Background
Ageing is usually associated with a lot of health challenges [
1‐
3]. Falls and fear of falling are some of such challenges that may have serious pervasive effects among older adults [
4,
5]. Fall, defined as an event in which the individual inadvertently comes to rest on the ground or lower level against his will, is a public health issue among older adults [
6,
7]. It is generally estimated that one in three older adults suffers a fall yearly [
6] and prevalence rates of 19 to 27.8% had been reported among Nigerian older adults [
8,
9]. One in five falls among older adults causes serious injuries (such as fractures or head injuries), thereby making falls one of the most common causes of hospitalization and death in this group. This implies that falls have an excessive bearing on health care expenses worldwide [
10,
11]. Apart from the physical and financial burden, fall is also reported to have significant psychological and social consequences, with many older adults who had experienced a fall becoming apprehensive or fearful of fall [
4].
Fear of falling, described as the ongoing concern about falling that ultimately limits the performance of daily activities, is highly prevalent among community-dwelling older adults [
4], and tends to be even higher among those that have experienced fall or that are under institutionalized care. The prevalence of fear of falling varies across communities and societies with rates of 34.4, 35, 43.3 and 95.2% having been reported among populations in Nigeria, Europe, Japan and Brazil respectively [
9,
12‐
14]. An FOF prevalence of 81% had also been reported in a Nigerian stroke sample [
15] suggesting that along with age, the presence of any co-morbidity that is likely to interfere with balance may heighten the likelihood of FOF. Fear of falling (FOF) is a common consequence of falls that can lead to a lot of physical and psychological problems among older adults [
16]. It has been associated with limitation and/or reduction in the performance of activities of daily living, mobility, physical capability, mental health, balancing activities and quality of life, and increased institutionalization [
1,
9,
10,
17]. Fear of falling is suggested to be a potential health problem of equal importance to a fall or may even be a more pervasive and serious problem than actual falls in older adults [
18,
19]. Consequently, FOF is routinely investigated in older adults and several instruments have been developed for its measurement.
The Falls Efficacy Scale (FES) is one of the most common instruments for assessing fear of falling [
20]. In a bid to improve the instrument, four more items were added to the FES to produce a 14-item valid and reliable Modified Falls Efficacy Scale (MFES) [
21] which had since gained popularity in literature. The MFES, like other FOF measures, was originally produced to assess FOF in developed countries. As a result, it may not be entirely suitable for use in developing countries due to cultural and environmental differences between the two categories of countries [
22]. According to Beaton et al. [
22], for an instrument to be used in a new language, setting, culture and environment, it must be cross-culturally validated in order to ensure semantic, idiomatic, conceptual and experiential equivalences between the original and the target populations.
When faced with the problem of unavailability of environment- and culturally-specific outcome measures for assessing a particular construct in a particular setting, stakeholders are usually faced with two options: development of an entirely new scale or cross-culturally adapting the existing scale to suit the new setting. It is usually better to cross-culturally adapt an existing scale than developing a new instrument as cross-cultural adaption is more economical and allows for comparison across populations and locations [
22,
23]. Cross-cultural adaption usually includes initial translation, synthesis, back translation, expert committee review, pilot testing and psychometric evaluation [
22,
24]. With the Nigerian adult literacy in English language standing at 42.1% [
25], many Nigerian older adults will not be able to complete the original English versions of the MFES and other FOF scales. This may introduce bias in assessing FOF among Nigerian older adults as no Nigerian-adapted FOF scale is readily available. Mere translating the instruments to this group of participants by different assessors will equally introduce some biases as the translations are not validated and may vary markedly with individuals. This study was therefore designed to cross-culturally adapt and validate the MFES among Igbo older adults in Nnewi North Local Government Area.
