Development of the life change adaptation scale for family caregivers of individuals with acquired brain injury.

AIM: Life changes due to the sudden onset of acquired brain injury (ABI) are drastic personal and social changes that require adaptation and are also an important indicator of the quality of life of family caregivers. However, there are no instruments for evaluating life change adaptation among family caregivers of individuals with acquired brain injury. This study aimed to develop the Life Change Adaptation Scale (LCAS) for family caregivers of individuals with ABI and examine its reliability and validity.
METHODS: A cross-sectional study was conducted using a self-reported questionnaire. A total of 1622 family caregivers of individuals with ABI who belonged to 82 associations for families of individuals with ABI were selected as eligible participants. The construct validity was evaluated using a confirmatory factor analysis. Internal consistency was calculated using Cronbach's alpha. The K6 was also administered to assess the criterion-related validity of the LCAS.
RESULTS: In total, 339 valid responses were received. The confirmatory factor analysis identified eight items from two domains, "Changes in the appraisal of caregiving resources" and "Changes in the health belief as a caregiver" (goodness of fit index = 0.963, adjusted goodness of fit index = 0.926, comparative fit index = 0.986, root mean square error of approximation  = 0.043.) Cronbach's alpha was 0.84. The LCAS was negatively correlated with the K6 (r = -0.504; P<0.001).
CONCLUSIONS: The LCAS is a brief, easy-to-administer instrument that is reliable and valid for family caregivers of individuals with ABI. This study contributes to the assessment and identification by family caregivers of individuals with ABI who require aid in adapting to life changes. Further research should be undertaken to verify the predictive value in a longitudinal study and to attempt to apply the LCAS to assess a broader range of subjects in a wider range of settings.

Introduction

Acquired brain injury (ABI), is defined as damage to the brain that occurs after birth and that is not related to a congenital disorder or degenerative disease [1, 2]. In Japan, ABI cases with cognitive and behavioral dysfunction are defined as “Higher brain dysfunction” [3]. ABI is an unforeseen condition with physical, cognitive and psychosocial deficits that significantly impact upon a person’s ability to live a productive life, including increased aggression, poor memory, concentration difficulties and speech impairments [2, 4, 5]. ABI is most commonly attributed to traumatic brain injury (TBI) or stroke. In 2016, over 27.1 million new cases of TBI were reported worldwide, representing a 3.6% increase from 1990 [6]. In the same year, almost 69 million individuals worldwide were estimated to suffer from residual disabilities due to TBI [6]. In 2016, over 13.7 million new cases of stroke were reported worldwide, representing an 8.1% decrease from 1990 [7]. The incidence of stroke rapidly increases with age, doubling for each decade after age 55 [7, 8]. In the same year, almost 116.4 million individuals worldwide were estimated to suffer from residual disabilities due to stroke [7]. The overall burden of ABI in terms of the absolute number of people affected by ABI or who remained disabled due to ABI has increased across the globe [9].

The families of individuals with ABI play a substantial role in their support after acute hospitalization [10]. In Japan, approximately 90% of individuals with ABI are living with and require daily support from their family [3]. Thus, families of individuals with ABI assume the responsibility of long-term caregiver. Accumulated evidence indicates that the family caregivers of individuals with ABI experience negative health impacts, such as a high level of burden, anxiety, depressive symptoms and poor mental health and quality of life in association with the long length of time spent providing care [11-15].

There is international recognition of the need for psychosocial interventions to improve the quality of life of family caregivers. Several instruments measuring the outcomes of family caregivers were developed to identify family caregivers who are in need of intervention and were used to assess interventions [16]. However, there is substantial diversity in the outcomes, even after ABI. The main focus of previous studies and measures for family caregivers concerning individuals with ABI has been to identify the negative outcomes of the onset of ABI [17]. However, the family caregivers of individuals with ABI can experience not only negative adaptations to life changes but also positive adaptations following the onset of ABI, and such positive life change adaptations are just one of the benefits these individuals can achieve. Measuring the life change adaptations makes it possible to evaluate family caregivers of individuals with ABI and the health services offered by health professionals. It can also improve the quality of life for both the family caregivers of individuals with ABI and other members of their family, even if the individual with ABI has a severe disability.

In 1999, Bakas and Champion (1999) constructed the Bakas caregiving outcomes scale (BCOS) for family caregivers of individuals with stroke to assess life change adaptation. Life change when assuming the caregiving role for individuals with stroke is considered to be an adaptational outcome based on Lazarus’ (1991) definitions of social functioning, subjective well-being, and somatic health [18, 19]. Bakas and Champion (1999) found life change adaptation in the family caregivers of individuals with stroke to be negatively related to mental health and positively related to well-being [18]. However, the BCOS cannot be directly applied to ABI. While most strokes occur in older age (≥65 years) [20], most ABIs occur in adult age (16-44years) [21]. While the family caregivers of individuals with stroke are often in older age rather than middle-aged individuals (45-64years) [22], the family caregivers of individuals with ABI are often middle-aged or older. Developmental tasks differ between middle-aged and older individuals. In comparison to older individuals, middle-aged individuals are more frequently confronted with the roles of family control responsibility and the social responsibility, such as marriage, parenting and working to support the family. Thus, the life course and roles of the family caregiver differ between stroke and ABI. Furthermore, family caregivers of adult ABI patients are more likely than those of pediatric ABI patients to have their adaptational outcomes affected [23, 24]. Pediatric ABI patients complete their early childhood development with their disability [25, 26]. In contrast, loss may be felt when dealing with adult ABI patients, as caregivers will be reminded of a time when the patient had normal cognitive and emotional development without disability. Therefore, measuring the life change adaptation of family caregivers of individuals with ABI requires a longitudinal viewpoint with consideration of the long-term adaptational processes after adult ABI.

Atchley (1999) showed that middle-aged and older adults adapt to changes by using strategies to maintain continuity in their lives, both external and internal in the Continuity Theory [27, 28]. Continuity focuses on global external frameworks, including lifestyles, networks of social relationships, and activity profiles, and internal mental frameworks, including the persistence of a psychic structure of ideas, temperament, affect, experiences, preferences, dispositions, and skills, personal goals, or belief systems [28, 29]. The extent of continuity is determined by a here-and-now assessment made by the individual based on their self-remembered past [27]. Therefore, the life change adaptation of family caregivers of individuals with ABI can be explained with the Continuity Theory. The key to improving life change adaptation involves the specific new circumstances in family caregivers of individuals with ABI, the external dimension and the internal dimension. Thus, it is important to develop a new conceptual instrument, “The Life Change Adaptation Scale (LCAS),” for family caregivers of individuals with ABI that considers the life change adaptation a family caregiver experiences—which consist of external dimensions and internal dimensions—to measure, understand, explain and predict life change adaptation and facilitate intervention to help family caregivers of individuals with ABI.

