Introduction
One of the main concepts in nursing is care. This crucial concept for nurses was first proposed by Leininger in the 1950s. Since then, care is considered an essential part of the nursing practice [1]. As the largest group of caregivers in the health care system, nurses provide continuous care to patients and their services play a vital role in achieving the goals of health service delivery systems and patients’ satisfaction [2] as nursing care is one of the main components of health care services [3]. 
One of the issues in nursing care is the intention of nurses to take care of infectious patients. In early 2020, the World Health Organization (WHO) announced a new pandemic disease called the Coronavirus Disease 2019 (COVID-19) [4] According to the statistics by WHO, until July 13, 2021, a total of 187 172 223 people were infected with COVID-19 and 3 796 173 people worldwide died because of this disease. In Iran, 3 394 279 people were infected and 8 641 people died because of COVID-19 [5]. In the current situation, many hospitals are facing conditions, such as an increase in the number of patients, an increase in workload, psychological stress, and financial problems [6].
Among the members of the treatment staff, nurses play a vital role in the front line of the COVID-19 outbreak [7]. In addition to job stress, nurses are also faced with factors that affect their intention to care [6]. According to the evidence during the pandemic period, because of various reasons, such as fear of transmission, infecting themselves and their family members, the pressure from family members, and the lack of personal protective equipment, many members of the medical staff, especially nurses, left their jobs. As a result, the health care system faced a lack of staff in many hospitals. Meanwhile, the above-mentioned factors affect nurses’ intention to take care of such patients [6, 8].
In the nursing profession, the theory of planned behavior explains the intention to perform care. Accordingly, the intention to provide care includes three dimensions, namely attitude, subjective norms, and perceived control [9]. Culture, beliefs, customs, and norms can have different effects on patient care; however, some studies have shown that social norms have a weak correlation with behavioral tendencies [10]. Social norms can also predict behavioral intention; however, a precise relationship between behavioral beliefs, control, and intention to care for patients in different conditions has not yet been reported [11, 12, 13, 14, 15, 16, 17, 18]. Increasing the intention to care for patients is a vital issue in nursing that has recently been considered [14]. More important is the investigation of these relationships in critical conditions; for instance, the spread of the COVID-19 disease may have different results from non-critical conditions. Therefore, a more detailed examination of the relationship between these factors can help determine the effective factors in nurses’ intention to care for patients in such conditions. Accordingly, this study aims to determine the effective factors in nurses’ intention to care for patients with COVID-19. 
Materials and Method 
This cross-sectional study was conducted using convenience and targeted sampling methods in 2020 with a sample size of 200 nurses employed in selected hospitals in Tehran City, Iran (3 hospitals) and Amol City, Iran (3 hospitals). The sample size was estimated at 200 people by considering 46 items, 6 factors, the effect size of 0.27, the test power of 80%, and α of 0.05 via the sample size estimation formula [19]. In this way, considering the high workload of nurses and the limitations in data collection, 100 nurses were selected from each city (3 hospitals in each city). The inclusion criteria included the intention to participate in the study, being employed in the selected hospitals, and being the ward of COVID-19 patients. The exclusion criteria included nurses’ lack of incentive to participate in the study, less than 6 months of experience, a history of receiving psychotropic drugs during the past year, being a student, and having a managerial position. Given the restrictions of the COVID-19 pandemic, sampling was done online. The online questionnaire link was prepared with a Google Doc link and sent to eligible people via social networks, such as Telegram, WhatsApp, and email. The consent form was also in the same link.
The first part of the questionnaire comprised demographic questions to collect information regarding the participants’ age, gender, marital status, education level (bachelor's degree, master's degree, and doctorate), employment status (project, contract, contractual, and official), and work experience. 
In the second part, the Persian version of the Nurses’ Intention to Care Scale (P-NICS) questionnaire was used to measure the intention to care for COVID-19 patients. This questionnaire contains 46 items in 6 factors (components), scored on a 7-point Likert scale from “Very Little” to “Very much”. The factors of this questionnaire include positive and negative behavioral beliefs, positive and negative control beliefs, and family and occupational mental norms. In the end, the question “how willing are you to nurse patients with COVID-19?” was asked separately by the nurses in a graded range from 1 (not at all willing) to 7 (completely willing). The obtained scores were considered a dependent variable. This questionnaire was psychometrically evaluated by Rahmatpour and colleagues among Iranian nurses and the Cronbach α reliability coefficient, the MacDonald omega coefficient, and the composite reliability was reported to be above 0.80 [9].
The completed questionnaire data was extracted in an excel file and analyzed via the SPSS software, version 26. Descriptive statistics were used to evaluate the demographic characteristics. The Kolmogorov-Smirnov test was used to check the normal distribution of the continuous quantitative data. Simple linear regression was used to analyze the predicting variables of intention to care. Also, the variables that were significant in simple linear regression were simultaneously tested in multiple linear regressions. The significance level of all tests was considered less than 0.05. 
Results 
Considering that the data was provided to the nurses of the wards via a web link, 225 nurses viewed the questionnaire link and 200 nurses answered it completely (89%). Subsequently, the data were analyzed. The average age of the participants was 33.02±8.38 years and most of them were female (70.5%). The majority of participants were married (60.5%) and 46.7% of the nurses were officially employed (Table 1).


