Translation and validation of the caregiving burden scale for family caregivers of children with cancer in chinese population

Caregivers are those who provide extensive assistance to patients with chronic diseases or disabilities and provide the most care during their illness or disability, mainly classified as formal and informal. Formal caregivers are family doctors and trained carers or public service workers who are employed for a fee. The latter refers to relatives who provide free care for the family, including parents, grandparents, maternal grandparents, siblings, friends, or neighbors [1]. Family caregivers of children with cancer are often called as informal caregivers, but it can be extremely challenging for family caregivers who are not specially trained.

To date, the burden of care remains a complex concept with a multidimensional structure. Hoening and Hamilton [2] first put forward the concept of burden and divided it into subjective and objective burdens. Subjective burden relates to the caregiver's feelings about performing the caregiving function, while objective burden is defined as events or activities related to adverse caregiving experiences. Later, Zarit, Reever, and Bach-Peterson described burden as "the degree to which caregivers perceive the emotional, physical, social, and economic status of their relatives" [3]. Collins et al. also proposed that caregiver burden refers to other negative outcomes, such as psychological distress, physical health problems, economic and social stress, damaged family relationships, and feelings of hopelessness [4]. This study is based on the research of scholars at home and abroad on the concept of "caregiver burden" and finally adopts the concept definition proposed by Liu et al. [5] in 2020, that is, caregiver burden refers to the multifaceted pressure level endured by caregivers due to long-term care of family members, and such pressure level will lead to anxiety, burnout, depression, and other problems for caregivers.

The growing number of children with cancer places a considerable burden on tens of millions of family caregivers. Cancer will not only affect the growth and development of children, physical and mental health, but also affect the everyday life of family caregivers, resulting in the breakdown of regular family order, the relationship between children and siblings is involved, and the relationship between partners deteriorates [6]. Family caregivers are the people who have the most prolonged and intimate contact with their children daily. Children will be keenly aware their parents' the poor physical and mental state and then produce negative emotions, which significantly affects the degree of cooperation and treatment effect of children's clinical treatment. According to The first global report on the burden of childhood cancer published by The Lancet, China has the second highest burden of childhood cancer [7].

Using a reliable and valid scale is an effective method to assess the caregiving burden of family caregivers of children with cancer. Currently, the primary tools used to assess Caregiver Burden for family caregivers of children with cancer include Zarit Caregiver Burden Interview (ZBI) [8], Caregiver Burden Inventory (CBI) [9], Caregiver Burden Scale (CBS) [10], Parent Experience of Child Illness (PECI) [11], Caregiver Burden Scale (with positive entries)(CSI +) [12]. However, most of these tools have a long history of development. They primarily targeted caregivers of patients with chronic diseases such as Alzheimer's, Parkinson's, mental disorders, or inflammatory bowel disease [13‐16] and lacked population specificity. Currently, there is no specific tool to measure the burden of family caregivers of children with cancer, which is not conducive to improving the fundamental understanding of the burden of family caregivers of children with cancer and can not provide targeted solutions and social support.

In 2021, Cevik Ozdemir et al. compiled the CBFSC-CC, which assessed the nursing burden of family caregivers of children with cancer from a multi-dimensional perspective, covering four dimensions of physical, emotional, psychological, socio-cultural and economic burden [17]. Compared with the ZBI, CBI, CBS, PECI, and CSI + scales, the CBFSC-CC contains more specific questions about the burden of family caregivers for children with cancer. The scale has only been tested for psychological characteristics by a Turkish development team [17], and the results show that it is a high-quality measurement tool. Based on the actual situation in China, the introduction of CBFSC-CC can not only provide a specific measurement tool for assessing the caregiver burden of Chinese children with cancer but also provide a valuable reference for further research on related intervention measures. Therefore, this study aims to sinicize CBSFC-CC and evaluate the validity and reliability of the Chinese version of CBSFC-CC.

The number of child cancer survivors is increasing year by year [27], and it is family caregivers who bear the burden of care in their lives. Tens of millions of families will experience or are experiencing the long-term stress caused by cancer [28]. Researchers in the field of pediatric oncology are increasingly conducting research on family caregivers of children with cancer. However, in the earlier research stage of this study, it was found that most domestic and international scholars used the Zarit caregiver burden scale when quantifying the caregiver burden of family caregivers, especially domestic scholars [29‐31]. Therefore, this study introduced CBSFC-CC to assess the nursing burden of family caregivers of children with cancer, providing a specific measurement tool for future clinical studies on family caregivers of children with cancer in China.

