Foot Care Knowledge and Practices among Japanese Nurses and Care Workers in In-home Service Providers: A Cross-Sectional Study

Background: Aging increases the likelihood for developing foot problems and reduces an individual’s ability for foot care. Hence, foot care knowledge and practices among nurses and care workers in the community greatly impact foot health maintenance and prevention of foot-related problems among older people. This study aimed to explore and examine the current foot care knowledge, practices, and perceptions among nurses and care workers in in-home service providers, along with their demographic characteristics and daily number of clients. Methods: This study analyzed 232 randomly selected front-line nurses and care workers across 35 in-home service providers in N City, A Prefecture, Japan. Data were obtained using questionnaires and subsequently analyzed using descriptive statistics, t-tests, Chi-square tests, Wilcoxon rank-sum tests, and Spearman’s rank correlation tests. Results: Among the 305 providers surveyed, 232 (76.1%; 63 nurses; 170 care workers) provided data. Although 57 nurses (91.9%) and 142 care workers (83.5%) showed interest in foot care, 33 nurses (53.2%) and 133 care workers (78.2%) stated that foot care education was insufficient. Knowledge and practice scores were associated with working status. Significant differences in items related to early detection of foot problems (34.2%) and skin tears on lower limbs (25.5%) were observed between nurses and care workers. Both groups had low accuracy rates in the Shoes and Socks subscale. For practice, both nurses and care workers had low mean scores for checking client’s shoes (2.0/5.0 and 2.1/5.0, respectively), method for reducing ingrown nail pain (2.6/5.0 and 1.9/5.0, respectively), and opportunity for discussing foot care with others (2.7/5.0 and 2.2/5.0, respectively). A significant correlation between knowledge and practice scores was observed among nurses (0.331, p < 0.05) and care workers (0.339, p < 0.001). Conclusions: Despite the presence of several barriers toward enhanced care delivery to


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greater opportunities for nursing care at home, at day care service centers, or at day care centers offering rehabilitation [14]. Japan has two insurance programs that allow older people access to medical or nursing care (Appendix 1) according to their condition (i.e., some are vulnerable and bedridden, while others have good health). After matching procedural demand and supply, older people subsequently receive the necessary medical or physical care, as well as assistance with activities of daily living, from nurses and care workers providing home care services. Both nurses and care workers have equally high opportunities for physically contact with older individuals. Moreover, care workers' subjective observation regarding the client's physical and emotional condition are often shared with nurses and care managers in Japan. Previous studies in other countries have investigated nursing assistants' detection of early signs of infection or acute or chronic illness in nursing homes [15][16][17][18]. Thus, both nurses and care workers function autonomously in detecting foot problems, making decisions regarding foot care, and reporting to other health care professionals. Foot problems have been widely studied internationally. However, literature regarding foot conditions and foot care has predominantly focused on diabetes [19], while limited studies have been available on foot care knowledge, practices, and perceptions among nurses and care workers in home or community settings. Considering that podiatry is not considered as a specialty in Japan, foot care knowledge and skills can be obtained at private schools that charge exorbitant tuition fees. Moreover, the lack of foot care education within academic curriculum may lead to insufficient foot care knowledge and practices among nurses and care workers. The present study aimed to explore and examine the current knowledge, practices, and perceptions among nurses and care workers in in-home service providers, along with their demographic characteristics and daily number of clients. This survey can serve as a reference for the future development of more effective foot care 5 tools for nurses and care workers in home or community settings. The present study hypothesizes the following: 1.
Both nurses and care workers show interest in learning foot care but may perceive to have insufficient education on and time for foot care and display a lack of confidence in the same.

2.
No significant differences in foot care knowledge and practices exist between nurses and care workers regardless of working status or experiences due to the fundamental lack of foot care education in Japan.

3.
Nurses obtain and demonstrate better foot care knowledge and practices related to vascular, neurologic, and skin disorders compared to care workers due to differences in educational curriculum.

Research design
This was a cross-sectional study using random cluster sampling. Target participants comprised nurses and care workers from 35 different in-home service providers [14] in N city, A prefecture, Japan. Data were collected from July to August 2019.