The object of this research is to develop the Life Change Adaptation Scale (LCAS) for family caregivers of individuals with ABI by measuring adaptation to life changes caused by ABI, and to examine its reliability and validity. In this article, “individuals with acquired brain injury” refers to “disabled individuals with cognitive and behavioral dysfunction because of damage to the brain that occurs after birth and that is not related to a congenital disorder or a degenerative disease.” “Family caregiver of individuals with ABI” refers to “a family relative that cares for or assists an individual with ABI in their daily lives.” “Life change adaptation” refers to “the outcome of adaptation to changes in the appraisal of caregiving resources / the health belief of life of family caregivers due to acquired brain injury.”

Methods

Phase 1: Developing the instrument

A first draft of the LCAS was initially developed following a critical review of the relevant literature. Articles were identified in PubMed, Ichushi-Web and PsycInfo according to the theme “life change” in family caregivers of individuals with ABI. The following search terms were used: “caregivers”, “brain injury”, “stroke”, “encephalitis”, “brain tumor”, and “hypoxic ischemic encephalopathy” and along with the MeSH terms, “adult” and “middle aged”. These searches yielded nine articles [18, 19, 30–34]. The inclusion of an article was based on two criteria: 1) the article was related to the research experiences of family caregivers of individuals with ABI; 2) the article was associated with existing life change scales. Based on the literature review and the researchers’ experiences, a first draft of the LCAS was constructed. This first draft contained 22 items.

To ensure the validity of the content of the first draft of the LCAS, ten experts were invited to rate the relevance of each item with regard to its content in relation to life changes in family caregivers of individuals with ABI. The experts were selected from experienced researchers, clinical support staff and family caregivers (two professors, two clinical psychologists, one social worker, and five family caregivers of individuals with ABI who belonged to an association for family caregivers of individuals with ABI). The responses were scored as follows: 1 = completely important, 2 = slightly important, 3 = slightly unimportant, 4 = not important at all. In addition, “unknown” was included to understand the difficulty level of an item. The author revised the wording of each item based on expert opinions (e.g., to avoid double-barreled questions and ambiguous wording). Consequently, the initial LCAS was refined to include fifteen items.

Phase 2: Validating the instrument

Participants and settings

The survey was conducted among 1622 family caregivers of individuals with ABI who belonged to associations for families in Japan and were selected as eligible participants between September 2019 and November 2020. The 82 associations were selected from a list that is publicly available in Japan. Before sending the survey questionnaires, the author sent informed consent letters to the administrators of all associations of family caregivers of individuals with ABI. Thirty-nine associations (47.5%) consented to participate in the study. The survey questionnaires were distributed to each participant by the staff of each association. The study’s inclusion criteria as follows: 1) caring for an individual with ABI, 2) ≥20 years old, 3) a family member of an individual with ABI, and 4) the individual with ABI developed ABI at 16–64 years old. The following exclusion criteria also had to be met: 1) not caring for an individual with ABI, 2) ≤19 years old, 3) not a family member of individual with ABI, 4) the individual with ABI developed ABI at <16 or >64 years old. The reasons for including “the individual with ABI developed ABI at 16–64 years old” and excluding cases in which ABI occurred in an individual at <16 or >64 years old are that adult ABI is not an injury in a stage that progresses with age, like pediatric ABI, and it is not an injury in a stage that declines with age, like ABI in old age, and it is in a stage that is associated with a consistent cognitive and psychosocial function. As a result, the adaptation process and outcomes for ABI are different. Data were collected between September 2019 and January 2020.

Measures

The participants’ demographic characteristics included age, sex, and relationship to an individual with ABI. The individuals with ABIs’ demographic characteristics included age, sex, age at the time of ABI occurrence, cause of ABI, period after ABI, and impairment.

The LCAS was scored on a seven-point Likert scale ranging from -3 (the most deteriorated), to 0 (did not change), to +3 (the most improved).

To assess the concurrent validity of the scale, the participants were also asked to assess each item in the Japanese version of the K6 [35]. This scale consists of six items measuring mental health on a 5-point Likert scale. Each question rated the frequency of distress symptoms. The responses were scored as follows: 0 = none of the time, 1 = a little of the time, 2 = some of the time, 3 = a lot of the time, 4 = all of the time; thus, the total score ranges from 0 to 24. High scores on the K6 indicate a low level of mental health. In this scale, Cronbach’s alpha coefficient was 0.88. The area under the receiver operating characteristic curve of this scale indicated excellent screening ability for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) mood and anxiety disorders [35]. A previous study considered the K6 to be a continuous scale in which higher scores reflect lower levels of mental health [36]. In addition, another study explained that there was a correlation between an adverse impact on caregivers’ mental health and the negative perception regarding life changes [5]. Based on the findings from previous studies, we predicted that mental health deterioration in cases with higher K6 scores reflected negative life change adaptation with lower LCAS scores. Thus, the author used this scale as an indicator of concurrent validity.

Statistical analyses

IBM SPSS ver. 22.0 and Amos 24.0 (SPSS Inc., Chicago, Illinois, USA) were used to perform all statistical analyses.

An item analysis and exploratory factor analysis were conducted to evaluate the reliability and convergent validity of the initial LCAS. The criteria for the item analysis included rate of response difficulty (non-respondents:≥5%), distribution (one answer specific in a seven-point Likert scale: ≥85%), skewness and kurtosis (absolute values of <1.0 each), correlations of each item (correlation coefficient >0.6), a good-poor analysis (no significant differences between the highest scoring and lowest scoring groups), an item-total analysis (correlation coefficient between the item and the total score without that item ≥0.5).

After the item analysis, the total sample was randomly divided into two samples for cross-validation: in group 1, an exploratory factor analysis was performed; and in group 2, a confirmatory factor analysis was performed.

To assess the dimensionality of the LCAS, an exploratory factor analysis (maximum likelihood solution method) with promax rotation was performed on the development sample. Dimensionality was assessed based on eigenvalue >1.0, and a scree plot. Item loading needed to exceed 0.40. A confirmatory factor analysis (CFA) was then conducted to verify the construct validity. The goodness of fit index (GFI), adjusted goodness of fit index (AGFI), comparative fit index (CFI), and root mean square error of approximation (RMSEA) were used to evaluate the data model fit. The model was accepted if the GFI, AGFI, and CFI indices were ≥0.900 and the RMSEA was ≤0.050. Furthermore, criterion-related validity was examined using the K6 total score.

Internal consistency reliability was evaluated by calculating Cronbach's alpha coefficient for the LCAS, with alpha ≥ 0.70 considered acceptable.

Ethical considerations

The Institutional Review Board of the Medical Department of Yokohama City University School approved this study on July 17th, 2019 (No. A190700007). All study participants provided their written informed consent and completed the questionnaire, which was unsigned to ensure the anonymity of the participants. The informed consent form explained the voluntary nature of participation, management of data, and intention to publish the results.