Result of simple linear regression
Linear regression analysis showed that gender variable (B=0.7, β=0.15, P=0.02) had a significant and positive relationship, meaning that female nurses tended to care more. The results of the linear regression showed that for each level increase in responding the items of positive behavioral beliefs factors (B=0.10, β=0.51, P<0.001), family subjective norms (B=0.13, β=0.43, P<0.001), occupational subjective norms (B=0.10, β=0.27, P<0.001), and positive control beliefs (B=0.09, β=0.21, P=0.002) had a significant and positive relationship in predicting the intention to care. On the other hand, for the increase of each level in responding to the items of factors of negative control beliefs (B=-0.06, β=-0.30, P<0.001) and negative behavioral beliefs (B=-0.13, β=0.22, P<0.001), a significant and negative relationship was observed in predicting the intention to care (Table 2).


Result of multiple linear regression
According to Table 2, adjusted regression analysis demonstrated that based on the remaining variables in the model, for each level increase in responding the items of positive behavioral beliefs factors (B=0.06, β=0.34, P<0.001), negative control beliefs (B=-0.06, β=-0.32, P<0.001), family subjective norms (B=0.06, β=0.22, P<0.001), and occupational subjective norms (B=0.04, β=0.11, P=0.04), the intention to care in patients with COVID-19 was significant and predictable. This model had 43% explanatory power (Table 2). 
Discussion
In this study, the effective factors in nurses’ intention to care for patients with COVID-19 were examined. Among the factors, positive behavioral beliefs, negative control beliefs, family subjective norms, and occupational subjective norms showed 43% predictive power of the score of the factors that influence nurses’ intention to care for patients with COVID-19. The results of the linear regression showed that positive behavioral beliefs can significantly and positively predict the intention to care among Iranian nurses. This result is consistent with Rahmatpour’s and Lee's studies. Factors, such as promoting self-efficacy, promoting self-confidence, and fulfilling the role of a nurse caregiver as positive behavioral beliefs with an impact on the attitude dimension can play a role in the intention of nurses to care for COVID-19 patients [9, 20]. Simultaneously, the results reported in this study regarding the concepts of self-efficacy and increasing knowledge, which can positively and significantly predict the intention to care, are in contrast with the results reported in the study by Talbot et al. [21]. Negative control beliefs negatively and significantly influenced the intention of nurses to care for patients with COVID-19. According to Iranian nurses and considering the contagious nature of COVID-19, fear of infection, increased work pressure, fear of nurses’ family members from COVID-19, and being isolated because of caring for patients with COVID-19 showed a negative effect on nurses’ intention to care for these patients [9]. The results reported in this study are in contrast with the study of Talbot et al. [21]. The reason for such contradictory results can be attributed to the cultural differences and different sampling methods.
Family subjective norms, which positively and significantly showed the ability to predict the intention of nurses to take care of patients with COVID-19, were expressed by the nurses whose parents, siblings, spouses, and friends of nurses consider taking care of COVID-19 patients as a kind of positive norm and encourage nurses in performing this role [9]. Also, this dimension affects the intention to care in nurses with the effect of subjective norms [20] and it should be acknowledged that the caring role of nurses is considered among the defining roles of this profession.