Instruments
Data were collected via questionnaires called Kashiko XJP, which were developed specifically for nurses and care workers included in this study. The questionnaires consisted of the following: (1) questions on demographic characteristics, daily number of clients or number of clients with foot problems, and perceptions regarding foot care; (2) 30 questions on foot care knowledge; and (3) 20 questions on foot care practices.

Sampling and Participants
Currently, 5381 nurses and 23,830 care workers work at in-home service providers in A Prefecture [20]. This study targeted nurses and care workers working at centers providing home care, home nursing, day care services, or day care services with rehabilitation.
Registered nurses (RN), licensed practical nurses (LPN), certified care workers, and noncertified care workers with different types of qualifications were included. Other countries identify care workers as "nursing assistants" nursing aides [15,18]. The sample size was calculated based on a 95% confidence interval and 5% margin of error using a sample size chart. Accordingly, an initial sample size of 530 nurses and care workers was targeted with a nurse/care worker ratio of 20%/80% (1:4) and a 10% participant rejection rate. The inclusion criteria were nurses and care workers who (1) worked part-time or full time, (2) provided physical care, including but not limited to walking assistance, diaper changing, bathing assistance, exercise promotion, and oral care assistance, and (3) worked for centers that never participated in any other foot care programs besides the current study. The questionnaires used herein were developed in Japan and were initially based on foot care knowledge and practice questionnaires for nurses in Finland [11,19]. However, given the inclusion of care workers in the present study and the geographical differences in the standards of care between Japan and Finland, modifications to these questionnaires were required in order to address the purpose of this study. Therefore, a new questionnaire was developed utilizing three phases.
Phase one: draft creation The item pool ( [Insert Table 2 here] Phase 2: Content validity Four experts, including a nurse researcher, a previously contacted foot care specialist (IY), and two researchers specializing in toe movement, as well as two nurses and a care worker with field experience, were contacted to review the draft questionnaires and provide their opinion regarding the usability and necessary adjustments at this stage. The validity of draft questionnaires was evaluated using two processes. Firstly, questionnaires were mailed to eight experts and hand-delivered to one expert for evaluation using the Content Validity Index (CVI), an internationally recognized scale and the most widely used approach for assessing content validity [22]. These experts included a foot care specialist (n = 1), nurses with extensive foot care experience (n = 3), a nursing academic researcher (n = 1), physical therapists specializing in foot and toe therapy (n = 2), a surgeon with extensive knowledge on foot physiology (n = 1), and a doctor with extensive knowledge on wound care (n = 1

Data analysis
Data were recorded by two separate teams working simultaneously with the same information without being observed by the researchers using an outsourcing company.
Data were then categorized into two groups, nurses and care workers, and subsequently analyzed using SPSS 24. Descriptive statistics, χ 2 tests, and the Wilcoxon rank-sum test were utilized for data analysis. Content validity was analyzed using the ceiling effect with means ± standard deviations, while reliability was analyzed by calculating Cronbach's alpha values. Spearman's rank correlation was used to determine the correlation (1) between knowledge and practice scores and gender, working experience in the current profession, and number of clients cared for per day and (2) between knowledge scores and practice scores. The association between age and working status and knowledge and practice scores was analyzed using Student's t-test.

Results
Demographic characteristics, daily number of clients, and perceptions on foot care Among the 232 respondents, (52 RNs, 10 LPNs, 98 certified care workers, and 72 noncertified care workers with different types of qualifications), 225 were ultimately analyzed after excluding two nurses and five care workers for non-response to questions ( Figure 1).
Effect size was calculated using EZR for both knowledge and practice: Formula = (mean scores for nurses − mean scores for care workers) / [(SD for nurses + SD for care workers) / 2].The number of nurses and care workers used in the formula included those who answered all questions. Although an effect size of 0.6 was calculated, a statistical power of 0.95 was obtained. Therefore, the final number of participants (225) was acceptable despite the initial target being 530.
The ratio between nurses and care workers was 1:3, which was quite close to the initially targeted ratio of 1:4. Complete results for demographic characteristics, daily number of clients, and perceptions regarding foot care are presented in Tables 3 and 4.
Nurses and care workers had a mean age of 51.2 (SD 12.2) and 47.8 (SD 11.6) years, respectively. Nurses and care workers provided care to a mean of 7.9 (SD 8.3) and 9.5 (SD 11.6) clients with foot problems in the last month, respectively ( [Insert Table 3 here] [Insert Table 4 here] 11 Around half of all nurses (29,46 As shown in Table 5, practice scores were significantly associated with work status (part time and full time) for both nurses and care workers. Mean practice scores were higher among full-time providers than part-time providers in both groups.
[Insert Table 5 here] Mean practice scores were found to be associated with the number of clients cared for per day among nurses and working experience in the current profession among care workers.

