1. Background
Employee behavior often goes a long way to determine the success or failure of any organization in which they work. Some of these behaviors, such as citizenship behaviors, job performance, and organizational commitment, are socially desirable; while many are improper, negatively affecting organizations, as an example of unethical behavior. 
Unethical behavior can be defined as a behavior that brings harm to, and that is illegal or morally unacceptable to the larger society. By this definition, lying, corruption, cheating, absenteeism, lateness to work, stealing, divulging official secrets, or interpersonal aggression would be examples of such unethical behaviors. These ranges of behavior have the capacity of destroying organization mission and vision (Fagbohungbe Akinbode, & Ayodeji 2012; Mobalaji 2012; Olasupo & Fagbenro 2018). Unethical behavior has continued to be a serious issue in the world and Nigeria. About 45% of the U.S. retailers’ inventory shortage was attributed to employee theft in 2010 (Hollinger & Adams 2010). Furthermore, in 2015, approximately 35% of adult Americans experienced workplace bullying (Workplace Bullying Institute, 2015). 
In Nigeria, the menace of unethical behavior has also gained considerable attention from all concerned stakeholders, especially recently. In particular, the issues of cases involving cybercrime (Chinedu 2012), financial misconduct (Azu 2012), and poor attitude to work (Obinna 2011) have been reported in the newspapers and as well as local and national electronic media. The need to reduce unethical behavior in the workplace, especially in the Nigerian public health sector, can be overemphasized due to its adverse impacts on the organization, employees, and patients (Muafi 2011). 
In the health sector, hospital nurses are a critical set of health workers who have different vital roles, such as medical and administrative work, as well as taking care of and patient care provision. Recently, nurses have continued to engage in unethical behaviors, such as lateness to work, theft, the misappropriation of funds, tardiness, and so on (Bichi 2017). This has continued to have a severe negative implication on the health sector as well as patients’ wellbeing. Role ambiguity and organizational justice have not been given adequate attention in the literature as an antecedent of unethical behavior among nurses.
Sinha & Subramanian (2012) refer to role ambiguity as the degree of uncertainty perceived in accomplishing role requirements or the absence of predictability about the results of role behavior. Onyemah (2008) defined role ambiguity as to the employees’ uncertainty toward their job expectations. Role ambiguity is an unclear condition, emerging because of an inexplicit job description where responsibilities and boundaries are not clearly defined. It is a situation where an individual fails to adequately understand what his job is.
Role ambiguity is the inseparable part of any work environment. It can be deduced from this preceding that the inability of employees to know their work roles could be responsible for unethical behavior among nurses (Soltani et al. 2013). Another variable of interest in this study is organizational justice. Ajala & bolarinwa (2015) defined organizational justice as the perception of individuals and groups regarding fair treatment that they received from the organization and their resultant reactions in behaviors to such perceptions. Employees often assess whether their contributions to the organization match the rewards they receive Niehoff & Moorman (1993). Therefore, when nurses perceive injustice on the part of hospital management, they could engage in unethical behavior in the form of retaliation. 
The present study sought to advance the understanding of the psychological predictors of unethical behavior; thus, we examined role ambiguity and organizational justice as the predictors of unethical behavior among nurses in Nigeria. The study outcomes may provide more insight into reducing or eradicating unethical behavior among nurses in Nigeria.
2. Materials and Methods 
This cross-sectional study employed an ex-post facto research design; because the study variables were present prior to the time of data collection. The independent variables were organizational justice and role ambiguity, while the dependent variable was unethical behavior. A total of 300 subjects participated in this study. The study was carried out in Lagos State Teaching Hospital (LUTH) in Idi-Araba Lagos State, Nigeria. Purposive sampling method was used to select the state (Lagos). Moreover, while convenience random sampling technique was used to select the subjects. 
The required data were collected during three weeks by standardized questionnaires consisting of 4 sections. Section A tapped the sociodemographic characteristics of the respondents, such as age, gender, marital status, educational qualification, and job tenure. 
Section B of the questionnaire tapped the unethical behavior, which was measured using the 37-item Unethical Behavior Scale (UBS) by Kaptein (2008). Sample of the items read is as follows: “abusing or misusing confidential or proprietary information of the organization’’ and “violating document retention rules’’. The respondents expressed their degree of agreement on a 5-point Likert-type scale, ranging from very strongly disagree (1) to very strongly agree (5). A high score on this measure indicates high unethical behavior, while low scores indicate low unethical behavior. Kaptein (2008) has reported reliability of 0.75 for this scale. The reliability coefficient of the scale in the present study was equal to 0.82. 
Section C was the 6-item Role Ambiguity Scale (RAS) developed by Rizzo, House & Lirtzman (1970). This scale contained three positively worded items and three negatively worded items. The negative items performed as a separate factor from the positive items. Sample of the items on the scale reads was “I know that I have divided my time properly’’ and “I know what my responsibilities are’’. The scale used a 5-point Likert-type scale, ranging from 1 (strongly disagree) to 5 (strongly agree), indicating the degree to which the item describes them. High scores of the scale suggest high role ambiguity while low scores indicate low role ambiguity. Niehoff & Moorman (1993) reported a reliability coefficient of 0.82 for this tool. In this study, a Cronbach’s alpha coefficient of 0.86 was obtained. 
Section D was measured using the 18-item Organizational Justice Scale (OJS) by Niehoff and Moorman (1993). Sample of the item include “I consider my workload to be quite fair’’ and “generally, the rewards I receive here are quite fair’’. The respondents rated the items on a Likert-type scale, ranging from 1 (to a minimal extent) to 5 (to a vast extent). High scores of the scale reflect high organizational justice; while a low score indicates low organizational justice. Cronbach’s alpha coefficient for the scale was calculated as 0.73 in this study. 
Firstly, permission from the Ethical Committee of the Obafemi Awolowo University was granted to conduct the study. Permission to carry out the study was also granted by the Hospital management after the required protocol was followed. Then, the researcher and one research assistant who was trained on data collection explained the research purpose to the prospective study participants. The informed consent forms (which contained information like how to guarantee the confidentiality and anonymity of the identities of the participants) were signed by the volunteer study participants. Next, questionnaires were randomly provided to the study participants (either in their various wards/offices or hospital premises). However, most of the study participants filled the questionnaires after working hours, due to the busy nature of their work. The researchers were available to collect the questionnaires after the working hours from the respondents. This technique was useful as the questionnaires were adequately completed and retrieved from the respondents.
The attained data were scored, processed, and analyzed in SPSS. Descriptive and inferential statistics were used to analyze the collected data. Descriptive statistics were used to describe the study participants’ characteristics; while, the inferential statistics (multiple regression) was used to test the study hypothesis. 

