Introduction
Alzheimer’s disease (AD) is a chronic, progressive brain disorder that significantly impacts memory, intelligence, and self-care abilities. It is characterized by deficits in speech and motor functions, difficulties in recognizing familiar faces or places, and impairments in planning, organization, and abstract reasoning [1].
The diagnosis of Alzheimer’s, or even the mere possibility of developing the disease, often instills a complex mix of emotions, including fear, anxiety, and uncertainty in patients, their relatives, and caregivers [2]. Research indicates that while many may experience panic, others may grapple with confusion, sadness, or stress when confronted with a diagnosis, highlighting the emotional complexity surrounding Alzheimer’s. This condition is increasingly recognized as one of the most concerning disorders in contemporary society, often described as “the endless funeral ceremony“ [3]. Alzheimer’s disease is the leading cause of dementia among the elderly, representing a significant portion of all dementia cases [4]. A majority of individuals with dementia, including those with Alzheimer’s, reside in low- to middle-income countries [5, 6], which often face unique challenges in healthcare delivery. In developed nations, Alzheimer’s ranks as the third leading cause of death, following cardiovascular diseases and cancers [7]. As of 2021, it remains the primary cause of dementia and the fifth leading cause of death globally [8]. Age is the most significant risk factor for developing this disease [9]. Projections indicate that the number of individuals with Alzheimer’s in the United States will rise from 5 million in 2014 to 13.9 million by 2060 [10].
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According to the report of the International Alzheimer’s Association, every 2.3 s a new case is added to the number of patients of this disease, and according to the predictions, this figure will reach one second in 2050. It is expected that the number of Alzheimer’s patients worldwide will reach 65.7 million people by 2030 and 115.4 million people by 2050 [7].In 2019, a systematic study was conducted in Iran, in which the prevalence of Alzheimer’s disease was estimated to be 2.3% among population ages 67 to 87 [11].
Given Iran’s demographic structure, which includes approximately 31 million middle-aged individuals and a significant elderly population expected in the coming decades, it is reasonable to anticipate an increase in the prevalence of Alzheimer’s disease [12, 13].
Family caregivers (defined as relatives providing essential support and care for patients) play a crucial role in both patient well-being and the healthcare system [14]. The dependence of individuals with Alzheimer’s on their caregivers for daily needs underscores the importance of addressing the challenges associated with care [15]. In Iran, the family serves as the primary support system for patients. Consequently, families bear the heavy responsibility of caring for these individuals, often without adequate resources or support. This lack of formal and informal support affects the challenges that face caregivers [16].
While negative aspects of caregiving are often emphasized, it is essential to recognize that caregiving can also lead to positive emotions and outcomes. Many family caregivers operate without sufficient information or external support, even amid increased service availability; typically, they seek help only during crises [17]. Formal assistance, such as professional home care services, counseling, or support groups, can alleviate some burdens, yet many caregivers sacrifice personal time and face financial strains as a result of their caregiving roles [14].
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The COVID-19 pandemic has further intensified the challenges faced by family caregivers of individuals with Alzheimer’s disease, increasing feelings of stress and isolation. Research indicates that caregivers have experienced heightened emotional distress due to fears of virus transmission and disruptions in routine care services [18]. This underscores the urgent need to understand the factors influencing caregivers’ ability to continue their roles during such unprecedented times. The current research aims to explore the factors affecting the ability of family caregivers of Alzheimer’s patients to persist in their caregiving roles. A deep understanding of these factors necessitates qualitative approaches, allowing participants to provide nuanced insights. By utilizing qualitative methods, researchers can identify effective strategies to improve the quality of life for families of Alzheimer’s patients while enhancing care for elderly individuals with the disease.
Materials and methods
This qualitative study was conducted in Babol, a city in northern Iran, which consists of seven districts. Each district was treated as a cluster for sampling, with a particular focus on the central part of the city where therapeutic and medical services are concentrated. The study aimed to identify Alzheimer’s patients in clinics and conduct interviews with their families, specifically targeting caregivers who had provided care for a significant duration, in line with the study’s criteria. In this context, caregivers are typically family members with relevant experience or education. Sampling efforts were informed by demographic data from clinics regarding patients and their caregivers, considering factors such as caregiver gender, education, and duration of care. The research employed conventional content analysis, a well-established method as outlined by Hsieh and Shannon (2005) [19].This approach systematically codes and categorizes textual or visual data to uncover patterns and themes without the influence of preconceived ideas. The process includes data collection, coding key concepts, developing categories, and interpreting findings to derive insights, aiming for a comprehensive understanding of the content. In total, the study involved 22 participants and effectively applied this method to identify patterns and themes, facilitating a detailed understanding of individuals’ experiences and perceptions. Conventional content analysis is widely used across various fields, including social sciences, media studies, and health research, allowing themes to naturally emerge from the data without imposing prior assumptions.