Results

Demographic characteristics

In total, 398 individuals returned the questionnaire and 339 (85.1%) individuals met the criteria for inclusion. A total of 59 families were excluded because the individual with ABI developed ABI at <16 years old (n = 37) or ≥65 years old (n = 8), there was no response (n = 8) or there was no response to the LCAS (n = 6). Tables 1 and 2 shows demographic characteristics. Family caregivers of individuals with ABI ranged in age from 31 to 83 years, with an average age of 63.0 (SD = 10.1). A total of 75.5% of family caregivers were female. Individuals with ABI ranged in age from 21 to 77 years, with an average age of 49.5 (SD = 12.1). A total of 81.1% of individuals with ABI were male. The length of care ranged from 0.5 to 40 years, with an average length of care of 12.4 years (SD = 8.0).

Table 1

Demographic characteristics of family caregivers.

n = 339
		Number or Mean±SDa	% or (Range)
Age (n = 325)		63.0±10.1	(31–83)
	<25	0	0.0
	25–34	2	0.6
	35–44	10	2.9
	45–54	58	17.1
	55–64	103	30.4
	65–74	107	31.6
	75<	45	13.3
	Missing	14	4.1
Age at the time of ABI (n = 320)		51.1±10.0	(19–76)
	16–18	0	0.0
	19–24	3	0.9
	25–34	12	3.5
	35–44	54	15.9
	45–54	143	42.2
	55–64	78	23.0
	65<	30	8.8
	Missing	19	5.6
Sex (n = 332)	Female	256	75.5
	Male	76	22.4
	Missing	7	2.1
Relationship to individual with ABI (n = 335)	Parent	178	52.5
	Spouse	142	41.9
	Son/daughter	1	0.3
	Sibling	13	3.8
	Other	1	0.3
	Missing	4	1.2

aSD: standard deviation

Table 2

Demographic characteristics of individuals with ABI.

			n = 339
		Number or Mean±SD	% or (Range)
Age (n = 338)		49.5±12.1	(21–77)
	<25	6	1.8
	25–34	26	7.7
	35–44	88	26.0
	45–54	97	28.6
	55–64	75	22.1
	65–74	43	12.7
	75<	3	0.9
	Missing	1	0.3
Age at the time of ABI (n = 339)		37.2±14.3	(16–64)
	16–18	32	9.4
	19–24	55	16.2
	25–34	69	20.4
	35–44	62	18.3
	45–54	73	21.5
	55–64	48	14.2
	65<	0	0.0
	Missing	0	0.0
Sex (n = 338)	Female	63	18.6
	Male	275	81.1
	Missing	1	0.3
Period after ABI (years) (n = 338)		12.4±8.0	(0.5–40)
	<1	2	0.6
	1–3	40	11.8
	4–6	55	16.2
	7–9	50	14.7
	10≦	191	56.3
	Missing	1	0.3
Cause of ABI (n = 339)	Trauma to the head	174	51.3
	Stroke	144	42.5
	Tumor	13	3.8
	Anoxia	17	5.0
	Infection	15	4.4
	Other	1	0.3
Impairment (n = 338)	Attention	303	89.6
	Problem solving	303	89.6
	Memory	278	82.5
	Language	139	41.1
	Spatial awareness	81	24.0
	Physical awareness	40	11.9
	Disease awareness	39	11.6
	Apraxia	93	27.6
	Topographical	130	38.6
	Behavioral control	202	59.9

aSD: standard deviation

Item analysis

Table 3 shows the item analysis results. Item 8 was excluded according to the item-total analysis. The correlation coefficient between item 2 and 9 was higher than 0.6. Item 2 was excluded according to the item difficulty. Thus, an exploratory factor analysis with promax rotation was performed for the thirteen remaining items.

Table 3

Item analysis of “the life change adaptation scale”.

n = 339
No.	Item	Item difficulty a	Population distribution b							Kurtosis / Skewness c		Correlation of item d	Good-Poor analysis e	Item-Total correlation f
			-3	-2	-1	0	+1	+2	+3
1	Your attitude of not trying too hard alone on any issue	3.5	17.4	23.0	21.5	22.1	7.1	5.0	.3	.379	-.553	−	.000**	.508**
2	Your feeling of respect for the person with acquired brain injury	1.2	5.9	13.6	17.1	28.9	17.4	12.1	3.8	-.021	-.587	+	.000**	.559**
3	Your relaxed mind that allows enjoyment of leisure activities and hobbies	0.3	25.4	28.9	24.2	11.5	6.2	2.7	.9	.847	.347	−	.000**	.574**
4	Your mindset of respecting your own health	0.3	9.1	15.0	18.0	19.2	20.9	14.2	3.2	-.073	-.937	−	.000**	.579**
5	Your attitude of being considerate of the circumstances and feelings of others	0.6	2.9	4.4	12.4	23.9	31.0	18.6	6.2	-.460	.038	−	.000**	.573**
6	Your view toward social systems related to health and life for individuals with acquired brain injury	2.9	3.2	6.8	13.6	24.5	29.8	16.2	2.9	-.454	-.160	−	.000**	.671**
7	Your unique approach to relieving stress	0.3	11.8	16.8	28.9	20.1	15.0	5.9	1.2	.209	-.549	−	.000**	.705**
8	Your general impression of people with disabilities	0.6	1.5	2.1	4.4	24.2	28.6	24.5	14.5	-.521	.385	−	.000**	.434**
9	The relationship between you and the person with acquired brain injury	0.9	9.7	10.9	17.1	33.6	13.6	10.3	3.8	-.024	-.444	+	.000**	.558**
10	The relationship between you and family members other than the person with acquired brain injury	0.6	8.0	11.2	18.9	37.8	13.3	7.7	2.7	-.024	-.137	−	.000**	.530**
11	Your attitude of seeking help when needed	0.0	3.8	6.5	11.8	27.4	33.6	12.1	4.7	-.495	.227	−	.000**	.594**
12	Your sense of pride in yourself	0.9	7.4	6.2	15.6	46.6	13.6	7.4	2.4	-.276	.469	−	.000**	.664**
13	Interactions between you and your friends or acquaintances (except for family)	0.9	13.0	15.9	24.5	28.6	10.6	5.9	0.6	.076	-.515	−	.000**	.629**
14	Your sense of responsibility as a member of family	0.6	5.3	4.7	10.6	40.7	16.5	14.7	6.8	-.265	.128	−	.000**	.614**
15	Your outlook on your life going forward	0.9	22.1	24.5	27.7	14.5	6.5	3.8	0.0	.554	-.297	−	.000**	.633**

**: P<0.001

Exclusion criteria of the item analysis

a: The percentage of no answers was over 5% of the sample.

b: Item with a score (-3 to +3) of 85% or higher in the sample.

c: Absolute value of skewness or kurtosis was less than -1 or greater than 1.

d: Correlation was over 0.6.

e: Difference in the average score between the highest scoring group and the lowest scoring group is not a significant difference (P≥0.05).

f: The correlation coefficient between the item and the total of all the items (but with exception of the item) has a correlation coefficient of 0.5 or lower.