Foot care knowledge
Among the 232 participants included, 225 (96%) completely answered all questions regarding knowledge, while 7 (4%) did not answer parts of the questions. Table 6 details the accuracy rates of the answers. Significant differences were observed in the early detection of foot problems (Vascular and Neurologic 21) and skin tear on lower limbs (Skin 5) between nurses and care workers, with an accuracy difference of 34.3% and 25.5%, respectively, which was highest among knowledge items. Accuracy rates in both groups were low for the Shoes and Socks subscale.
[Insert Table 6 here] Foot care practices Result for questions regarding practices among nurses and care workers are presented in [Insert Table 7 here] Nurses and care workers had low mean scores for checking clients' shoes (2.0 and 2.1, respectively), method for reducing ingrown nail pain (2.6 and 1.9, respectively), and talking about foot care with other staff members (2.7 and 2.2, respectively). However, nurses and care workers had relatively high means scores for skin moisturizing (4.2 and 3.9, respectively) and bathing effects (4.0 and 3.6, respectively).
Although a ceiling effect was observed for items Nail 3, Skin 3, and Hygiene 2, they were statistically acceptable given their SD of 1.4, 1.1, and 1.1, respectively (Table 8).
[Insert Table 8 here] Results for Cronbach's alpha are detailed in Table 9. Accordingly, items on Skin [Insert Table 9 here] Correlation between knowledge and practice scores The correlation between knowledge and practice scores is presented in Table 10.
Accordingly, a significant correlation between overall knowledge and practice scores was observed among both nurses (0.331; p = 0.017) and care workers (0.339; p = 0.000).
Spearman's rank correlation test showed that the association between knowledge scores and Movement and Toe Exercises was above 0.4 for nurses, while association between knowledge scores and Skin, Hygiene, and Movement and Toe Exercise were above 0.3 for care workers.

