Article Text

Original research
Validity and reliability of Psychiatric Nurse Self-Efficacy Scales: cross-sectional study
  1. Hironori Yada1,
  2. Ryo Odachi2,
  3. Keiichiro Adachi3,
  4. Hiroshi Abe4,
  5. Fukiyo Yonemoto1,
  6. Toshiya Fujiki5,
  7. Mika Fujii6,
  8. Takahiko Katoh7
  1. 1Department of Nursing, Faculty of Fukuoka Medical Technology, Teikyo University, Omuta, Fukuoka, Japan
  2. 2Division of Health Sciences, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
  3. 3Department of Fundamental Nursing, Yamaguchi University, Graduate School of Medicine, Ube, Yamaguchi, Japan
  4. 4Department of Clinical Psychology, Health Sciences University of Hokkaido, Ishikari-gun, Hokkaido, Japan
  5. 5Kumamoto Seimei Hospital, Chuo-ku, Kumamoto, Japan
  6. 6Sakuragaoka Hospital, Chuo-ku, Kumamoto, Japan
  7. 7Department of Public Health, Kumamoto University, Chuo-ku, Kumamoto, Japan
  1. Correspondence to Dr Hironori Yada; yada.hironori.jp{at}teikyo-u.ac.jp

Abstract

Objectives To develop the Psychiatric Nurse Self-Efficacy Scales, and to examine their reliability and validity.

Design We developed the Improved Self-Efficacy Scale (ISES) and Decreased Self-Efficacy Scale (DSES) using existing evidence. Statistical analysis was conducted on the data to test reliability and validity.

Setting The study’s setting was psychiatric facilities in three prefectures in Japan.

Participants Data from 514 valid responses were extracted of the 786 responses by psychiatric nurses.

Outcome measures The study measured the reliability and validity of the scales.

Results The ISES has two factors (‘Positive changes in the patient’ and ‘Prospect of continuing in psychiatric nursing’) and the DSES has three (‘Devaluation of own role as a psychiatric nurse’, ‘Decrease in nursing ability due to overload’ and ‘Difficulty in seeing any results in psychiatric nursing’). With regard to scale reliability, the Cronbach’s alpha coefficient was 0.634–0.845. With regard to scale validity, as the factorial validity of the ISES and DSES, for the ISES, χ2/df (110.625/37) ratio=2.990 (p<0.001), goodness-of-fit index (GFI)=0.962, adjusted GFI (AGFI)=0.932, comparative fit index (CFI)=0.967 and root mean square error of approximation (RMSEA)=0.062; for the DSES, χ2/df (101.982/37) ratio=2.756 (p<0.001), GFI=0.966, AGFI=0.940, CFI=0.943, RMSEA=0.059 and Akaike Information Criterion=159.982. The concurrent validity of the General Self-Efficacy Scale was r=0.149–0.446 (p<0.01) for ISES and r=−0.154 to −0.462 (p<0.01) for DSES, and the concurrent validity of the Stress Reaction Scale was r=−0.128 to 0.168 for ISES, r=0.214–0.398 for DSES (p<0.01).

Statistical analyses showed the scales to be reliable and valid measures.

Conclusions The ISES and DSES can accurately assess psychiatric nurses’ self-efficacy. Using these scales, it is possible to formulate programmes for improving psychiatric nurses’ feelings of self-efficacy.

  • mental health
  • occupational & industrial medicine
  • psychiatry
  • public health

Data availability statement

Data are available upon reasonable request. The data are free for reuse by all other researchers.

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Strengths and limitations of this study

  • The first useful scales that measured psychiatric nurses’ self-efficacy were developed in this study.

  • The content and language of the scale items were carefully selected by specialists.

  • Scale items were carefully selected by confirming the distribution and the discrimination power of item scores.

  • Scales have been verified for the reliability and validity.

  • The cross-validation and the test–retest reliability will be needed for future study.

Introduction

Bandura1 defined self-efficacy as ‘judgment of how well one can execute courses of action required to deal with prospective situations’ (p122); individuals with high self-efficacy set their own goals, while those with low self-efficacy may produce poor outcomes.2 Self-efficacy affects workers’ efforts and sustainability in learning difficult tasks.3 Self-efficacy may also partially buffer stress,4 and should not only be considered a part of mental healthcare but also as a factor to improve the quality of patient care. Therefore, maintaining self-efficacy has important implications for nurses.