Factor structure

Table 4 shows the factor loading for the exploratory factor analysis. The development model yielded eight items in two factors with eigenvalues and a scree plot. In our interpretation, factor I included four items (5, 6, 11, 14) interpretable as “Changes in the appraisal of caregiving resources” for family caregivers of individuals with ABI. Factor II included four items (1, 3, 4, 15) interpretable as “Changes in the health belief as a caregiver” for family caregivers of individuals with ABI. The factor loading was >0.40 for each factor. The cumulative contribution of the two factors explained 53.1% of the variance. The correlation coefficient between the two factors was 0.57.

Table 4

Exploratory factor analysis of “the life change adaptation scale”.

n = 170
No.	Item		Factor Ⅰ	Factor Ⅱ	Total scale communality
			Changes in the appraisal of caregiving resources	Changes in the health belief as a caregiver
6	Your view toward social systems related to health and life for individuals with acquired brain injury		0.840	-0.020	0.687
5	Your attitude of being considerate of the circumstances and feelings of others		0.737	-0.028	0.521
14	Your sense of responsibility as a member of family		0.631	0.048	0.436
11	Your attitude of seeking help when needed		0.570	0.092	0.393
3	Your relaxed mind that allows enjoyment of leisure activities and hobbies		-0.175	0.976	0.788
15	Your outlook on your life going forward		0.149	0.624	0.517
1	Your attitude of not trying too hard alone on any issue		0.087	0.601	0.428
4	Your mindset of respecting your own health		0.188	0.564	0.475
Cumulative contribution (%)			42.2	53.1
Factor correlation coefficients (r)		Factor Ⅰ	1.00	0.57
		Factor Ⅱ	0.57

Maximum likelihood solution method with promax rotation.

Missing data were excluded.

Fig 1 shows the factor loading for the confirmatory factor analysis of the LCAS (Fig 1). The model fit showed GFI = 0.963; AGFI = 0.926; CFI = 0.986; RMSEA = 0.043, and nearly satisfied the appropriate criteria in each subject.

Fig 1

Confirmatory factor analysis of “the life change adaptation scale”.

Internal consistency and validity

Table 5 shows internal consistency and validity of the LCAS. Cronbach’s alpha was 0.84 for the total scale and “Changes in the appraisal of caregiving resources” (Factor I) and “Changes in the health belief as a caregiver” (Factor II) were 0.79 and 0.79, respectively. A negative life change adaptation as well as a low LCAS score showed a significant amount of variance between mental health deterioration as well as a high K6 score (r = -0.50; P<0.001).

Table 5

Internal consistency and criterion-related validity of “the life change adaptation scale”.

Factors	Mean (SD a)	The K6 b	Chronbach's alpha
Ⅰ: Changes in the appraisal of caregiving resources	1.7 (4.2)	-0.40*	0.79
	n = 326	n = 312	n = 304
Ⅱ: Changes in the health belief as a caregiver	-4.0 (4.6)	-0.48*	0.79
	n = 324	n = 313	n = 304
Total 8 items	-2.2 (7.7)	-0.50*	0.84
	n = 314	n = 304	n = 304

Pearson’s correlation coefficients between the total score of validity measure of the LCAS

aSD: standard deviation

bThe K6: Japanese version of the K6 (Furukawa et al., 2008)

*: P<0.001

Discussion

Life changes due to the sudden onset of acquired brain injury are drastic personal and social changes that require adaptation and are also an important indicator of the quality of life of family caregivers. However, there are no instruments for evaluating life change adaptation among family caregivers of individuals with acquired brain injury. To the best of our knowledge, the LCAS is the first scale developed for family caregivers of individuals with ABI, which measures life change adaptation caused by ABI. The LCAS demonstrated adequate reliability (Cronbach’s alpha was 0.84) and validity (r = 0.509; P<0.001, between the K6 scale). The dimensionality was confirmed by the CFA, which indicated a good fit (GFI =  0.963, AGFI  =  0.926, CFI  =  0.986, RMSEA  = 0.043). The received response rate was low (20.9%). Furthermore, the demographic characteristics of non-responders were unknown, so the sample may have been biased. However, our response rate was similar to that of a previously published study polling the same population [37]. Regarding the demographics of the family caregivers of individuals with ABI, the caregivers were mostly women (75.5%). The average age at which the individual with ABI developed ABI was 37.2 years (SD = 14.3). According to the official evaluation by the Japanese government and a previous study, this is nearly identical to the profile of participants in the survey on the family caregivers of individuals with ABI [17]. Thus, the sample was deemed representative of the population of family caregivers of individuals with ABI.

The original point is to put forward the new model as opposed to the previous model proposed by Bakas [18, 19] with regard to three points: demonstration among not only the family caregivers of stroke patient, but for several types of diseases associated with ABI, focus on the individuals with ABI who developed ABI from 16–64 years of age and carry out recruitment not from hospitals but from the community. The majority of family members being 55–74 years old and the length of time since the injury being over 10 years were considered to have influenced the findings regarding adaptation. In general, families who have parents in this age range are more likely to have adult children who are no longer dependent. The family caregivers of individuals with ABI must fill the role of caring for an adult who is now dependent after having fulfilled their role of caring for their children. The family caregivers of individuals with ABI therefore need to fill a specific role that most family members never experience. This is likely to influence the adaptation of the family to the circumstances they face in relation to ABI.

The first factor of the LCAS, “Changes in the appraisal of caregiving resources,” consists of four items: “Your attitude of being considerate to the circumstances and feelings of others”, “Your view toward social systems related to health and life for individuals with acquired brain injury”, “Your attitude of seeking help when needed”, and “Your sense of responsibility as a family member.” These items indicate the specificity of changes in familial and social resources which were given and received in order to carry out their daily living by the onset of ABI, such as responsibility for the family caregiver and interacting with social systems. Previous studies have described the changes in the roles to be endemic to family life after ABI [38, 39]. Another study also pointed out that the family adaptation to brain injury represents an effort to bring a new level of functioning to a family [40]. That is, “Changes in the appraisal of caregiving resources” of the LCAS has potential utility for evaluating the changes in new caregiving resources which are needed to adapt to the changing family roles and functions among the family caregivers of individuals with ABI.

The second factor of the LCAS, “Changes in the health belief as a caregiver”, consists of four items: “Your attitude of not trying too hard alone on any issue”, “Your relaxed mind that allows enjoyment of leisure activities and hobbies”, “Your mindset of respecting your own health”, and “Your outlook on your life going forward”. These items indicate the specificity of changes in the belief which reflects perspective on their own health. There is strong evidence that the physical and emotional health of family caregivers of individuals with ABI are affected by the onset of ABI [13, 41–43]. Nonetheless, the strategies for managing their health still remain ambiguous. A previous study suggested that they lacked personal time for self-care even though they were aware that their own health was declining [44]. Although respite care allows caregivers to take some personal time and relax, it has been suggested that psychological characteristics are more important than respite care alone for the family caregiver of individuals with ABI [43]. That is, “Changes in the health belief as a caregiver” of the LCAS has a potential utility for evaluating the changes in new health beliefs that are needed to adapt to the changing health situation among family caregivers of individuals with ABI.