According to the results of the present study, work subjective norm has a positive and significant relationship in predicting the intention to care in nurses. This dimension, similar to the previously mentioned dimension, can explain the intention to care by influencing subjective norms [20]. The factor-analysis study by Rahmatpour et al. was called occupational subjective norms. It was expressed by the nurses in the sense that supervisors and senior managers of the treatment system encourage nurses to take care of COVID-19 patients, and for this reason, this dimension has a positive and significant effect on predicting the intention to care in nurses [9]. The results reported in the present study regarding the subjective dimensions were consistent with the results reported in Talbot’s study, which was conducted on nurses to care for alcohol-dependent clients [21]. However, the results of the present study about the dimensions of family subjective norms and occupational subjective norms are inconsistent with the results reported in Lee et al.’s study, which means that in Iranian nurses, no pressure exists from the society and family members (parents, spouses, brothers and sisters, and friends) to care for patients with acute infectious diseases, such as patients with COVID-19; also, taking care of these patients in the current situation is considered a positive and strengthening norm [20].
The results showed that factors, such as behavioral beliefs, control, and social norms had a significant impact on nurses’ intention to care for patients with COVID-19. One of the strengths of this study is the investigation of the effect of psychological and social factors on nurses’ intention to care. The limitations of this research are the lack of studies in the field of intention to care during the COVID-19 pandemic, collecting information via a self-report questionnaire that some people may refuse to provide real and realistic answers. This research was conducted cross-sectionally, which makes it difficult to conclude causality and to increase the validity of the study; therefore, longitudinal studies are recommended. Also, selection bias is one of the critical limitations of online data collection.
Conclusion 
According to the findings, psychological and social factors influence nurses’ intention to care for patients with COVID-19. Considering that improving the intention to care improves the quality of care, health and treatment managers must pay special attention to the psychological and social factors that affect nurses’ intention to care. 

Ethical Considerations
Compliance with ethical guidelines
The following items were placed on the first page of the designed link: the objectives of the study, the study’s code of ethics, assurance of participants’ anonymity, the confidentiality of the information, and the optionality of participation. This study was approved by the Research Ethics Committee of Mazandaran University of Medical Sciences (IR.MAZUMS.REC.1398.1267).

Funding
The Research and Technology Vice-Chancellor of Mazandaran University of Medical Sciences is the financial sponsor of this research.

Authors' contributions
Conceptualization and supervision: Daniyal Kohistan, Esmail Hosseinzadeh and Mobeen Mohammadinejad; Methodology and data analysis: Hamid Sharifnia;; Data collection: Sana Shahrabadi and Masoume Asid Ali; Review, writing of the original draft, revision and editing: all authors.

Conflict of interest
The authors declared no conflict of interest

Acknowledgments
We sincerely thank and appreciate all the researchers whose studies were used in the current research