3. Results
The study participants consisted of 300 nurses. They comprised 201 females (71.9%) and 99 males (28.1%) with a Mean±SD age of 31.66±3.13 years. Moreover, 116 (38.7%) were single, 140 (46.7%) were married, and 44 (14.7%) were separated. In addition, 54 (18.0%) of the samples had senior secondary school certificate, 136 (45.3%) had Ordinary National Diploma/Nigerian Certificate of Education, 60 (20.0%) had Higher National Diploma/Bachelor of science, and 50 (16.7%) had master’s degree. Data regarding the work experience of the subjects revealed that 88 (29.3%) had work experience of below 5 years, 88 (29.3%) had 5-9 years of such experience, 64 (21.3%) had 10-14 years of experience; while 60 (20.0%) reported above 15 years of work experience (Table 1).

The achieved results revealed that role ambiguity and organizational justice significantly and jointly predicted unethical behavior in nurses (F2.296=4.179, P<0.05, R2=0.228). It was inferred that about 22.8% of the variation observable in the unethical behavior of nurses could be accounted for by role ambiguity and organizational justice. Furthermore, the independent prediction of unethical behavior by role ambiguity (β=0.229; t=3.157; P<0.01) and organizational justice (β=-0.317; t=-2.182; P<0.05) was statistically significant (Table 2). 

4. Discussion
The current study investigated the predictive impact of role ambiguity and organizational justice in the development of unethical behavior among nurses. It was found that role ambiguity and organizational justice predicts unethical behavior in nurses. The study finding was in line with that of Nasib (2017), who examined the relationship between unethical behavior, organizational justice, and role ambiguity. Nasib argued that justice and role ambiguity predict unethical behavior among nursing students. 
The study was also consistent with Demore (2012) findings, suggesting that injustice perception and role ambiguity predict unethical behavior among college students. The justification for this finding could be related to the understaffing of nurses in Nigeria hospitals, especially the government-owned ones; this confuses nurses about their stated roles. A nurse, working in a particular position in a hospital on day, might work in a different position the next day. Despite this role ambiguity, nurses believe that hospital management has not been fair to them. This engages typical Nigerian nurses in unethical behaviors, such as lateness to work, receiving money from patients before the treatment, and other harmful vices.
This result has serious implication for psychologists as well as the government. To reduce the menace of unethical behavior among nurses, role ambiguity, and organizational justice need to be critically considered. The study, therefore, recommends that psychologists and managers develop intervention programs tailored to resolve the role ambiguity and improve organizational justice among nurses; as a result, the menace of unethical behavior among this group of essential workers will be reduced. 
It is also recommended that the government improve the welfare packages of nurses, such as improved wages, conducive working environment, and other social amenities. This must be performed in a way that nurses perceive high organizational justice which invariably reduces their unethical behavior. The international implications of the study findings could negatively affect the integrity of nurses who are burdened with the responsibility of providing care to patients. This could also mean that patients would no longer have any confidence in the nursing profession and this could reduce the rate at which people go to the hospital to receive care; thus other forms of healthcare alternative could be strengthened.
This study faced some limitations; first, any study that is conducted within a limited scope has the challenge of generalizability of the results. Therefore, the findings of this study may be argued to be relevant within the scope of the particular setting of this study; this is because the sample size was relatively small. Furthermore, we only included nurses in one state hospital; therefore, generalizability of the study findings to all nurses in Nigeria is impossible. However, the study findings still imply unethical behavior studies in Nigeria. 
Second, the subjects’ attitude toward completing the questionnaires was also a significant challenge. It took several days/weeks before the questionnaires were returned; as the study participants claimed they were too busy to fill a questionnaire. It is advised that future studies be conducted with a large sample size that cuts across different nurses in Nigeria. Also, future research can improve the method of data collection; e.g. using qualitative methods, such as interviewing, focus group discussion, and observational methods. 
In conclusion role ambiguity and organizational justice predicted unethical behavior. This result, therefore, implies that the authorities and hospital managers of Nigeria should design an intervention program tailored toward resolving role ambiguity and improving organizational justice to help to reduce the menace of unethical behavior among these nurses.
Ethical Considerations
Compliance with ethical guidelines
Permission was granted from the Ethical Committee of the Obafemi Awolowo University to carry out the study. Permission to carry out the study was also granted by the Hospital management. The study participants signed the informed consent forms (which contained information such as how to guarantee the confidentiality and anonymity of the identities of the participants). 
Funding
This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
Conflict of interest
The authors declared no conflicts of interest.
Acknowledgments
The author appreciates the nurses in the Lagos State Teaching Hospital who despite their tight working schedule, participated in the present study. 


References