Sampling and recruitment
Family caregivers were selected through a purposeful approach. To collect information, the researchers visited the participants’ homes or workplaces. An effort was made to ensure maximum diversity in social and demographic status, as well as considering the various stages of Alzheimer’s disease after the onset of symptoms.
The location of the interviews was chosen in coordination with the participants. Before the interviews, the research objectives were explained, and participants were assured that their information would be kept confidential and used solely for research purposes. Participants were also informed that they could discontinue the interview at any time without any repercussions.
Inclusion and exclusion criteria
Inclusion criteria consisted of caregivers who had been the primary caregiver for Alzheimer’s patients for at least one year, whose patients had a diagnosis of Alzheimer’s disease confirmed by an attending physician, who signed a written consent form, and who were willing to participate in the study.
Participants must be at least 18 years old to be considered adults. Caregivers are those who care for their family members. Only individuals under 18 years old were excluded from the study. Caregivers could either live with the person they were caring for or provide care remotely. There were no specific limitations in the criteria for selecting participants, such as type of relationship, or living situation.
Data collection and analysis
Data were collected from family caregivers of Alzheimer’s patients through semi-structured, in-depth individual interviews. The interviewer made every effort to create a suitable environment for the interviews. Due to concerns from some families about the coronavirus, some interviews were conducted by phone, and the interviews were not recorded directly; instead, the researchers relied on their notes [20].
The opening questions of the interview were, “Why do you take care of the patient yourself despite the difficulties? Why don’t you give up taking care of them? Why didn’t you send the patient to the nursing home? Why don’t you use a nurse as the primary caregiver at home?”
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At the end of the interview, participants were invited to share any additional thoughts or topics they felt had not been addressed.
The duration of each interview varied from 40 to 83 min, depending on the interviewee’s desire, personal and family characteristics, and their patient care conditions. In addition, the contact information was exchanged between the researcher and the participants, so if they wanted to provide more detailed information or if the researcher faced any ambiguity, the parties could contact each other at another time. After 17 interviews with family caregivers, the data reached saturation because the codes were repeated, and new concepts were not extracted from the interviews. Five more interviews were conducted to ensure data saturation.
This study used Lincoln and Goba standards (Validity, verifiability, transferability, and reliability) to determine data validity [21, 22].
Validity was obtained by continuously observing the data, checking the material from the typed text of the interviews, and holding discussion sessions on the data with the research team. To verify the data, parts of the conversation transcripts, free codes and subcategories have been checked by several experts, and the necessary corrections have been made.
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Data transferability was assessed through purposeful sampling and the selection of diverse participants as well as data-saturated interviews. In order to check the reliability, the research protocol was prepared during the research process, and the data collection process was carefully recorded.
Data analysis was done using Granheim and Landman’s method, which consists of five steps. In the first step, the interviews were immediately written down after conducting each interview. In the second step, the entire text of the interview was reviewed several times for a general understanding of its content. In the third step, semantic units and primary codes were determined.
In the fourth step, based on semantic differences and similarities, compact semantic units were classified into more comprehensive categories. Finally, in the final step, the main topic hidden in the data was extracted [23]. An example of qualitative analysis is shown in Table 1.
This study used the MAXQADA version 10 software to manage and analyze the interviews [24]. The present study has been approved by the Ethics Committee of Mashhad University of Medical Sciences with the code of ethics IR.MUMS.REC.1400.019 and taking into account the Helsinki Declaration in all stages of the study.
