Discussion
This study aimed to investigate the different psychometric properties of
the Justice Perception of Performance Appraisal among the Iranian nurses
according to the guidelines proposed by Incarnate Word University. The
results of the present study showed that the Justice Perception of
Performance Appraisal is a valid and reliable instrument for evaluation
of this variable in the socio-cultural context of Iran.
Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA)
were used to determine the construct validity of the Justice Perception
of Performance Appraisal. The main purpose of factor analysis is to
summarize a large number of variables into a limited number of factors
so that there is the least amount of missed data (18). In this study,
the same four factors which were introduced in the main framework were
also obtained with acceptable factor loading values. The purpose of
exploratory factor analysis is to discover the dimensions of the
variable to determine the dimensions of the scale, standardizing the
instruments or tests, reducing the dimensions, and evaluating the
homogeneity and diversity regarding the construct validity. In this
study, the results of exploratory factor analysis indicated the
establishment of the four factors of procedural justice, distributive
justice, interpersonal justice, and informational justice covering
57.71% of the variance.
Confirmatory factor analysis was also applied to answer the following
question: ”can the data in this study confirm the theoretical model
which was proposed by the developers of the instrument?”(19). As a
result, all the 56 items of the instrument were used as the variables in
this study. Given that x2/df = 2.23, the quality of
the model was confirmed to allow the assignment of the 56 items to the
four theoretically determining factors. Moreover, chi-square,
goodness-of-fit index, root mean square residual, root mean square error
of approximation, three Bentler-Bont indices, Tucker-Lewis’s index, and
comparative fit index were used to evaluate the fitting factor.
Accordingly, all these values were indicative of optimal fit. Fit
indices of confirmatory factor analysis in the original study which was
conducted by the developers of the scale were as follows: RMSEA = 0.13,
RMR = 0.049, CFI = 0.95, GFI = 0.86, and Chi-Square(df) = 29.2 (29) (8).
Cranach’s alpha values of 0.7 or above indicate internal stability. In
the present study, the Cranach’s alpha coefficient and the intra-class
correlation of the instrument were 0.97 and 0.95, respectively, which
indicates that the questionnaire understudy has acceptable internal
stability for Iranian nurses. Nevertheless, Cranach’s alpha coefficient
was reported above 0.87 for all the subscales by the original
developers, indicating acceptable reliability of the original
questionnaire (8). According to the results of the present study, it can
be stated that the Justice Perception of Performance Appraisal is a
reliable, repeatable, and adequately stable instrument.
In addition to the desired reliability, the Justice Perception of
Performance Appraisal provides multidimensionality which includes four
areas of procedural or systemic justice, distributive justice,
interpersonal justice, and informational justice. Compared to the
organizational justice framework which was developed by Niehoff&Moorman
(20), this questionnaire has proposed four main dimensions and more
items that indicate higher validity of the instrument.
Although the primary version of this instrument has been used in
previous studies (5,21). in Iran, the researchers have only provided
some information about the dimensions and the number of items. In other
words, they provided insufficient information regarding the analysis of
the validity and reliability of Justice Perception of Performance
Appraisal (5,21).
Rakhshany Zabol et al. also examined the organizational justice among
nurses using Niehoffand Moorman’s proposed scale which helps evaluate
organizational justice in 20 items and 3 dimensions (10). The authors
had calculated the reliability of this scale in their previous study on
a sample of nurses with a Cranach’s alpha coefficient of 0.96.
Researchers have only reported the content validity of the instrument
based on the opinions of 10 experts but provided no information about
the process of assessing the content validity (22). In another study by
Mohamed, the relationship between organizational justice and quality of
performance among healthcare providers was examined using a
researcher-made questionnaire. However, since there is not enough
information about the development and psychometric properties of this
instrument, it is not possible to have an accurate opinion about its
scientific validity and reliability (11).
The majority of the studies related to measuring the nurses’ perception
of justice in Iran provide little knowledge about the validity and
reliability of research instruments. The validity and internal stability
of the Justice Perception of Performance Appraisal showed that the
instrument has been translated appropriately and fluently and also the
nurses did not face any ambiguity while answering the questions.
Besides, the items of the questionnaire were racially and culturally
insensitive which can be considered as a distinctive feature for this
questionnaire. Although the present study confirms the psychometric
properties of the instrument, it is necessary to conduct similar studies
using this instrument in the Iranian context to increase the
generalizability of the findings. This is the first time that such a
scale is validated for nurses’ performance appraisal; hence, it is
suggested to investigate the invariance of the factors in this
instrument between different groups of respondents in future researches.