Discussion
The results of the present study showed a significant association between foot care knowledge and practices among both nurses and care workers. The purpose of this study was to explore the strengths and weaknesses of both professions with regard to the provision of foot care and to develop strategies that improve the level of care within this area. One of features of the present study was the inclusion of care workers among the study participants. Care workers working in in-home service providers have countless opportunities to assess and come in contact with the client. Thus, statements like "he/she is not as usual" by non-nurses should be taken seriously and require follow-up [15].
Our results showed that both nurses and care workers were interested in learning about foot care and observing clients' foot problems despite having low confidence, insufficient time, and limited foot care education. Indeed, 57 (92%) nurses and 165 (97%) care 14 workers had cared for a mean of 7.9 and 9.5 clients with foot problems a month before the survey.
In contrast to our hypothesis, a significant correlation between working experience and practice scores had been observed, with full-time participants having higher mean scores.
Moreover, working experience was significantly associated with practice scores among care workers. This is consistent with results presented in previous studies [19].and could perrhaps be attributed to increased chances for foot care practice with greater working hours.
Higher accuracy differences in the early detection of foot problems had been observed between both groups in contrast to our hypothesis. Despite nurses having received more in-depth anatomy and physiology education compared to care workers, only slight differences had been expected given the lack of foot care education in both professions.
Previous studies indicated nursing assistant' detection of early signs of symptom contribute to health care [15,17]. Older people with low risk of foot problems might be undiagnosed and overlooked; therefore, they need medical help [23] and with high risk may develop worse conditions [24,25].
Early detection and reporting of foot problems by care workers may lead to early treatment, which could potentially be life-saving. Therefore, enhancing knowledge on early detection among care workers should be emphasized.
The present study found that knowledge on shoes and socks had been lacking among both professions given the lower accuracy rates of related answers. Despite having more opportunities to observe the client's foot when assisting with the wearing of shoes and socks or bathing, care workers were less aware of foot arches compared to nurses.
Inappropriate shoes can cause calluses or corns, as well as toe and arch deformity [26,27]. This is significant considering that the arch of the foot plays a vital role in balancing 15 or walking. Although the effect of inappropriate footwear on the structure of foot has been extensively studied in other countries [27][28][29][30][31][32], limited research on the same has been available in Japan.
Nurse and care workers were aware of the protective effects of moisturizers on the skin barrier; however, the 25.5% knowledge difference between both groups regarding skin tears should be emphasized in future foot education programs. Considering the decreased elasticity, dryness, and fragility of older people' skin, identifying factors that trigger skin tears on their arms and feet can prevent further skin problems. Accordingly, Serra R et al.
had reported risk factors for skin tears among frail populations [33]. Notably, small stones or objects inside the shoes may lead to skin breakage on the foot. Observing for signs on skin from improper footwear is imperative [34] Assessment of the skin between the toes and on the heel has also been poor among Japanese studies, unlike those in other countries [35][36][37]. Skin maceration between the toes may increase the risk for developing cellulitis from fungal infections. Indeed, a hospital based-study in Japan reported fungal infections among older people individuals [38], with another study on older people living at home and in nursing homes also showing the same [39]. Hence, assessing the skin between the toes should be included in a health care provider's daily routine.
The present study found that more nurses than care workers practiced nail care. However, nurses had the lowest scores for ingrown nail care among the items on nail care practice.
Admittedly, foot nail care, particularly nail cutting, among older people individuals can be challenging for both of nurses and care workers. Changes in nail characteristics may be normal and related to the natural aging process. However, nail disorders, including thickened, elongated, and ingrown nails, can be painful and disabling [40]. The MHLW in Japan provided a guideline to inform nurses and care workers on foot care based on qualifications [41]. Such information would be beneficial for the safe and regulated 16 practice of foot care among nurses and care workers. Learning to use a grinder and toenail clipper requires time and knowledge. Care providers may also learn to use a nail file for reducing nail thickness to some degree or shape the nail edge. Nail disorder not only caused cosmetic problems but also showed negative effects on health related quality of life and psychological problems [13,42] studies can also be used as reference [35,47,48].
Secondly, the lack of foot care education in the school curriculum as well as in the work field has hindered foot care practice in Japan. According to one study, 78.7% (48) of nurses and 75.7% of care workers (128) stated that foot care manuals are necessary.
Moreover, the results presented herein showed that foot care knowledge came from various sources, with some care providers not even knowing the source (Table 3). Hence, a certain structured system for foot care education should be incorporated into the current academic curriculum. Detecting foot problems or providing foot care for particular foot problems among older people individuals has remained challenging. Stolt et al.
stressed the necessity of having regular, organized continuing education for all professional nurses engaged in clinical practice [11].
Gaining knowledge and practical experience through education or training sessions has been shown to foster confidence. Lack of confidence may affect the delivery of care [49].
Self-efficacy and confidence has often been associated with self-care behavior among patients with diabetes [50]. Nurse and care worker confidence may supplement foot selfcare insufficiency among older people due to aging. Coping with nail thickness or reducing edema, however, may require further foot care education and training.
Thirdly, the lack of foot care specialists has hindered appropriate treatment of foot problems in Japan. Accordingly, Japan does not provide a national license for foot care specialists or foot care doctors equivalent to a podiatrist or pomologist. Moreover, the present study suggested that the current consultation system is lacking due to an absence of podiatry referral system in Japan compared to other countries [51][52][53]. While the incorporation of referral recommendations may be influenced by many factors [53], communication channels represent the strength of an organization. Considering that nurses and care workers in in-home service providers do not immediately receive orders from doctors, unlike those in the hospital, they may have more autonomy over decisions regarding further referral after observing or assessing the foot problem.
The present study has explored the requirements for future foot care programs targeting nurses and care workers. Given the various current limitations, new approaches toward enhancing knowledge and practice among nurses and care workers need to be developed and exercised in the future. Additional large-scale studies on nurses and care workers in in-home service providers will be essential. However, researchers need to formulate strategies that address potential participation bias with the current Japanese working situation.