Limitation

The present study was associated with several limitations. First, a total of 75.5% of the family caregivers who participated in this survey, were female, while 81.1% of individuals with ABI were male. This does represent the traditional dynamics [17] but may contaminate assumptions about the meaning of the factors. However, this study design did not allow for a determination of causality between the LCAS response and the gender difference in family caregivers of individuals with ABI. Therefore, further longitudinal studies should be performed to verify the LCAS’s predictive ability.

Second, the survey participants only included individuals who had joined associations of family caregivers of individuals with ABI, and the results may not be generalizable to the national population of family caregivers of individuals with ABI. Further studies should attempt to assess a broader range of subjects in a wider range of settings in order to validate these psychometric analyses.

The LCAS English version.

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The LCAS Japanese version.

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24 Jul 2020

PONE-D-20-15809

Development of the Life Change Adaptation Scale for family caregivers of individuals with acquired brain injury

PLOS ONE

Dear Dr. Shindo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Sep 07 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Manuel Fernández-Alcántara, Ph.D.

Academic Editor

PLOS ONE

Additional Editor Comments:

Dear authors,

Reviewer's have found you manuscript of being of great interest to the field. Please address the commentaries raised by reviewer 1 and also the major revision suggested by reviewer 2 (included in the doc flie attached to this review). We wait for a resubmission of your manuscript.

Journal Requirements:

When submitting your revision, we need you to address these additional requirements.

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

2. In your Methods section, please provide additional information about the participant recruitment method and the demographic details of your participants. Please ensure you have provided sufficient details to replicate the analyses such as: a) the recruitment date range (month and year), b) a description of any inclusion/exclusion criteria that were applied to participant recruitment, c) a table of relevant demographic details, d) a statement as to whether your sample can be considered representative of a larger population, e) a description of how participants were recruited, and f) descriptions of where participants were recruited and where the research took place.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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4. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

**********

5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: This study aimed to develop the Life Change Adaptation Scale (LCAS) for family caregivers of individuals with ABI and to examine its reliability and validity. This reviewer feels that the authors contribute something important to the wellbeing of family caregivers for persons with ABI. With the average length of care delivery being 12 years, a family member’s mental and physical health is paramount. This article a good fit for the PLOS One Journal with some revisions and copy editing.

Those suggestions are as follows:

• The 4 point scale anchors described in the text (1 = completely important, 2 = slightly important, 3 = slightly unimportant, 4 =not important at all) are not the same as appear on the English-language version of the instrument (a 7 point scale from “The most deterioration” to “did not change” to “The most improved”) which is a substantially different instrument than the one described.

• On that note, the factor names for factor 1 does not seem to reflect the items (factor 1=“Changes in the living resources for caregiving” and factor 2=“Changes in the health belief as a caregiver”). Factor one includes ‘Your attitude of being considerate to the circumstances and feelings of others”, “Your view toward social systems related to health and life for individuals with acquired brain injury”, “Your attitude of seeking help when needed”, and “Your sense of responsibility as a family member.”—all of the items seem to assess attitudinal changes and not changes in resources—perhaps changes in APPRAISAL of resources?

• Throughout, there are some minor semantic updates required—all of which are likely attributable to the translation from Japanese.

• The methods overview in the abstract on page 2, line 28-29 doubles uses the word confirmed/confirmatory which adds redundancy. Likewise, in the conclusions overview on page 3, lines 41-42, the first sentence uses “family caregivers of individuals with ABI” twice.

• On page 3, lines 43 and 44, the sentence that reads “This study contributes toward assessing the life change adaptation and identifying family caregivers of individuals with ABI who require intervention.” could be stronger (e.g., this study contributes to the assessment and identification…”)

• On page 5, lines 82-83, the authors note that caregivers of stroke victims are often older age rather than middle age, and that ABI caretakers are often middle aged or older. This is important because the author references the ‘life course and roles of the family caregiver’. It may be useful to define what ‘middle aged’ and ‘older aged’ means in this context.

• On page 8, lines 138-140, there is another repeated use of ‘family caregivers of individuals with ABI’.

• On page 9, line 149, the authors refer to “type of disorder” but they likely mean impairment? In table 2 on page 14, the factors listed range from attention, to topographical, to physical awareness.

• On page 20, lines 286-287, there is a repeated use of the word strong/strongly. On the same page, line 289, the sentence that reads “lacked of personal time for self-care” could better be worded as “lacked personal time for self-care”.

• Page 20, the final sentence ending on line 295, is powerful and a great way to end the paper. The section on limitations that follows should precede that section to maximize impact.

• One other limitation to note is the overrepresentation of female respondents (76%) and male ABI patients (81%)—this does represent the traditional dynamics but may contaminate assumptions about the meaning of the factors.

• In PLOS ONE, the P value should be expressed as a capital P—that change can be made throughout.

Reviewer #2: Dear Authors,

This research will be of great interest to the ABI field. The main issue is that the ABI versus ageing process is not taken into consideration and this has implications for your analysis and the overshadows the likely benefits this measure could have within the ABI field. I would be most interested to read the revised version and encourage you to do this work to enhance the paper.

**********

6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Kim A. Gorgens, Ph.D., ABPP & Hollis Lyman, MA

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Submitted filename: PONE Review June.docx

Click here for additional data file.

Submitted filename: LCAS review.docx

Click here for additional data file.

28 Aug 2020

Thank you very much for your e-mail regarding our manuscript, “Development of the Life Change Adaptation Scale for family caregivers of individuals with acquired brain injury” (PONE -D-20-15809). We are grateful to know that it is potentially acceptable for publication in PLOS ONE. Please find attached a revised version of our manuscript.

Your comments and those of the reviewers were highly insightful and enabled us to greatly improve the quality of our manuscript. We include below our point-by-point responses to each of the comments of the reviewers as well as your own comments.

We look forward to hearing from you regarding our re-submission. We would be happy to respond to any further questions and comments that you may have.

Response to Reviewers

To the comments of Reviewer #1

1. The 4 point scale anchors described in the text (1 = completely important, 2 = slightly important, 3 = slightly unimportant, 4 =not important at all) are not the same as appear on the English-language version of the instrument (a 7 point scale from “The most deterioration” to “did not change” to “The most improved”) which is a substantially different instrument than the one described.

Response: The 4-point scale was used to ensure the content validity of the first version of the LCAS by an expert check, and the 7-point scale was used to measure the life changes in the final version of the LCAS distributed to family caregivers of individuals with ABI.

