Psychometric properties of the Persian version of Instrument of Professional Attitude for Student Nurses (IPASN)

To evaluate nursing students’ professionalism attitude, it is necessary to use a validated and reliable instrument.


| INTRODUC TI ON
Nursing has changed over the past three decades. For instance, the development of the roles and independence in medical clinics has brought about educational standards and licensing for nurses. At present, there are a growing number of nurses with different specialty in medical clinics (Salmond & Echevarria, 2017). Thus, professionalization has become important issue for nursing practice. Professionalization is defined as the degree of commitment to values and behavioural characteristics of a specific profession (Shohani & Zamanzadeh, 2017). Although professionalization is considered as a framework for determining a single specific kind of job among a social community, the emphasis on commitment to the values might led towards an understanding of a specific work condition (Ghadirian et al., 2014). Throughout the years, several nursing investigators have defined nursing characteristics. Based on the previous studies, encouraging nursing students to acquire professional attitudes and behaviours is believed to be of great importance Karadağ et al., 2007).

| BACKG ROU N D
Professional attitudes in nursing students might develop and form during their studies right before starting their professional services (de Swardt et al., 2017). In this context, one of the most fundamental goals of nursing education should be to teach the students the area of professional identity (Heshmati Nabavi et al., 2014). As such, it is necessary to plan for nursing education in all institutions in a way to develop professional attitudes. In doing so, the capacity for changing the attitude in nursing educational institutes needs to be analysed (Van Graan et al., 2016). On the other hand, one of the most noticeable reasons for studying nurses' attitudes before they begin their services is to find some clues on attitudes and behaviours of those students who will teach in their future professional life. This could be sought by determining the students' attitudes prior to their professional life and to help them realize any potential problems and pitfalls in the future (Karadağ et al., 2016).
Hisar and her colleagues designed a list for nursing students' professionalism attitude namely the Instrument of Professional Attitude for Student Nurses (IPASN). The original questionnaire is in Turkish, and the English version of the questionnaire extensively was used by many investigators (Courtney-Pratt et al., 2015;Heshmati Nabavi et al., 2014;A. Karadağ et al., 2015;Karadağ et al., 2016;Xiao et al., 2017;. The only version of the questionnaire in other languages is the Chinese version, and the psychometric properties of the questionnaire are well documented (Karadağ et al., 2016).
Due to the importance of recognition and evaluation of professionalism attitude among nursing students, this study aimed to translate and validate the questionnaire in Iran. Currently, such a questionnaire is not available in Iran. It was hoped this might help to improve nursing discipline in higher education and in practice.

| The questionnaire
The Instrument of Professional Attitude for Student Nurses (IPASN) includes 28 items rating on a 5-point scale tapping into eight dimensions: Contribution to the increase of scientific information load (6 items); Autonomy (3 items); Cooperation (5 items); Competence, continuous education (3 items); Participation in professional organizations and professional development (3 items); Working in committees (3 items); Community service (2 items); and Ethical codes and theory (3 items) .

| Procedure and translation
The present study was a methodological and validation study. After obtaining permission, the translation process from English into Persian was conducted using the forward-backward method. First, the items were translated into the target language by two experts who had a good command of both languages. Then, two translators re-translated the materials into the original language, that is English.
The translated items were matched with the original items to ensure that the concepts had been successfully conveyed. Afterwards, to check the content and face validity of the instrument, the questionnaires were distributed among five Persian language and literature experts to get their suggestions regarding language-related revisions, use of words and the appropriateness of the items and their placement. Then, the first draft of the Persian version of the questionnaire was pre-tested on ten senior nursing students and the face validity and item combination were then analysed. Additionally, qualitative content validity was examined by a panel of experts.
After applying the required revisions, the final version of the Persian questionnaire was developed and was administered to a sample of nursing students.

| Sample and setting
A multistage stratified sampling procedure was applied to include a representative sample of nursing students in the study. As such, 15 nursing colleges from the whole country (five main regions of the country: north, south, east, west and centre) were randomly selected. Then in each college, a convenient sample of senior nursing students who were willing to participate were entered into the study. For the study purposes, we thought at least 280 students (10 students per item) are needed for exploratory factor analysis (EFA) and similarly 280 students are needed for confirmatory factor analysis (CFA) (Polit & Yang, 2015). However, in practice we recruited 750 students (450 for EFA and 300 for CFA).

| Data collection
The data were collected during March -April 2017. The interviews were conducted in the corresponding hospitals relevant to the above universities during the internship period. The demographic information including age, sex and marital status also was recorded.

| Statistical analysis
1. Validity: Validity of the questionnaire was tested using both exploratory and confirmatory factor analyses.
a. The exploratory factor analysis was performed to explore the factor structure the questionnaire. The Kaiser-Meyer-Olkin (KMO) and Bartlett's test (BT) were performed for sampling adequacy and sphericity of the data. Eigenvalues above 1 and scree plot were used to determine the number of factors.
When the KMO index is higher than 0.60 and Bartlett sphericity test results are significant, it means that the data can be analysed using factor analysis. Loading of 0.3 or above considered acceptable to maintain each item in an extracted factor.
b. The confirmatory factor analysis (CFA) was performed to confirm the factor structure of the IPASN. The CFA model was

Reliability: To determine the internal consistency and stability,
Cronbach's alpha coefficient and intraclass correlation coefficient (ICC) for the whole scale were calculated (Rejeh et al., 2012).
Statistical analysis was provided using SPSS version 16 and LISREL 8. The maximum acceptable type 1 error was considered as 5%.