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Table 1
An example of qualitative analysis
Main Category | Category | Sub-category | Code | Condensed meaning unit | Meaning unit |
|---|---|---|---|---|---|
On the Fence of the Caring Role | Commitment to care | Being determined | Staying true to your word | Keeping the promise that they made earlier to take care of their patient | “…When my father was dying, I promised him that I would be the man of the house in his stead and that I would take care of my mother. I don’t want to break my promise now.” |
Maintaining stability in challenging situations | Being capable in critical situations | “…when mom had her surgery, everyone lost their cool, and they didn’t know how to take care of mom considering her restlessness. I didn’t wait for mom to get more agitated. I took 100% responsibility for taking care of my mom, although it was difficult.” | |||
Having self-confidence | Trusting their care capabilities | “…come hell or high water, I know that I will never leave my husband. Until now, I have been able to take care of him; I can keep doing it from now on too.” | |||
Being indebted | Being grateful to the patient | Caring for the patient in gratitude for their past efforts | “…I must be very ungrateful to take my mother to the nursing home now that she needs my help.” | ||
Being indebted to the patient | Being faithful to their religion by taking care of the patient | “… a few years ago, my father sold his house so that I could start a business for myself; how can I not take care of him now that he needs me?” | |||
Feeling dutiful | Thinking it is their duty (as a wife, child and…) | Thinking it is their duty to take care of the patient | ” …I am her child; I know it is my duty to care for my mother. Yes, it is difficult, but after all, my mother has worked hard for me all these years in the hope that I will be her helper when she gets old” |
Results
This study was conducted with the participation of 22 family caregivers of Alzheimer’s patients, 13 (59.1) participants were women, and 9(40.9) were men. The mean and standard deviation of the age of the participants was 43.22 (± 8.11). The mean and standard deviation of the duration of caregiving was 3.45 (± 1.68) years. 8(36.4) participants were single, 11 (50) were married, and 3 (13.6) were divorced. 9 (40.9) participants had diploma and above, 8 (36.3) had bachelor’s degrees, 3 (13.6) had master’s degrees, and 2 (9.1) had doctorates. 11 (50) participants were housekeepers, 5 (22.7) employees, 4 (18.1%) self-employed, and 2 (9.1%) retired. 15 (68.1%) participants lived with the patient, while 7 (31.8%) did not. 13 people (59.1%) cared for their mother, 6 (27.2%) for their father, 2 (9.1%) for their mother-in-law, and 1 (4.5%) for their husband. Details of the interviewees can be found in Table 2.
Table 2
Demographic characteristics of participants based on basic information
Category | Details | Percentage (%) |
|---|---|---|
Education | Bachelor’s degree | 45% |
Education | Master’s degree | 10% |
Education | ≥ Diploma | 45% |
Gender | Female | 59% |
Gender | Male | 41% |
Marital Status | Married | 55% |
Marital Status | Single | 27% |
Marital Status | Divorced | 18% |
Caregiver Living Situation | Lives with patient | 64% |
Caregiver Living Situation | Does not live with patient | 36% |
Duration of Care (years) | 1 year | 18% |
Duration of Care (years) | 2–3 years | 36% |
Duration of Care (years) | 4–5 years | 36% |
Duration of Care (years) | 6–7 years | 10% |
In response to the main question, “What factors affect the continuity of caregiving for Alzheimer’s patients by family caregivers?” The main class on the fence of the caring role was extracted along with five subclasses of commitment to care, coercion to care, socio-cultural beliefs and concerns, and attachment and love for the patient.
Main category: on the fence of the caring role
First subcategory: commitment to care
In this subcategory, the participants reported that being committed to their caring role prevented them from abandoning it. Responsibility, which was the personality trait of most family caregivers, created such a sense of commitment in them that they still continue to care for the patient with all their heart and without thinking of entrusting their patients to special care centers, despite all the tensions. This sub subcategory contains sub-sub subcategories such as: being determined, being indebted, and feeling dutiful (Table 3). In expressing their experiences, the participants stated:” …I am her child; I know it is my duty to care for my mother. Yes, it is difficult, but after all, my mother has worked hard for me all these years in the hope that I will be her helper when she gets old.” (Participant No. 1 -Duration of care 5 years).
Second subcategory: coercion to care
Most of the family caregivers stated that they are forced to take care of the patient. Having no other option but to take care of the patient due to the limitations they face in terms of financial, human and situational facilities has put them in a tight spot, and they are forced to accept the current reality. From this subcategory, sub-sub subcategories such as: giving in to the caring role due to family requirements and patient care due to financial problems were extracted (Table 3).