2. On that note, the factor names for factor 1 does not seem to reflect the items (factor 1=“Changes in the living resources for caregiving” and factor 2=“Changes in the health belief as a caregiver”). Factor one includes ‘Your attitude of being considerate to the circumstances and feelings of others”, “Your view toward social systems related to health and life for individuals with acquired brain injury”, “Your attitude of seeking help when needed”, and “Your sense of responsibility as a family member.”—all of the items seem to assess attitudinal changes and not changes in resources—perhaps changes in APPRAISAL of resources?

Response: As suggested, we have revised the factor names for factor 1 from “Changes in the living resources for caregiving” to “Changes in the appraisal of caregiving resources.”

3. Throughout, there are some minor semantic updates required—all of which are likely attributable to the translation from Japanese.

Response: As suggested, we have now had a professional medical editor whose native language is English proofread the revised manuscript (Japan Medical Communication, Inc.; https://www.japan-mc.co.jp).

The methods overview in the abstract on page 2, line 13-14 doubles uses the word confirmed/confirmatory which adds redundancy. Likewise, in the conclusions overview on page 3, lines 27-28, the first sentence uses “family caregivers of individuals with ABI” twice.

Response: We have carefully corrected the highlighted portion as follows:

Line 13-14

“The construct validity was evaluated using a confirmatory factor analysis.”

Line 27-28

“The LCAS is a brief, easy-to-administer instrument that is reliable and valid for family caregivers of individuals with ABI.”

4. On page 3, lines 43 and 44, the sentence that reads “This study contributes toward assessing the life change adaptation and identifying family caregivers of individuals with ABI who require intervention.” could be stronger (e.g., this study contributes to the assessment and identification…”)

Response: As suggested, we have corrected line 28-29, as follows:

“This study contributes to the assessment and identification by family caregivers of individuals with ABI who require aid in adapting to life changes.”

5. On page 5, lines 82-83, the authors note that caregivers of stroke victims are often older age rather than middle age, and that ABI caretakers are often middle aged or older. This is important because the author references the ‘life course and roles of the family caregiver’. It may be useful to define what ‘middle aged’ and ‘older aged’ means in this context.

Response: As suggested, we have added an explanation concerning what ‘middle aged’ and ‘older aged’ mean in this context (line 81-84).

“Developmental tasks differ between middle-aged and older individuals. In comparison to older individuals, middle-aged individuals are more frequently confronted with the roles of family control responsibility and the social responsibility, such as marriage, parenting and working to support the family.”

6. On page 8, lines 138-140, there is another repeated use of ‘family caregivers of individuals with ABI’.

Response: As suggested, we corrected line 144-145.

“The survey was conducted with 1622 family caregivers of individuals with ABI who belonged to associations for families in Japan and were selected as eligible participants,”

7. On page 9, line 149, the authors refer to “type of disorder” but they likely mean impairment? In table 2 on page 14, the factors listed range from attention, to topographical, to physical awareness.

Response: As suggested, we investigated impairment. We have now revised the text (line 167-168 and table 2).

8. On page 20, lines 286-287, there is a repeated use of the word strong/strongly. On the same page, line 289, the sentence that reads “lacked of personal time for self-care” could better be worded as “lacked personal time for self-care”.

Response: As suggested, we have revised lines 334-336 and 336-338.

9. Page 20, the final sentence ending on line 295, is powerful and a great way to end the paper. The section on limitations that follows should precede that section to maximize impact.

Response: We appreciate the reviewer’s suggestion. The section has been moved to a point after the limitations section (line 317-343).

10. One other limitation to note is the overrepresentation of female respondents (76%) and male ABI patients (81%)—this does represent the traditional dynamics but may contaminate assumptions about the meaning of the factors.

Response: We appreciate the reviewer’s suggestion. The following has now been added to the limitations section (line 305-311):

“The present study was associated with several limitation. First, a total of 76.2% of the family caregivers who participated in this survey, were female, while 81.1% of individuals with ABI were male. This does represent the traditional dynamics [17] but may contaminate assumptions about the meaning of the factors. However, this study design did not allow for a determination of causality between the LCAS response and the gender difference in family caregivers of individuals with ABI. Therefore, further longitudinal studies should be performed to verify the LCAS’s predictive ability.”

11. In PLOS ONE, the P value should be expressed as a capital P—that change can be made throughout.

Response: As suggested, we have corrected this point.

To the comments of Reviewer #2

Background

1. Information about the incidence of strokes across all age groups is not included. These need to be more clearly defined or the statements substantiated with more evidence. This is an important issue as the patients with stroke and their families have been excluded.

Response: The present study included patients with stroke and their families. Information on the incidence of stroke across all age groups is shown in references no.[7]. We have now added text on the incidence of stroke by age (lines 44-45).

“The incidence of stroke rapidly increases with age, doubling for each decade after age 55 [7,8]”

2. Given the argument for caregivers being within a defined age – was a pediatric ABI population considered? If not, then the nature of caring for an adult that was previously independent needs to be included in the background.

Response: As suggested, we have added the nature of caring for an adult that was previously independent needs to be included in the background (line 85-88). In addition, we have added the inclusion and exclusion criteria (line 152-156) along with the reasons for excluding pediatric ABI patients (line 156-162).

Line 85-88

“Furthermore, family caregivers of adult ABI patients are more likely than those of pediatric ABI patients to have their adaptational outcomes affected [23,24]. Pediatric ABI patients complete their early childhood development with their disability [25,26]. In contrast, loss may be felt when dealing with adult ABI patients, as caregivers will be reminded of a time when the patient had normal cognitive and emotional development without disability.”

Line 152-156

“inclusion criteria: 1) caring for an individual with ABI, 2) ≥20 years old, 3) a family member of an individual with ABI, and 4) the individual with ABI developed ABI at 16–64 years old. The following exclusion criteria also had to be met: 1) not caring for an individual with ABI, 2) ≤19 years old, 3) not a family member of individual with ABI, 4) the individual with ABI developed ABI at <16 or >64 years old.”

Line 156-162

“The reasons for including “the individual with ABI developed ABI at 16–64 years old” and excluding cases in which ABI occurred in an individual at <16 or ≥64 years old are that adult ABI is not an injury in a stage that progresses with age, like pediatric ABI, and it is not an injury in a stage that declines with age, like ABI in old age, and it is in a stage that is associated with a consistent cognitive and psychosocial function. As a result, the adaptation process and outcomes for ABI are different.

3. What is the intention of developing this measure? What are the benefits for having such a measure for health services, health professionals and families? The rationale needs to be made clearer for what is missing and what the anticipated benefits.

Response: We appreciate the reviewer’s comments. The following has now been added to the revised manuscript (line 61-69):

“The main focus of previous studies and measures for family caregivers concerning individuals with ABI has been to identify the negative outcomes of the onset of ABI [17]. However, the family caregivers of individuals with ABI can experience not only negative adaptation to life changes but also positive adaptations following the onset of ABI, and such positive life change adaptations are just one of the benefits these individuals can achieved. This measure makes it possible to assess the life change adaptations in the family caregivers of individuals with ABI and of health services by health professionals. It can also improve the quality of life for both the family caregivers of individuals with ABI and other members of their family, even if the individual with ABI has a severe disability.”