Discussion
The present study was designed to cross-culturally adapt and validate the Igbo version of the Modified Falls Efficacy Scale among Igbo older adults in Nnewi North Local Government Area. In order to ensure accuracy and reduction of bias, the procedure for this study followed the established guidelines for cross-cultural adaptation and validation of pen and paper instruments [
22]. During the process of translating the original English version of the MFES into Igbo version (I-MFES), minimal difficulty was encountered in achieving an acceptable translation. All the items on the MFES were considered by the expert panel to be relevant for measuring level of fear of fall among Igbo speaking older adults. However, few modifications were made in order to ensure semantic, experiential and conceptual equivalence of the terms and examples in Igbo environment. The terms “cabinets” and “closets” in item 8 had no Igbo equivalent terms and were replaced with an Igbo equivalence of “cupboard”. Beaton et al. [
22] suggested that during cultural adaptation of pen and paper instrument, equivalence of the old instrument in the new culture should be ensured. After this adaptation, the I-MFES was then pretested on 30 older adults who were also engaged in cognitive debriefing interview. There was a general consensus of clarity and ease of understanding of all the 14 items among the participants who engaged in cognitive debriefing interview. Hence all items were adopted as suggested in literature [
22]. All these suggest that the translated version is a good equivalence of the original instrument.
Consequently, the I-MFES may be used in place of the E-MFES among Igbo-speaking older adults, irrespective of where they might be found. Generally, the Igbos dwell in the South-east Nigeria but have migrated to many other parts of the world. However, they have always maintained a core linguistic pattern anywhere they find themselves. Even though the Igbo language consists of various dialects, it maintains a central cultural and linguistic pattern which is well understood by most Igbo language speakers. The MFES has been translated into various languages (e.g. German [
29], Dutch [
20], and Serbian [
40]. As directed in literature, these translations are used in place of the original English version in these places and anywhere the speakers of these languages are found. In the same vein, the I-MFES can be used in place of the E-MFES on any Igbo speaker that is most comfortable with Igbo Language irrespective of where they reside.
The correlation coefficient of the relationship between sum scores on the I-MFES and the FES-I demonstrates that I-MFES has excellent convergent validity. This implies that the two instruments (the I-MFES and the FES-I) assess the same construct which is FOF. The I-MFES exhibited excellent internal consistency shown by a Cronbach’s alpha value of 0.97 which falls within the acceptable range. The Cronbach’s alpha value of 0.97 is similar to previously reported values in Serbian (0.98) [
40], French (0.94) [
41] and Chinese (0.90) [
42] versions of the MFES. This finding indicates that the items on the I-MFES are homogenous and internally consistent and that each is assessing different aspects of the construct (FOF) being evaluated. The MDD of the I-MFES reported in this study will be useful in the future in knowing when there is a significant change in FOF of older adults, for instance following an intervention.
Factor analysis is intimately involved with the question of validity, and it is the center of the measurement of psychological constructs [
31,
43]. It provides a diagnostic tool to evaluate whether the collected data are in line with the theoretically expected pattern, or structure of the target construct and thereby determine if the measures used have indeed measured what they are purported to measure (construct validity). Principal component analysis was chosen as against the exploratory factor analysis because of the fact that the scale has already been established on an existing theory by the original authors of the English version [
43]. The data met all the criteria for PCA. The Kaiser-Meyer-Olkin value was within the acceptable limit of greater than 0.6. The KMO values below 0.6 should have led to either collection of more data or a rethink of which variable to include. The Barlett’s test of sphericity also revealed that significant correlation exists in the random matrix. These findings suggest that the I-MFES is a good measure of FOF, and that it measures FOF just as good as the E-MFES in the sampled population. PCA revealed that the I-MFES has only one component similar to what obtained in the original English version. This shows that the I-MFES has only item and total scores without a domain score.
The study is not without limitations. Participants of the present study were recruited from a single community rather than from diverse communities all over Igbo land. We however reasoned that the use of the central Igbo language commonly understood by all will play a big role in minimizing the effect of the recruitment bias. Furthermore, native speakers of English language who were also fluent in Igbo language could not be found to back-translate the harmonized Igbo version of the MFES into English language. The services of lecturers in Physiotherapy who were very fluent in both languages, and were equally very experienced with cross-cultural adaptation were employed. It is believed that their experience in cross-cultural validation would have ensured qualitative translation process.
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