“…the only one that is left is me, and I have to take care of my dad.” (Participant No. 10 -Duration of care 4 years)
Third subcategory: socio-cultural beliefs and concerns
In this context, most interviewees stated that they continue in their caring role because of the cultural beliefs and values they were raised with or struggle with.
In this subcategory, the sub-sub subcategories of spiritual and religious tendencies, social stigma, social fears and strong effects of family values were extracted (Table 3).
In the subcategory of spiritual and religious tendencies, most of the family caregivers stated that they have to take care of the patient because of their spiritual orientation. This includes codes such as: being God-fearing, having a guilty conscience caused by not taking care of the patient, believing in karma, being afraid of receiving punishment in the afterlife and paying attention to religious recommendations of being kind to your parents or spouse, respecting the sick and the elderly, considering caregiving as a good deed, and believing that caregiving is ultimately a divine test; which are all the sub-subclasses of spiritual and religious tendencies.
“…I’m very tired. If I didn’t fear God, I would have put my mother in a nursing home, but every time I think about it more seriously, I feel guilty and regret thinking about it again.” (Participant No. 17 -Duration of care 3 years)“…In the verses and hadiths, it has been said that respecting your parents is obligatory, especially in old age and illness. If I am a Muslim, how can I be indifferent to these issues, which have been emphasized in so many ways?” (Participant No. 21 -Duration of care 5 years)
Fourth subcategory: attachment and love for the patient
In this subcategory, the primary caregivers reported that the patient is so dear to them that they cannot give up caring for them despite the difficulties. In this case, sub-sub subcategories of feeling pity and nostalgia for kinship were extracted (Table 3).
“… As soon as he breathes next to me, I breathe a sigh of relief that he is still alive and next to me. If my husband dies, I will miss all these hardships. I can’t forget all the memories we had together and be indifferent to him; life without him doesn’t have any meaning for me. All my memories and happiness have always been with him; I don’t want to regret losing this time later.” (Participant No. 6 -Duration of care 7 years)
Table 3
An overview of the results
Theme | Category | Sub-category | Free codes |
|---|---|---|---|
On the Fence of the Caring Role | Commitment to care | Being determined | • Staying true to your word • Maintaining stability in challenging situations • Having self-confidence |
Being indebted | • Being grateful to the patient • Being indebted to the patient | ||
Feeling dutiful | • Thinking it is their duty (as a wife, child and…) | ||
Coercion to care | Giving in to the caring role due to family requirements | • Being an only child • Being single • Being unemployed • Staying in their father’s house after their divorce • Other family members having physical problems • Other family members are far from the patient’s place of residence | |
Patient care due to financial problems | • Having financial problems that they are unable to hire a nurse • Having financial problems that they are unable entrust the patient to the nursing home | ||
Socio-cultural beliefs and concerns | Spiritual and religious tendencies | • Being God-fearing • Having a guilty conscience caused by not taking care of the patient • Believing in karma • Being afraid of receiving punishment in the afterlife • Paying attention to religious recommendations of being kind to your parents or spouse • Paying attention to religious recommendations of respecting the sick • Paying attention to religious recommendations of respecting the elderly • Considering caregiving as a good deed, and Believing that caregiving is ultimately a divine test | |
Social stigma and social fears | • Being stigmatized • A negative view of nursing homes • Fear of home nurses not keeping secrets about family issues • Fear of being blamed • Being compared to their peers | ||
Strong effects of family values | • Male children are more important • The rationality of sacrificing a daughter, wife or daughter-in-law in the family (female) • The rationality that the caregiver of the husband’s parents should be the bride of the family • The family has more expectations from female caregivers than male caregivers | ||
Attachment and love for the patient | Feeling pity | • Feeling pity and compassion for the patient • Strengthening maternal/paternal feelings in the caregiver • Considering the patient as helpless | |
Feeling nostalgia for kinship | • Keeping their shared memories alive • The patient being dear to the caregiver • The fear of losing their beloved patient • Being attached to the patient • Being dependent on the patient |
Discussion
This study aims to investigate the factors influencing the ability of family caregivers of Alzheimer’s patients within Iranian families to persist in their caregiving roles. The constraints that confine caregivers to their roles contribute to the ongoing nature of caregiving among family members. In the context of culture, family values, and caregiving traditions, it is essential to examine the experiences and perspectives of family caregivers, as the cultural and religious teachings that shape the caregiving environment are closely linked to the broader cultural and religious contexts of society. Therefore, considering these factors in the design of interventions can effectively address the challenges faced by family caregivers, a consideration that should be prioritized by health policymakers.