Results

4. Why did some families receive the questionnaire that were not eligible?

Response: We have now added an explanation concerning the number of people excluded (line 215-217).

“A total of 59 families were excluded because the individual with ABI developed ABI at <16 years old (n=37) or ≥65 years old (n=8), there was no response (n=8) or there was no response to the LCAS (n=6). “

5. Low response rate – please comment

Response: Because the number of received responses was low, the sample may have been biased. However, the sample was still representative. We have now mentioned this in the revised manuscript (line 290-293).

“The received response rate was low (20.9%). Furthermore, the demographic characteristics of non-responders were unknown, so the sample may have been biased. However, our response rate was similar to that of a previously published study polling the same population [36]. “

6. Co-morbidities? Given the age range of the person with ABI (up to 76 years), were other aspects of health/disability and care required taken into consideration? Difficult to determine how much of the family adjustment process is due in part to the ageing process for the person with the ABI and other family members.

Response: The LCAS was designed under the concept question of “How your life or attitude has changed since acquired brain injury struck your family?”, which can enable a self-assessment focused on ABI by the family. However, given the wide range in the potential age of the person with ABI, other aspects of health/disability and care required should also be taken into consideration. Whether and how ABI family caregivers will be affected by other aspects should be explored in a future study.

Tables 3 and 4:

7. These tables are not legible and therefore the reviewer is unable to make comment.

Response: We apologize for this error and have now revised the tables using the PLOS ONE style templates.

Discussion

8. The discussion needs to address the issues of ABI versus ageing. What was found between the ageing groups? Perhaps the analysis should be more about the comparison of groups by age or groups by time since injury

Response: As mentioned in our response to the sixth comment, we considered this study to be focused on adaptation to life changes for a wide range of ages of family caregivers, based on individuals with ABI who developed ABI from 16–64 years of age. Further studies should be performed to compare the patient groups by age or the length of time since the occurrence of ABI.

9. This measure has not addressed the changes related to the onset of an ABI – there are too many variables that have not been taken into account Or addressed in this section.

Response: As mentioned in our response to the sixth comment, we considered the LCAS to be able to extract only adaptations associated with ABI. The exact distinction between ABI, aging and other factors may be a subject for a future study. The following has now been added on this point to the revised manuscript (line 300-304):

“The original point is to put forward the new model as opposed to the previous model proposed by Bakas [18,19] with regard to three points: demonstration among not only the family caregivers of stroke patient, but for several types of diseases associated with ABI, focus on the individuals with ABI who developed ABI from 16–64 years of age and carry out recruitment not from hospitals but from the community.”

Editorial Requests:

1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at

https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and

https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf

Response: We appreciate the advice and have now used the PLOS ONE style templates to prepare our revised manuscript.

2. In your Methods section, please provide additional information about the participant recruitment method and the demographic details of your participants. Please ensure you have provided sufficient details to replicate the analyses such as a) the recruitment date range (month and year), b) a description of any inclusion/exclusion criteria that were applied to participant recruitment, c) a table of relevant demographic details, d) a statement as to whether your sample can be considered representative of a larger population, e) a description of how participants were recruited, and f) descriptions of where participants were recruited and where the research took place.

Response: As suggested, we have now added the information requested.

a) Line 144-146

“The survey was conducted among 1622 family caregivers of individuals with ABI who belonged to associations for families in Japan and were selected as eligible participants between September 2019 and November 2020.”

b) Line 150-156

“Of these, 39 associations (47.5%) participated in the study, and a questionnaire was distributed to the family caregivers of individuals with ABI who met the following inclusion criteria: 1) caring for an individual with ABI, 2) ≥20 years old, 3) a family member of an individual with ABI, and 4) the individual with ABI developed ABI at 16–64 years old. The following exclusion criteria also had to be met: 1) not caring for an individual with ABI, 2) ≤19 years old, 3) not a family member of individual with ABI, 4) the individual with ABI developed ABI at <16 or >64 years old.”

c) P.14-16

The relevant demographic and clinical characteristics of this study are shown in Table 1 (p.14-15) and Table 2 (p.15-16). We have now added the number of respondents to each variable.

d) Line 293-299

“Regarding the demographics of the family caregivers of individuals with ABI, the caregivers were mostly women (75.5%). The average age at which the individual with ABI developed ABI was 37.2 years (SD = 14.3). According to the official evaluation by the Japanese government and a previous study, this is nearly identical to the profile of participants in the survey on the family caregivers of individuals with ABI [17]. Thus, the sample was deemed representative of the population of family caregivers of individuals with ABI.”

e) and f) Line 146-148

“The 82 associations were selected from a list that is publicly available in Japan. The author sent informed consent letters and questionnaires to the administrators of each association. Each participant was asked to complete the voluntary self-administered anonymous questionnaire by the staff of each association.”

Submitted filename: Response to Reviewers.docx

Click here for additional data file.

23 Sep 2020

PONE-D-20-15809R1

Development of the life change adaptation scale for family caregivers of individuals with acquired brain injury

PLOS ONE

Dear Dr. Shindo,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Reviewer's have suggested some minor revision to the manuscript before final acceptance. Please address Reviewer 1 modifications in the attached file and Reviewer 2 commentaries included at the end of this letter.

Please submit your revised manuscript by Nov 07 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Manuel Fernández-Alcántara, Ph.D.

Academic Editor

PLOS ONE

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: I Don't Know

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: There are a few remaining copy edits that would make the document stronger throughout--very minor edits.

Reviewer #2: The authors have addressed the reviewers previous comments. This paper is reading well. There are a few minor revisions needed:

1. Please re-write the sentences on lines 146-152 so that the procedure is clearer to the reader.

2. Table 1 – Change ‘relationship to ABI’ to ‘relationship to individual with ABI’ (so that the terminology is consistent with Table 2.

3. Table 3 is still not legible. Please amend.

4. Table 5 – align the factors to the left of the column

5. The discussion needs to address issues related to the majority of family members are aged 55-74 years and length of time since injury – and how this impacted on the findings regarding adaptation. This does impact on life issues that are impacting on the family. For instance, families who have parents in this age range are more likely to have adult children who are no longer dependent. This is likely to therefore impact on the adaptation of the family to the circumstances they face in relation to ABI.

6. Limitations also need to be included

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Kim A. Gorgens, Ph.D., ABPP

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Submitted filename: PONE Review 2.docx

Click here for additional data file.

8 Oct 2020

Thank you very much for your e-mail regarding our manuscript, “Development of the life change adaptation scale for family caregivers of individuals with acquired brain injury” (PONE -D-20-15809). We are grateful to know that it is potentially acceptable for publication in PLOS ONE. Please find attached a revised version of our manuscript.

