A Pilot Study on Organizational Justice Scale for Student Organization: Result of Reliability and Validity

Article history: Organizational justice is an individual's fair perception of organizational decisions taken by its leaders. Researchers conducted a psychometric analysis to determine the validity and reliability of the organizational justice scale. The organizational justice scale is based on three dimensions: distributive justice, procedural justice, and interactional justice. The pilot study involved 36 students who were members of the Universitas Muhammadiyah Purwokerto, Indonesia. The validity test uses content validity, product-moment item selection while measuring reliability using Cronbach's alpha which is analyzed using SPSS version 25. The analysis results prove that 32 items are feasible and reliable with Cronbach's alpha value of 0.948. Thus, the organizational justice scale can be used for research on student organizations.


INTRODUCTION
Since 1970 civil society organizations have emerged and developed rapidly in both developed and developing countries, both in number, size, and mission capability. An organization will always experience ups and downs in its journey. Some organizations are multiplying, but many organizations cannot develop or do not have time to create and even die (Wahab, 2015).
Organizational justice cannot be separated from the basic theory of equity (equity theory). This theory states that people compare the ratio and the results of the work they do, the comparison is, for example, rewards and promotions with the effort they give to organizations or companies or the same ratio of others, this theory was created to predict the effect of rewards on human behavior (Adams, 1963). Individuals will make specific comparisons of a job that he does. These comparisons significantly affect the stability of the individual's thoughts and feelings regarding rewards and produce changes in motivation and behavior in individuals (Adams, 1963).
Researchers have developed instruments for measuring organizational justice with various versions. (Colquitt, 2001) developed an organizational justice scale to measure perceptions of organizational justice based on four dimensions: distributive, procedural, interpersonal, and informational. This scale is widely used for research in various countries with a variety of research subjects. (Shibaoka et al., 2010) developed the dimensions and validated the organizational justice scale in Japan. This study involved 229 employees, and the results showed the Organizational Justice Scale -Japan is a reliable and valid instrument and is suitable to be used as a predictor of the health of Japanese employees. The test of the validity and reliability of the organizational justice scale was also conducted in Korea involving 303 workers. The results suggest that the instrument can be used in future occupational health studies (Park et al., 2018).
The psychometric analysis was carried out on the workers, which is different from the study we did. We conducted a psychometric study on an organizational justice scale with students from Islamic-based student organizations as subjects.

THEORITICAL FRAMEWORK Organizational Justice
The basic theory of equity is a theory of equity (equity theory). This theory states that people compare the ratio and the results of their work, the comparison, for example, rewards and promotions with the effort they give to the organization or company or the same ratio of others. This theory was created to predict the effect of tips on human behavior (Adams, 1963).
Individuals will make specific comparisons of a job that he does. These comparisons significantly affect the stability of the individual's thoughts and feelings regarding rewards and produce changes in motivation and behavior in individuals (Adams, 1963).
Justice can be interpreted as a condition where people receive according to what is their right. It does not mean the same, the same taste, but the size of the income based on the sacrifices given (Busro, 2018). Justice is closely related to the position, role, function, position, structure, level of education, the outpouring of thoughts, energy, and time in achieving goals contained in the organization. Organizational justice can be defined as the way employees determine whether the company treats its employees fairly in their work or not (Niehoff & Moorman, 1993).
From some of the explanations above, it can be concluded that organizational justice is a personal assessment of the ethics and ethics of management behavior, which means that in producing organizational justice, management needs to understand employees' views. How employees determine whether the company is working somewhat when treating employees.
The dimensions of organizational justice are distributive justice, procedural justice, and interactional justice (Robbins et al., 1982). Distributive justice is a perception of fairness of results in the number and awards received between individuals or employees; this justice also describes how the perceived results obtained by individuals are by the needs or contributions of the results of their work in the company. Procedural justice is a perception of justice from the decision-making process used to determine the effects or rewards that will later be distributed. Interactional justice is an employee's perception of fairness in aspects of interactions that are not recorded from the procedural. So, in this study, the focus is on the three dimensions proposed by Robbins & Judge.
The description explains the concept of organizational justice in the context of work organization. Only a few research results discuss organizational justice in the context of non-profit organizations. Kovacevic et al., 2013 examine organizational justice in the context of education. The implications of organizational justice in student organizations are included in the construct of peer justice, namely measuring the behavior of people who do not have formal authority towards others internally to the group. Peer justice predicts interpersonal teamwork tasks and processes and predicts organizational performance (Cropanzano & Molina, 2015). Thus peer justice can reflect the dynamics of student organizations.