| The study sample
All 750 nursing students were entered into the study. Of these, data from 450 students were used for exploratory factors analysis and the data from the remaining 300 students were used for confirmatory factor analysis. The characteristics of the study samples are shown in Table 1. The mean age of participants was 23.34 (SD 1.11) years, and more than half (61.86%) were female students. Most participants were single (60.40%). Table 1 presents further information of the study participants.

| Exploratory factor analysis
The KMO value for the data was 0.877, and the results obtained from the Bartlett's sphericity test were satisfactory (p < .0001; χ 2 = 4,739.927) suggesting that the sample was adequate and the distribution of the data was acceptable for exploratory factor analysis. Consequently, factor analysis was conducted and 8 factors with eigenvalue equal or greater than 1 extracted that jointly explained 73.06% of the variance observed. The factor loading ranged from 0.57-0.93. The results are shown in Table 2.

| Confirmatory factor analytic
According to the CFA, the multiple criteria obtained for the data were  Table 2 shows the reliability of the 28-item instrument. The highest Cronbach's alpha was reported as being 0.89. The test-retest reliability approach was conducted on 100 student participants once, just after their main examination and within two weeks after the examination. The intraclass correlation coefficient (ICC) for the questionnaire was reported to be 0.92 and ranged from 0.81-0.98 for sub-factors.

| D ISCUSS I ON
There are many studies conducted on nurses' professionalization.
To conduct such studies efficiently, reliable and valid instruments (e.g. questionnaire) are essential. Therefore, designing, revising and validating a questionnaire to evaluate nurses' professionalization are of great importance for the research community, especially nursing researchers. In this sense, a specific questionnaire concerning nursing students' professionalization (IPASN-P), including 28 items

TA B L E 2 (Continued)
in eight dimensions, was translated into Persian and then the validation conditions were determined. This questionnaire is quite easy to complete and medical staff and nursing students in nursing universities can complete it in less than 15 min. The translation process was carried by experts, following translation principles and paying accurate attention to the cultural semantic matching between the two languages. Therefore, the translation and validation processes comply with the main existing guidelines (Eghbali et al., 2020;Polit & Yang, 2015).
To validate the questionnaire, face validity (qualitative), content validity (qualitative), construct validity (exploratory factor analysis and confirmatory factor analysis) and internal consistency (Cronbach's alpha) were sought. The face validation was approved by asking students to carry out a qualitative analysis. Then, experts were interviewed and the content validity and cultural matching were ensured.
The instrument development process normally begins with EFA and factor structure. Then, the resulting model is verified using a CFA. In the present study, the EFA resulted in an 8-factor model of 28 items for the instrument and the model was confirmed by a CFA.
A major reason for using an EFA is to generate a theory about the essential structures of an instrument and this process is followed by a CFA, which should be performed using data other than those used in the EFA. Therefore, in the present study, the CFA was conducted with a new set of data collected from a sample consisting of 300 subjects (Hung et al., 2010). During the CFA, the goodness of fit was calculated using several variables. The most frequently used indices include NFI, NNFI, AGFI, GFI, RMSEA and CFI, all of which were relatively acceptable.
One of the indices which are commonly used in the evaluation of the convenience of a model is the chi-square (χ2). The chi-square value and degree of freedom (df) for a model could provide normed fit value (χ2/df) where values less than 3.0 indicate a good model fit (Kline, 1998). However, this index is sensitive to sample size and when sample size is more than 200 it is not a valuable index for model fit (Lerman et al., 2010;Limbers et al., 2009). Thus in current study, since sample size was 300, normed fit was not used.
Cronbach's alpha indices were indicative of high internal consistency among the items of the questionnaire; hence, the reliability of the nursing students' professionalization attitude was approved. In a similar study, Hisar  and Xiao (Xiao et al., 2017) reported a reliability index between 0.71 to 0.84-0.67 F I G U R E 1 Results of the CFA: the standardized coefficients for the IPASN to 0.89, respectively. Therefore, the results of this study are in line with that of Hisar's and Xiao in accrediting the total reliability of the questionnaire. However, one should be noticed that using scree plot and eigenvalues are traditional methods and instead it is recommended to use a newer approach such as parallel analysis in the future studies.

| Limitations
Although this study benefited from a good sample size and it contributes to the necessity of practice development and educational needs of pre-licensure nursing students, a few limitations should be acknowledged. Firstly, the sample was recruited from a limited number of nursing faculties. Secondly, we used the English version of the questionnaire for forward-backward translation. Perhaps not using the original Turkish version of the question might be a limitation.
[Correction added on 5 January 2021 after first online publication: The preceding sentence has been amended from 'Perhaps using the…' to 'Perhaps not using the…'.]

| CON CLUS ION
The study findings suggest that the Persian version of 28-item IPASN questionnaire (IPASN-P) is a reliable and valid instrument. Indeed, the questionnaire is worthy of use and further helps to determine the professional attitudes of student nurses.

| CON S ENT TO PUB LIS H
Not applicable.

ACK N OWLED G M ENTS
We thank all participants who made this study possible.

CO N FLI C T O F I NTE R E S T
The authors declare that they have no competing interests.

AUTH O R ' S CO NTR I B UTI O N S
MHK was the study supervisor and contributed to all aspect of the study. ME and FGH collected data. RB was the main investigator and provided the first draft. AM was the study advisor and contributed to the study design, critically reviewed the paper and provided the final draft. RB was the study advisor and contributed to the writing process, and the statistical advisor and contributed to data analysis.
All authors read and approved of the final manuscript.

The University Of Social Welfare and Rehabilitation Sciences Ethics
Committee approved the study. All participants signed informed consent form.

DATA AVA I L A B I L I T Y S TAT E M E N T
The data sets are available from the corresponding author on request.