Your comments and those of the reviewers were highly insightful and enabled us to greatly improve the quality of our manuscript. We include below our point-by-point responses to each of the comments of the reviewers as well as your own comments.

We look forward to hearing from you regarding our re-submission. We would be happy to respond to any further questions and comments that you may have.

Response to Reviewers

To the comments of Reviewer #1

1. Line 65 should read “these individuals can achieve.” On the same line through 66 it is unclear what “this measure” is referring to.

Response: “This measure” refers to measuring the life change adaptations. We have revised the text as follows (line 63-65 and line 66-67):

Line 63-65

“However, the family caregivers of individuals with ABI can experience not only negative adaptations to life changes but also positive adaptations following the onset of ABI, and such positive life change adaptations are just one of the benefits these individuals can achieve.”

Line 66-67

“Measuring the life change adaptations makes it possible to evaluate family caregivers of individuals with ABI and the health services offered by health professionals.”

2. On line 122 PsychInfo is improperly referred to as “Psycho-Info”.

Response: We have written it according to the American Psychological Association (https://www.apa.org/pubs/databases/psycinfo/) (line 122-123).

3. Line 130 is missing a period after “22 items”.

Response: We have added a period after “22 items” (line 130).

4. Line 240 could benefit from copy editing (“The percentage of at least either one of response is higher than 85% of the sample.)

Response: We have corrected the text as follows (line 248):

Line 248

“Item with a score (-3 to +3) of 85% or higher in the sample.”

5. The clarification of how middle-age and older-age differ in developmental tasks in lines 81-84 does serve to improve understanding of the life course and roles of the family caregiver. Additionally, on line 77 older age is defined as above 65 years. Adult age is defined on line 78 as 16-44 years. Adding an age range for middle-age individuals is suggested here on line 79.

Response: We considered ‘middle-aged’ to be 45-64 years old. We have now added the age range for middle-aged individuals as follows (line 78-81):

Line 78-81

“While the family caregivers of individuals with stroke are often in older age rather than middle-aged individuals (45-64years) [22], the family caregivers of individuals with ABI are often middle-aged or older.”

6. Before publication, it may be useful to describe the reason for including the K6 in more detail. Line 171-172 describes its use to validate the LCAS scale, however the K6 only assesses clinically significant serious mental illness. Therefore, an additional explanation of how this validates the LCAS, which includes positive aspects of mental health and the caregiving experience, seems necessary. Line 272 does state that these results are negatively correlated, but again could use clarification earlier. Additionally, the K6 in the English language version is scored from 1-5 where in line 173 the authors state, “each question is scored from 0 to 4”. The 4 point scale anchors described in the text (1 = completely important, 2 = slightly important, 3 = slightly unimportant, 4 =not important at all) are not the same as appear on the English-language version of the instrument (a 7 point scale from “The most deterioration” to “did not change” to “The most improved”) which is a substantially different instrument than the one described.

Response: The K6 assesses clinically significant serious mental illness using the optimal cut-off point, as the reviewer suggested. In addition, a previous study considered the K6 to assess the mental health using a continuous scale, with higher scores reflecting a poorer mental health (Oshio and Kan, 2016). Another previous study further cited a correlation between caregivers’ mental health and the perception of life changes (Negarandeh et al., 2015). Based on the findings from previous studies, we hypothesized that mental health deterioration in cases with higher K6 scores reflected negative life change adaptation with lower LCAS scores. We have now clarified how the K6 validates the LCAS (line 178-184) and corrected the explanation concerning validity in the text (line 280-282). In addition, we apologize for the confusion concerning the 4-point scale for the K6. We used the Japanese version of the K6 developed by Furukawa et al. [35], which is scored from 0-4. We have now added explanations about the 4-point scale for the K6 (line 172-174).

Line 172-174

“Each question rated the frequency of distress symptoms. The responses were scored as follows: 0 = none of the time, 1 = a little of the time, 2 = some of the time, 3 = a lot of the time, 4 = all of the time; thus, the total score ranges from 0 to 24.”

Line 178-184

“A previous study considered the K6 to be a continuous scale in which higher scores reflect lower levels of mental health [36]. In addition, another study explained that there was a correlation between an adverse impact on caregivers’ mental health and the negative perception regarding life changes [5]. Based on the findings from previous studies, we predicted that mental health deterioration in cases with higher K6 scores reflected negative life change adaptation with lower LCAS scores. Thus, the author used this scale as an indicator of concurrent validity.”

Line 280-282

“A negative life change adaptation as well as a low LCAS score showed a significant amount of variance between mental health deterioration as well as a high K6 score (r=-0.50; P<0.001).”

To the comments of Reviewer #2

1. Please re-write the sentences on lines 146-152 so that the procedure is clearer to the reader.

Response: We have carefully corrected (line 147-151).

Line 147-151

“Before sending the survey questionnaires, the author sent informed consent letters to the administrators of all associations of family caregivers of individuals with ABI. Thirty-nine associations (47.5%) consented to participate in the study. The survey questionnaires were distributed to each participant by the staff of each association.”

2. Table 1 – Change ‘relationship to ABI’ to ‘relationship to individual with ABI’ (so that the terminology is consistent with Table 2.

Response: We have changed “relationship to ABI” to “relationship to individual with ABI” (p.14-15, Table 1).

3. Table 3 is still not legible. Please amend.

Response: We apologize for this difficulty and have now enlarged the letters in Table 3 (p.17-18, Table 3)

4. Table 5 – align the factors to the left of the column

Response: We have now corrected this text (p.20-2l, table 5).

5. The discussion needs to address issues related to the majority of family members are aged 55-74 years and length of time since injury – and how this impacted on the findings regarding adaptation. This does impact on life issues that are impacting on the family. For instance, families who have parents in this age range are more likely to have adult children who are no longer dependent. This is likely to therefore impact on the adaptation of the family to the circumstances they face in relation to ABI.

Response: As suggested, we have now discussed how the family members age and length of the time since injury influenced the findings regarding adaptation (line 314-324).

Line 314-322

“The majority of family members being 55-74 years old and the length of time since the injury being over 10 years were considered to have influenced the findings regarding adaptation. In general, families who have parents in this age range are more likely to have adult children who are no longer dependent. The family caregivers of individuals with ABI must fill the role of caring for an adult who is now dependent after having fulfilled their role of caring for their children. The family caregivers of individuals with ABI therefore need to fill a specific role that most family members never experience. This is likely to influence the adaptation of the family to the circumstances they face in relation to ABI.”

6. Limitations also need to be included

Response: We moved the limitations in response to a previous comment from reviewer #1. Therefore, we have added a new subsection for the limitations to the discussion (line 352).

Submitted filename: Response to Reviewers.docx

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14 Oct 2020

Development of the life change adaptation scale for family caregivers of individuals with acquired brain injury

PONE-D-20-15809R2

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19 Oct 2020

PONE-D-20-15809R2

Development of the life change adaptation scale for family caregivers of individuals with acquired brain injury

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