RESEARCH METHODOLOGY
This research is a quantitative approach, namely a psychometric test on the organizational justice scale in student organizations. The organizational justice scale is formulated based on the dimensions of distributive justice, procedural justice, and interactional justice (Robbins & Judge, 2007). Thirty-six student members of the Islamic student organization were involved in this study.
Validity can also be interpreted as the extent to which the test measures what it is intended to measure (Ihsan, 2015). The validity in this study is content validity. Content validity focuses on what elements are in the measuring instrument (Coaley, 2010).
The item selection in this study uses the SPSS (Statistical Product and Service Solution) version 25.00 program. It is carried out to select items that pass the section provided that the total corrected item value is > 0.30 in the SPSS output table. For item selection criteria based on the output results in the corrected item complete correlation table, the correlation coefficient limit is 0.30. All items that reach a correlation coefficient of at least 0.30 are interpreted as adequate discriminatory power. Then the item whose correlation coefficient is less than 0.30 can be interpreted as an item that has low discrimination power (Azwar, 1994).
Reliability is the extent to which measurement results using the same object will produce the same data (Sugiyono, 2015). In this study, to find out that the scale can be trusted as a data collection tool, reliability was carried out using the Alpha Cronbach technique using the SPSS (Statistical Product and Service Solution) program version 25.00).

RESULTS AND DISCUSSION
Content validity in the development of this measuring tool is used to see the relevance of each item developed by involving one expert. Content validity explains a measuring instrument substantively or called substantive validity, which focuses on the conceptualization of variables according to the literature review. The result of the content validity test is an assessment of the feasibility of the measuring instrument. In this study, the definition of a concept, operational definition, and representation of the number of items are considered good or following the theory used. The results of the content validity test are also shown in the blueprint in  Table 1 shows that the organizational justice scale for students can be measured through 40 items. Furthermore, item selection from the student organization justice scale can be seen in table 2. All items that reach a correlation coefficient of at least 0.30 are interpreted as sufficient discriminatory power. Then the item whose correlation coefficient is less than 0.30 can be interpreted as an item with low discrimination power (Azwar, 1994). The discriminant items move from 0.341 to 0.803. It can be concluded that 32 items have high discriminatory power, so 32 items of organizational justice can measure the fairness of student organizations in Indonesia.
Furthermore, to determine the reliability of the organizational justice scale, a reliability test was conducted using the Alpha Cronbach technique with a result of 0.948. The instrument is reliable, namely high consistency, to measure the organizational justice variable of Indonesian students.
The results of this psychometric analysis prove that the organizational justice scale can be applied in student organizations. There are not many research results that examine the implications of justice in student organizations. Therefore, the findings of this study are helpful for future researchers interested in studying organizational justice in student organizations.
The results of this pilot study support the opinion that organizational justice is also called peer justice, namely the concept of justice that is applied among members of a group who do not have authority (Cropanzano & Molina, 2015). Peer justice is a new variant of the concept of organizational justice. Peer Justice also has three dimensions, namely: 1) peer distributive justice, namely the shared perception that organizational members receive what they deserve based on their contributions; 2) Partner procedural justice, namely the extent to which members of the organization use fair procedures in the decision-making process; 3) Peer interactional justice, namely interpersonal justice shown by members of the organization treating each other (Cropanzano et al., 2011).

CONCLUSION
The results of the psychometric analysis can be concluded that the organizational justice measuring instrument can be used in student organizations in Indonesia.