Development of the Nurse Attitude Scale short form: Factor analysis in a large sample of Japanese psychiatric clinical staff
*Fujika Katsuki, RN, PhD, School of Nursing, Nagoya City University, 1 Kawazumi, Mizuho-ku, Nagoya 467-8601, Japan. Email: email@example.com
The Nurse Attitude Scale (NAS) measures nurses' Expressed Emotion. A short form of the NAS was developed and its reliability and validity examined. After performing factor analysis using 1252 samples, three factors were extracted. Cronbach's α for individual subscales was 0.852 for Hostility, 0.846 for Criticism and 0.645 for Positive Remarks. There was a significant correlation between individual subscales in the NAS short form and corresponding subscale in the Maslach Burnout Inventory (P < 0.001). The NAS short form seems to have acceptable reliability and validity.
STUDIES ON EXPRESSED Emotion (EE) have been conducted on the families of patients with schizophrenia.1 Measurement of EE has also proven effective to assess relationships between psychiatric inpatients and nurses of the wards.2 For long-term inpatients, ward clinical staff spend the most time with patients, more so than the family, and the emotional attitude of clinical staff towards a patient is predicted to have some effect on the course of the patient's illness. In cases of nurses, in particular, most are engaged in the care of inpatients, which means that they are committed to the care of patients with relatively severe psychiatric disorders. Therefore, we developed the Nurse Attitude Scale (NAS) based on the Family Attitude Scale (FAS).3,4 The FAS, which measures the EE of family members, is a 30-item self-report inventory. The Japanese version of the FAS was modified into the NAS by changing some of the phrasing to make it more suitable for nurses. The NAS is also a 30-item self-report inventory. The NAS measures nurses' EE, and its reliability and validity have been verified previously.3 People working in a variety of fields are involved in the care of patients with psychiatric disorders in a team medical practice, and it is considered important to evaluate their emotional attitude toward patients.
The purpose of this study was to establish a valid and reliable self-administrable scale to measure clinical staff's EE with fewer questions than in previous scales which can more easily be used in psychiatric settings in Japan.
Two questionnaires were administered to psychiatric clinical staff in this study. From September to November in 2005, we asked the head of each institution located in Hokkaido, Niigata, Aichi, Fukuoka, Nara, Kumamoto and Hiroshima in Japan, to distribute the questionnaire to employees and confirm an autonomous decision as to participation. The questionnaire was answered anonymously and returned.
Data were obtained from 1252 subjects in 9 Japanese psychiatric hospitals. The subjects were all psychiatric clinical staff members, consisting of 408 males (32.6%) and 798 females (63.7%), while the sex of 46 subjects was unknown. The overall mean years of clinical experience (±SD) was 13.8 ± 10.6, and years of psychiatric clinical experience were 10.7 ± 9.5. The sample included 91 physicians (7.3%), 882 professional nurses (70.4%), 50 occupational therapists (4.0%), 37 psychiatric social workers (3.0%), 24 psychologists (1.9%), 24 pharmacists (1.9%), and 94 other occupations (7.5%). The professions of 50 subjects were unknown.
The NAS short form
The NAS measures nurses' EE and consists of three subscales (Hostility, Criticism and Positive Remarks). The top-four items that had greater factor loading among each subscale were chosen, and a total of 12 items were used in this study.
The Maslach Burnout Inventory
The Maslach Burnout Inventory (MBI) consists of 22 items that provide a measure of perceived burnout among staff.5 The instrument is composed of three subscales: Personal Accomplishment, Emotional Exhaustion, and Depersonalization. A Japanese version of the MBI has been validated by Masuko et al.6
Statistical analysis was performed using SPSS 14.0 for Windows (SPSS Inc, Chicago, IL, USA) at Nagoya City University. Pearson's correlation coefficient was used to examine the relationship between the NAS short form and the MBI. The method of factor analysis was principal axis factoring with varimax rotation.
Data for factor analysis were from 1252 psychiatric clinical staff members. A three factor model was chosen, which lists three interpretable factors that accounted for 61.4% of the variance.
Hostility, the first factor in the analysis, accounted for 34.1% of variance, and consisted of five items. However, one item was not included in Hostility because the difference between the factor loading of this item and the second highest loading factor was less than 0.1. Therefore, four items were chosen as the subscale of Hostility: I shout at him, I lose my temper with him, He is infuriating, and I argue with him. Criticism, the second factor, accounted for 16.7% of variance, and consisted of three items: I feel very frustrated with him, I feel disappointed with him, and I wish he would leave me alone. The third factor, Positive Remarks, accounted for 10.6% of variance and consisted of four items: He is easy to get along with, I feel very close to him, He appreciates what I do for him, and He tries to get alone with me.
The mean score (±SD) on the subscales of NAS short form were 8.7 ± 3.6 for Hostility, 11.8 ± 2.5 for Criticism, and 13.4 ± 2.2 for Positive Remarks. A significant difference in the subscale of NAS short form scores in a t-test was not observed between men and women.
Cronbach's α coefficient for Hostility, Criticism and Positive Remarks were 0.852, 0.846 and 0.645, respectively.
Pearson's correlation coefficient was used to examine the concurrent validity. All outcomes were statistically significant (P < 0.001). Hostility and Criticism in the NAS short form were positively correlated with Emotional Exhaustion (r = 0.22 for Hostility, 0.43 for Criticism) and Depersonalization (r = 0.35 for Hostility, 0.41 for Criticism) in the MBI, and were inversely correlated with Personal Accomplishment (r =−0.10 for Hostility, −0.19 for Criticism) in the MBI. Positive Remarks in the NAS short form were positively correlated with Personal Accomplishment (r = 0.40) in the MBI, and inversely correlated with Emotional Exhaustion (r =−0.11) and Depersonalization (r =−0.13) in the MBI.
In the present study, we developed the NAS short form and evaluated its reliability and validity for assessing clinical staff's EE more simply in psychiatric settings in Japan. In a factor analysis of the NAS short form, three factors were extracted and defined as individual subscales of Hostility, Criticism, and Positive Remarks. Cronbach's α was 0.8 or higher for Hostility and Criticism, although it was somewhat lower for Positive Remarks. In a previous study on the 30-item NAS,3 Cronbach's α was 0.845 for Hostility, 0.848 for Criticism, and 0.685 for Positive Remarks, showing that Cronbach's α for Positive Remarks was also relatively low.
Moreover, there was a significant correlation between individual subscales in the NAS short form and corresponding subscale in the MBI. Criticism and Hostility in the NAS short form represent a critical and negative attitude of clinical staff toward patients. Criticism and Hostility were significantly and positively correlated with Emotional Exhaustion and Depersonalization in the MBI. Positive remarks in the NAS short form represent an affirmative emotional attitude. Positive remarks were significantly and positively correlated with Personal Accomplishment. This suggests construct validity of the scale.
In conclusion, a short form of the NAS with acceptable validity and reliability was developed. This ques tionnaire may contribute to further research related to emotional attitudes of clinical staff in Japanese psychiatric settings.
This study, as a part of ‘The Treatment and the Support of Social Recovery for Schizophrenia by the Medical Network of Psychiatric Policy’, was supported by the Research Grant for Nervous and Mental Disorders from the Ministry of Health, Labor and Welfare, Japan in 2004.