In the present study, caregivers’ commitment resembles a chain, binding them to their roles despite numerous challenges. This steadfast sense of responsibility aligns with findings from Ahmed Aghajani et al., who identified an extreme sense of duty as a significant contributor to caregiver distress. Their research highlights the emotional burdens faced by caregivers, which resonates with our results, indicating that, despite hardships, caregivers in our study remain focused on their patients’ needs [25].
Furthermore, a study on family caregivers of patients undergoing dialysis—a known chronic condition—revealed that most caregivers in Iran are similarly dedicated to their roles, reinforcing our findings [26]. In our study, several caregivers identified personal circumstances—such as being an only child, single, living at home post-divorce, unemployed, and having distant family members—as key factors influencing their decision to continue caregiving. Many expressed those financial constraints prevented them from affording professional care, such as hiring nurses or placing patients in nursing homes. This concern is echoed in Ashrafzadeh et al.‘s study, where participants reported that the costs associated with care centers, diagnostic services, and home visits from healthcare professionals were prohibitively high [27].
In general, caregiving affects families financially, as caregivers of elderly people with Alzheimer’s often do not have the ability to earn money. However, they need money for treatment, transportation to the hospital and their daily lives, which causes many problems [28]. The non-cooperation of other family members causes the caregiver to face more challenges [27].
Although a primary caregiver of an Alzheimer’s patient can usually manage the care process, caregiving without the cooperation of others will be challenging and even impossible [29]. According to the results of a study conducted in Hong Kong in 2013, family members often placed responsibility on the most convenient member, such as the person who does not have a full-time job, can sacrifice work, the closest person to the patient, or the one who received the most property (inheritance) [30].
It has been seen that in developed countries, there are various types of care services at home and in the community in order to reduce the burden of caregiving for families; on the contrary, in Iran, the responsibility is solely on the family of the patient [29, 31]. However, it can be seen that caregivers who have a higher income and use professional care services may place their elderly relatives in nursing homes, which is in line with the results of the present study [32].
In this study, most of the participants considered cultural beliefs and values as the main reasons for continuing their role as caregivers because some were afraid of being stigmatized by society if they did not take care of the patient. In a qualitative study conducted in Iran in 2012, the fear of others’ judgment was mentioned as one of the subclasses of family stigma, which is in line with the current study [33].
The participants stated that family members expect more care from women caregivers than men; this factor was more evident in most of the female participants, which can be justified considering that the majority of the caregivers were women. A study in Turkey also show that female caregivers are exposed to higher levels of caregiving burden than their male counterparts [34].
A possible reason for this difference could be due to the social perception about the role and gender of women in societies so in some societies women are expected to be the primary caregivers, even though caring for the elderly is the duty of all family members [35]. But it is evident that if there are both girls and boys in a family, girls and women usually assume the role of the primary caregiver, and to fulfill their roles, they are required to sacrifice and even ignore their well-being and health [36].
In Moraes et al.‘s study, family caregivers were generally women who lived with the patient [37]. In the present study, most of the participants (who were housewives) admitted that because they are housewives, others expect them to continue the caregiving role. It has been seen that insufficient health literacy is the main factor of several health inequalities that can affect women’s spiritual health [38]. Also, the negative view of the nursing home and the fear of home nurses not keeping secrets about family issues among the participants caused them not to entrust the responsibility of care to the nursing home or home nurses.
In Boogaard et al.‘s study, the importance of family caregivers’ trust in healthcare professionals in nursing homes is evident, so it was argued that increasing family caregivers’ trust in nursing home staff by improving communication and information exchange may be a suitable basis for providing optimal palliative care in dementia [39].
In this study, most family caregivers stated that due to their spiritual and religious tendencies, they try their best to take care of their patient themselves and bear the hardships caused by caregiving. Most of the caregivers felt guilty for not taking care of the patient. The belief in karma, the fear of the afterlife and the idea that taking care of the patient is a kind of divine test made them continue caring for the patient. Considering the spiritual atmosphere of society, this view is derived from the idea that one should surrender and accept divine providence. It has been seen that there is a constant relationship with God, as well as asking for patience and help from Him, which can ultimately improve the adaptation of caregivers to the challenges of providing care [25].