References

1. Ghahramanian A, Rassouli M, Zamanzadeh V, Valizadeh L, Asghari E. Good nursing care: Rodgers’ evolutionary concept analysis. Nurs Pract Today. 2020; 7(1):21-9. [DOI:10.18502/npt.v7i1.2295]
2. Banan SHAE. Nurse managers practices and its relation to staff nurses autonomy and satisfaction at a selected hospital. 2020; 10(05):15-23. [DOI:10.15520/ijnd.v10i05.2940]
3. Karaca A, Durna Z. Patient satisfaction with the quality of nursing care. Nurs Open. 2019; 6(2):535-45. [PMID]
4. Phelan AL, Katz R, Gostin LO. The novel coronavirus originating in Wuhan, China: Challenges for global health governance. JAMA. 2020; 323(8):709-10. [PMID]
5. World Health Organization. WHO Coronavirus (COVID-19) dashboard. Geneva: World Health Organization, 20201. [Link]
6. Sharif Nia H, Arslan G, Naghavi N, Sivarajan Froelicher E, Kaveh O, Pahlevan Sharif S, et al. A model of nurses’ intention to care of patients with COVID-19: Mediating roles of job satisfaction and organisational commitment. J Clin Nurs. 2021; 30(11-12):1684-93. [PMID] [PMCID]
7. Liu Q, Luo D, Haase JE, Guo Q, Wang XQ, Liu S, et al. The experiences of health-care providers during the COVID-19 crisis in China: A qualitative study. Lancet Glob Health. 2020; 8(6):e790e8. [DOI:10.1016/S2214-109X(20)30204-7]
8. Tzeng HM. SARS infection control in Taiwan: Investigation of nurses’ professional obligation. Outcomes Manag. 2003; 7(4):186-93. [PMID]
9. Rahmatpour P, Sharif Nia H, Sivarajan Froelicher E, Kaveh O, Pahlevan Sharif S, Taghipour B. Psychometric evaluation of Persian Version of Nurses’ Intention to Care Scale (P-NICS) for patients with covid-19. Int J Gen Med. 2020; 13:515-22. [PMID] [PMCID]
10. Armitage CJ, Conner M. Efficacy of the theory of planned behaviour: A meta-analytic review. Br J Soc Psychol. 2001; ;40(Pt 4):471-99. [PMID]
11. Tortumluoğlu G. [Hemşirelik bakımında kültürel yaklaşım ve önemi (Turkish). J Hum Sci. 2006; 8(1):1-12. [Link]
12. Scholes J, Moore D. Clinical exchange: One model to achieve culturally sensitive care. Nurs Inq. 2000; 7(1):61-71. [PMID]
13. Kilic SP, Besen DB, Tokem Y, Fadiloglu C, Karadag G. An analysis of the cultural problems encountered during caregiving by the nurses working in two different regions of Turkey. Int J Nurs Pract. 2014; 20(3):310-9. [DOI:10.1111/ijn.12152] [PMID]
14. Lachman ME. Perceived control over aging-related declines: Adaptive beliefs and behaviors. Curr Dir Psychol Sci. 2006; 15(6):282-6. [DOI:10.1111/j.1467-8721.2006.00453.x]
15. Ko NY, Feng MC, Chiu DY, Wu MH, Feng JY, Pan SM. Applying theory of planned behavior to predict nurses’ intention and volunteering to care for SARS patients in southern Taiwan. Kaohsiung J Med Sci. 2004; 20(8):389-98. [DOI:10.1016/S1607-551X(09)70175-5]
16. Jeffreys MR. Development and psychometric evaluation of the transcultural self-efficacy tool: A synthesis of findings. J Transcult Nurs. 2000; 11(2):127-36. [PMID]
17. Godsey SR. Student perceptions of professional identity and cultural competence [PhD dissertation]. Minneapolis: University of Minnesota; 2011. [Link]
18. Clark MJD. Community health nursing: Caring for populations. New Jersey: Prentice Hall; 2003. [Link]
19. Westland JC. Lower bounds on sample size in structural equation modeling. Electron Commer Res Appl. 2010; 9(6):476-87. [DOI:10.1016/j.elerap.2010.07.003]
20. Lee J, Kang SJ. Factors influencing nurses’ intention to care for patients with emerging infectious diseases: Application of the theory of planned behavior.Nurs Health Sci. 2020; 22(1):82-90.  [PMID]
21. Talbot AL, Dorrian J, Chapman J. Using the Theory of Planned Behaviour to examine enrolled nursing students’ intention to care for patients with alcohol dependence: A survey study. Nurse Educ Today. 2015; 35(11):1054-61. [PMID]