Study limitations
The participants included herein were collected using cluster sampling. Thus, once a field manager of a service center expressed willingness to respond to this study, nurses and care workers were more likely to cooperate with the study. Nonetheless, we need to accumulate evidence and provide reasons for the achieved response rates. Although 530 participants were initially targeted, this number could not be met due to time and budget constraints. Nonetheless, the final sample size was determined to be statistically appropriate. Non-certified care workers had several different types of certificates, the differences in which could not be analyzed due to the small number of participants.
Moreover, some nurses worked as home care providers, which allowed them more time to

Conclusion 19
The present study showed that participants' interest levels and willingness to learn about foot care was inversely proportional to their access to education.
Moreover, areas of early detection of foot problem, skin tear, as well as shoes and socks were identified to be improved. We believe that the results presented herein will aid in the future establishment of intervention programs targeting nurses and care workers in inhome service providers, which would directly and positively impact foot health among older people individuals.

Appendix 1: Japanese Insurance System
Japan has two types of insurance that older people can use to access care. The first insurance type is the National Health Insurance (NHI), which is paid for by all Japanese citizens and residents under 75 years old, although some companies pay for their employees' premiums. Payment of the aforementioned premium grants an NHI card to an individual that covers 70%-90% (typically 70%) of the cost for all eligible treatments. The cardholder will be responsible for the remaining 10%-30% (typically 30%) of the treatment cost. The second insurance type is the Long-Term Care Insurance (LTCI), which is an extra charge paid by all Japanese citizens and residents over 40 and under 75. This type of insurance specifically covers illnesses related to old age or certain health problems for younger individuals. The LTCI can be claimed starting at the age of 65, or 40 for those with specific conditions, and will cover 70%-90% of the cost for eligible treatments. The cardholder will be responsible for the remaining 10%-30% of the treatment cost, with the exact amount paid depending on the cardholder's previous income [54].
Currently, older people individuals receiving community-based care are divided into two groups. The first group consists of individuals who either do not require any home care from community service centers or are receiving family support. This group may consult with doctors at outpatient departments when necessary using their NHI. The second group 20 consists of individuals who require or wish to receive home care from nurses or care workers employed by health service centers, short-stay service centers, or communitybased service centers, such as day care centers. All relevant care is covered by either the LTCI or NHI.
To receive home nursing care services using the LTCI, a request to the relevant government department must be made either in person or by a designated family member. According to current calculations based on statistics from the MHLW as of March 2019, approximately 18% of individuals over 65 are recipients of the LTCI, among whom 57% use the coverage afforded to them under this program [55,56] The remaining 82% of the population aged 65 years and older may have been denied care due to a non-qualifying condition or having been categorized into the pre-care group.
Some older people and their families may have no knowledge or information regarding the Ethics approval and consent to participate 21 The Ethics Committee of the Human Environments University (2019N-002) and Nagoya University (2019-0150) approved this study. This study was conducting in accordance with the Helsinki Declaration. Information related to the purpose of the study, privacy, the right to discontinue, and future publication has been included in the cover letter. Written consent for study participation was implied by the submission of a completed questionnaire.

Consent for publication
Not applicable

Availability of data and materials
All data generated or analyzed during this study are included in this published article and its supplementary information files.

Competing interests
The authors declare that they have no competing interests.

Funding
This study was partially funded by grants-in-aid for scientific research (2019-0150) Author contributions KF designed the study and collected, analyzed, and interpreted the data. TK and AM contributed to the concept of the study. TF and MN contributed to the interpretation of the data.  Age, working experience in the current profession, and number of clients for per day 32 were analyzed using "test for no correlation" Sex and working status were analyzed using Student's t-test *p < 0.05, **p < 0.01, *** p < 0.001    Figure 1 Trial profile

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