Their religion, Islam, was also influential. It encourages respecting the patient, parents and spouse and believing that they will be rewarded for their good work of caring for and nursing the patient, in the afterlife. Because Iran is an eastern society with religious beliefs, many recommendations have been given about being kind to your parents in the culture, religion, and the Muslim holy book (the Qur’an). In the Qur’an, seven duties for children regarding their parents have been given: respect, kindness, obedience, politeness, prayer, support, and caring for them in their old age [40]. Additionally, caregivers’ love for their family members significantly motivates their persistence in caregiving. Despite the difficulties, participants expressed deep emotional attachments, feeling pity and compassion for their chronically ill family members. They cherished past memories and feared losing someone dear to them, worrying they might regret not spending more time together in the future. This emotional connection may reflect the nature of Iranian families, which often serve as primary support systems for chronically ill individuals, fostering strong feelings and relationships among family members [41].
The COVID-19 pandemic has significantly affected caregivers’ mental health, exacerbating feelings of stress, anxiety, and isolation. Research by Gonzalez and Bäuerle found that caregivers of individuals with dementia experienced increased levels of psychological distress during the pandemic, largely due to heightened fears of virus transmission and the disruption of usual care routines. This study emphasizes how the pandemic intensified existing challenges faced by caregivers, including social isolation and limited access to support services [42, 43]. Additionally, a study by J. Parmar et al. highlighted that caregivers reported increased emotional strain and challenges in managing caregiving responsibilities due to pandemic-related restrictions. The findings suggest that caregivers felt more overwhelmed as they navigated the complexities of providing care while also worrying about their own health and that of their loved ones [44]. Research indicates that many caregivers experience significant stress and burnout, which can lead to feelings of inadequacy and hopelessness. A study by Schulz and Eden (2016) highlighted that caregivers frequently report high levels of emotional distress, which can be exacerbated by the demands of caring for someone with Alzheimer’s. This emotional burden can contribute to caregivers feeling overwhelmed and doubting their ability to continue providing care [45].
Multiple studies have examined the experiences of caregivers and their challenges, focusing on the theme of “conflict in caregiving.” These studies indicate that many caregivers feel a strong sense of loyalty and responsibility toward those they care for, while also facing challenges such as financial pressures and social expectations. This conflict creates a sense of “being in a fence” for caregivers, which is also mentioned in our Result [46, 47].
According to a study conducted in Iran, the death of an elderly parent is one of the concerns of family caregivers. Despite the hardships of caregiving, they worry about the loss of their beloved patient and continue to care for them [25].
Strengths and limitations
In this study, in the interview with several participants, there were difficulties at home due to the concern of families about contracting the coronavirus and its transmission to a patient with Alzheimer’s disease, which affected the conditions of the study. An attempt was made to reduce this problem by providing safe conditions for interviews and providing personal protective equipment.
Threats such as researcher bias or inadequate representation of participants could potentially affect the research standards.
To address threats such as researcher bias or inadequate representation of participants, diverse sampling, and researcher training were utilized.
Most of the family caregivers in the study population were women, even though many attempts were made to include gender diversity in the interviewees. The study’s strength was to discover the reasons for the continuation of caregiving for Alzheimer’s patients among family caregivers.
Conclusion
The constraints that keep family caregivers in their roles can make it difficult for them to continue providing care. It is important to consider the cultural values and traditions surrounding caregiving, as these deeply influence the experiences and perspectives of caregivers. Understanding these cultural and religious contexts can inform the design of effective interventions to address the challenges faced by family caregivers.
Additionally, the studies reviewed highlight how the pandemic has increased caregiver stress and emphasized the urgent need for ongoing support and resources. To better support caregivers, policymakers and healthcare providers should prioritize their well-being by ensuring access to essential resources, respite care, and mental health support. By addressing these needs, we can help sustain caregivers in their vital roles and improve their quality of life.
Acknowledgements
The authors wish to express their gratitude towards the vice president of research in Mashhad University of Medical Sciences, the chiefs and staffs of the Health centers and the esteemed participants.
Declarations
Ethics approval and consent to participate
The study protocol was approved by the Ethics Committee of Mashhad University of Medical Sciences (IR.MUMS.REC.1400.019) after obtaining the required permit for the research. The participants provided written informed consent and were assured of confident. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee with the 1964 Helsinki declaration.
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
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