In this study, the results of the item analysis manifested that all but two items (item three and four) had adequate discriminability for inclusion in this measuring tool. The structural validity of the Chinese version of CBSFC-CC was verified. Structural validity is used to test the degree to which the structure of scale items corresponds to its theoretical concept [32]. Five common factors were extracted for the first time in the exploratory factor analysis results, and the cumulative variance interpretation rate was 63.24%. Due to the phenomenon of dimensional rubbing and double loading in items 14, 19, 21, 22, 29, 30, 35, and 37, we deleted the above eight items based on the psychological measurement characteristics. After removing these items, we reanalyzed the remaining data and extracted the common factors once more. Then five common factors, with a cumulative variance interpretation rate of 65.80%, were extracted, and the dimension rubbing and double loading no longer appeared. In addition, items 14 and 30 are similar in content to retained item 6, both of which aim to assess caregiver fatigue, so they were deleted. Moreover, the deletion of the above items may be closely related to Chinese culture. Compared to Western countries, Chinese culture puts more emphasis on "familism", usually "family-centered decision-making mode". This emphasizes the responsibility of parents in the family [33]. When children are in need, they feel that it is natural for them to be the primary caregivers and will not easily express their negative inner activities to children and the outside world. Instead, they pretend to be in the best possible position to meet the challenge, making items 19, 21, 22, 29, and 35 difficult to measure. At the same time, for Chinese parents, their time is basically taken up by work and family, and few of them care about their spiritual values. For the family of a child with cancer, it is even more difficult to ask the caregiver to pay attention to spiritual life and participate in relevant practical activities. This is because they need to spend more time earning money for the child's medical treatment [34]. On the other hand, it may also be related to the sex ratio and education level of the sample. It has been found that the higher the level of education, the higher the level of self-care, and more likely to pay attention to spiritual needs, and the self-care ability of women may be lower than men [35, 36]. In the sample of this study, however,more than 80% were women, and less than 20% of the sample had a bachelor's degree or higher. Therefore, item 37 is not applicable to family caregivers of children with cancer in China. At the same time, the gravel chart of factor structure was generated. The first four common factors had the largest slope decline in the scree plot. They contributed more to the principal component analysis than the following common factors, indicating that extracting and integrating into four common factors was more reasonable. Therefore, after sorting out the entries of each factor, it was found that the rotation load of common factor 3 (items 10, 13, 17, 18, 20) and 5 (items 11, 12, 15, 16) was similar, and contained all the entries in the dimension of "emotional burden" in the original scale. Based on the entry content and clinical practice [37], it was considered that there was no need to rename the two common factors and can combine them into a common factor. The items contained in other common factors are consistent with the dimensions of the original scale.

In order to further confirm the rationality of this dimension division, this study conducted an in-depth analysis of the dimensions of the scale and the distribution of items contained in it. The results showed that, except for item 4, the other items were statistically significant (P < 0.01). According to David, the correlation coefficient method shows that the other items' correlation coefficients are 0.33 ~ 0.83, except for items 3 and 4, reaching a good level or above [37]. To sum up, entries 3 and 4 are considered poor quality and cannot distinguish the caring burden of family caregivers, so they can be deleted, which is consistent with the original scale [17].

In the confirmatory factor analysis, most studies believed that χ2/df ≤ 3, CFI > 0.90, TLI > 0.90, IFI > 0.90, RMSEA < 0.08, and SRMR < 0.08, and the fitting results were good [26], but the critical value has been controversial. The fitting effect will be affected by scale dimension, number of items [38], sample size [39]and other factors. The suggested threshold value is only a reference but not a standard. In this study, the model was modified according to the modification suggestions [40]. Furthermore, paths with residuals of 24 and 25, 37, and 38 were added. However, the modified results could have been better, and the fitting index did not meet the requirements. This situation was discussed with statistical experts. After analysis, statistical experts believed that the overall scale and each dimension had high internal consistency and good stability, which might be affected by scale items and sample size, so this model could be accepted [37]. Adam et al. [40] also believed that when conducting exploratory factor analysis, the limitations of model modification should be acknowledged, and data results should not be excessively relied on. It does not make sense to keep changing the data or adding paths to achieve an ideal fit metric.

Cronbach 's α was used for testing the reliability of the Chinese version of CBSFC-CC. The Cronbach 's α of all dimensions of the Chinese version CBSFC-CC is > 0.8, the half-way reliability coefficient is > 0.8, and the retest reliability coefficient is > 0.9. The Cronbach's α and the retest reliability coefficient of the whole scale are even higher than the original scale [17], and the recommended coefficient at 0.7 [20], indicating that the Chinese version of CBSFC-CC has good reliability and stability, which is consistent with the results of the original study.

Based on the Beaton cross-cultural debugging guide, this study introduced the nursing burden scale for family caregivers of children with cancer abroad. On the basis data of family caregivers of children with cancer in China, the Chinese version of CBFSC-CC was finally formed, including four dimensions (see Appendix). They were physical burden (7 items), emotional burden (9 items), psychological burden (6 items), and social cultural and economic burden (7 items), with a total of 29 items, respectively. It has been verified that the Chinese version of CBFSC-CC has high quality, good reliability and validity, and can effectively measure the level of nursing burden of family caregivers of children with cancer in the context of China.