bahasa Malaysia) version, as a subset from the overall activities of daily living domain in the OMFAQ questionnaire. In the original validation of the OARS- IADL study, the discriminant and predictive validity was performed, but the factor structure was not explored.4
The objective of the current study was to assess the psy- chometric properties (construct validity and internal consis- tency) of the OARS- IADL questionnaire. However, items 2, 3, 5 and 6 showed low I- CVI value. As these items are rele- vant for assessing the older persons' IADL, they were modi- fied following the Malaysian cultural norms, using words and phrases that community members would be more familiar with. Utilisation of the back translation method ensured that the instrument has achieved idiomatic, semantic, experiential
and conceptual equivalency between the original and trans- lated version of the OARS- IADL.25 Falahati et al6 followed a similar procedure, which is to maintain some items after some modifications were made according to the Iranian culture.
In reliability analysis, the Cronbach's alpha value was more than .7, indicating that the Bahasa Malaysia version of the OARS- IADL questionnaire has good internal consis- tency.15 This was similar to other previous studies.5,26
The results from the EFA supported the unidimensional property of the items in the questionnaire. This was in line with the hypothesis that the seven items measure a single construct, which is the IADL.4,5 Compared to other items, items 2, 3, 4 and 7 had lower factor loadings.
Item 2 denotes travelling, which is walking from one place to another without taking any transportation. The study was conducted at a primary care clinic in an urban setting, so the majority of the participants in this study would have used transport (either own or public) to get from one place to an- other. According to the report by the Transport Statistics in Malaysia for the year 2018, highest traffic and public trans- port use was observed in urban cities in Kuala Lumpur and Selangor compared to other states.27 Item 3 measures the
TABLE 2 Results from reliability analysis (n = 30) and exploratory factor analysis (n = 271) Item Item description Cronbach’s
Alpha Corrected item- total
correlation Highest value of the inter-
item correlation Factor loading in EFA
1 Ability to use telephone 0.80 0.68 0.82 0.78
2 Travelling 0.82 0.45 0.53 0.51
3 Shopping 0.81 0.52 0.53 0.58
4 Meal preparation 0.81 0.53 0.70 0.58
5 Housekeeping 0.80 0.79 0.75 0.86
6 Ability to manage
medication 0.79 0.84 0.75 0.95
7 Ability to handle finances 0.82 0.51 0.58 0.58
FIGURE 1 Single- factor model for Bahasa Malaysia version of the OARS- IADL
ability to shop for one's own needs and clothing. In Malaysia, most of the needs of an older person are usually taken care of by their children or a caregiver, as the Malaysian culture adheres to values which lean towards the cultural construct of filial piety. This has been ingrained among Asian families, including Malaysians, that they have to take care of their own family's needs. Older parents customarily rely on their chil- dren for social support and care. The younger generation, in turn, gets to fulfil their religious and filial obligations by pro- viding old- age support.28 Item 4 is about meal preparation. In Malaysia, patriarchal systems are still practised among fami- lies, whereby women are still expected to cook and take care of the house chores and children.29 Since a majority of the study participants were men, probably most of them do not engage in meal preparation since their wives will do it. Item 7 refers to ability to handle finance. To a certain extent, the ma- jority of older persons in Malaysia rely on their adult children for financial, physical and emotional support which accounts for living arrangements and life satisfaction of older people in Malaysia.30 Although Malaysia is a multicultural society, the cultural practices and values with regard to care provision for old- age parents are similar, regardless of cultural background.
In CFA, a single- factor model fit was good. The chi- square/df ratio value was <3,23 and RMSEA value was <0.06.22 In ad- dition, both TLI and CFI values were <0.95 as recommended in the literature.22 The average variance extracted (AVE) was
>50%, the composite reliability (CR) value was >0.7, and CR was more than AVE, indicating sufficient convergent valid- ity. Overall, the results in this study indicate that the Bahasa Malaysia version of the OARS- IADL questionnaire is a reli- able and valid instrument for measuring IADL in the multi- cultural Malaysian population.
The main strength of the study is that it followed a com- prehensive, robust and rigorous method of assessing the psy- chometric properties of an instrument. This pioneering study aimed to explore the factor structure of the OARS- IADL questionnaire, utilising both EFA and CFA. The major limita- tion of the study is that it was carried out in a clinical setting and not in the community. Hence, there is probably also as- certainment bias. We suggest future studies be conducted in a population- based setting, to ensure more generalisable find- ings that will account for the older population in Malaysia and reduce the effect of low factor loading issues for items 2- 4 and 7.
5 | CONCLUSIONS
In the literature, IADL are defined as activities that are im- portant for older persons to continue living in the community, independently. The issue of living independently could vary from one culture to another, hence the tool has been adapted to suit cultural practices of Malaysians. Unlike the physical
activities of daily living, IADL are complex and require higher level of cognitive functioning and therefore importance should be given for routine IADL assessments in order to screen if an older person could live independently in the community.
The results from this study confirm the newly developed OARSIADL Bahasa Malaysia version as a reliable and valid tool to measure the IADL among older persons in Malaysia.
The short time needed for its administration makes it a suit- able instrument to be included in clinical settings as well as for research purposes among the older people. This questionnaire should be included when evaluating health, quality of life and functional abilities of older persons. Routine IADL screening would enable early diagnosis and lead to recommendation/
provision of preventive measures and interventions tailored specifically for the vulnerable older persons, especially for those from socio- economically disadvantaged regions. This would improve their functional capacity, promote independ- ence and ensure the well- being and quality of care of older persons.
ACKNOWLEDGEMENTS
The authors would like to thank the University of Malaya Research Grant [UMRG: RP012- 13HTM] for providing fund- ing for the study, as well as the staffs and patients of the Primary Care Clinic, University of Malaya Medical Centre (UMMC).
CONFLICTS OF INTEREST No conflicts of interest declared.
ORCID
Alexander Lourdes Samy https://orcid.
org/0000-0001-5085-4563 Karuthan Chinna https://orcid.
org/0000-0002-2035-344X
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How to cite this article: Samy AL, Kamaruzzaman SB, Chinna K, Shunnmugam B, Krishnaswamy S, Low W- Y. Psychometric assessment of the Bahasa Malaysia version of the Older Americans Resources and Services- Instrumental Activities of Daily Living.
Australas J Ageing. 2021;00:1– 7. https://doi.
org/10.1111/ajag.12958