Nursing is recognised as emotional labour.5 6 McVicar7 conducted a scoping review to assess the antecedents of nurses’ job stress and satisfaction. Nursing is perceived as a stressful occupation,8–10 with urgent mental health issues that need to be addressed.11 12 Mental health problems for nurses include conflict with other nursing staff, nursing role conflict, qualitative workload, quantitative workload and conflict with patients.13 Nurses working in general wards care for physical illness. The average length of stay in general wards, excluding psychiatry, is 16.1 days.14

While the average duration of hospitalisation for psychiatric patients in Japan is one of the longest worldwide—averaging 265.8 days—this has been decreasing in recent years.14 The Japanese government is now shifting the focus of psychiatric care from the hospital ward to the community, although it is difficult to know how quickly this change is being implemented. Psychiatric nurses need to respond to the drastically different working environment in psychiatric wards, compared with general wards; and given the situation-specific difficulties encountered by psychiatric nurses, such as communication difficulties related to mental issues and violence from psychiatric patients, the necessity of specialised mental healthcare for psychiatric nurses has been emphasised.15 At the same time, there is concern that psychiatric nurses exposed to such an environment may have reduced self-efficacy. Yada et al16 also highlighted the importance of self-efficacy when evaluating psychiatric nurses’ mental health. The factors associated with self-efficacy of psychiatric nurses were ‘Positive reactions by patients’, ‘Ability to positively change nurse–patient relationship’ and ‘Practicability of appropriate nursing’, and ‘Uncertainty in psychiatric nursing’ and ‘Nurses’ role loss’ represent the reality of psychiatric nurses.16

To improve the self-efficacy of psychiatric nurses, it first needs to be evaluated. Existing self-efficacy scales are inadequate, due to their lack of focus on the specific issues and environmental contexts encountered by psychiatric nurses. Many studies that evaluate the self-efficacy of healthcare professionals, including nurses, have been conducted using Sakano and Tohjoh’s17 General Self-Efficacy Scale (GSES).18 Bando et al19 devised a self-efficacy scale for psychiatric nurses that takes their relationships with their patients into consideration. However, self-efficacy scales for psychiatric nurses should include factors such as uncertainty and role loss and should not be limited to patient relationships.16 According to previous studies,16 20 there are multiple factors related to self-efficacy of psychiatric nurses, and it is necessary to develop a scale corresponding to these factors. Devising a comprehensive scale to evaluate the self-efficacy of psychiatric nurses, which is not found in the conventional GSES17 and patient-related self-efficacy scale,19 will facilitate the planning of specific mental healthcare interventions for psychiatric nurses. In Japan, there are about 82 000 full-time nurses working in psychiatric departments,21 and this cohort can be used for research that contributes to improving their quality of mental healthcare, thus improving patient care.

This study aimed to develop Psychiatric Nurse Self-Efficacy Scales (PNSS) to evaluate psychiatric nurses’ feelings of self-efficacy, which is difficult to grasp with existing scales, and to examine the reliability and validity of these developed scales.

Methods

Participants and procedure

The study adopted a cross-sectional survey design. The principal researcher requested the cooperation of 11 heads of nursing departments in psychiatric facilities in three prefectures. They gave written and verbal consent to distribute anonymous, self-administered questionnaires to nurses in their departments. A total of 514 valid responses with no missing values for scale scores were extracted from the 786 questionnaires completed by registered and associate nurses from January to March 2020. Participants provided written informed consent and were informed that they could freely withdraw from the survey. They did not receive any compensation or rewards. Each participant was given an envelope in which to seal their questionnaires to protect their privacy. Participation was anonymous, and only the researcher could access the data.

Patient and public involvement

No patients were involved with this study as it pertained to psychiatric nurses only.

Measures

Participant demographics

General demographic data (age, sex, job position, qualifications, years of experience as a nurse, experience working in a psychiatry department and nursing education level) were collected.

The PNSS

The initial PNSS included 52 items assessing factors related to self-efficacy, based on previously determined qualitative data on psychiatric nurses’ self-efficacy.20 Two researchers with experience in psychiatric nursing and two with experience as clinical psychologists reviewed the data and developed the question items. Forty-nine meaningful items from Yada et al20 were used to create the 52 items. The accuracy of item expression was discussed by four researchers—two psychology and two psychiatric nursing faculty members. Participants’ responses were rated on an 11-point scale from 0 (not at all) to 10 (yes). The initial PNSS comprised the Improved Self-Efficacy Scale (ISES; 26 items) and Decreased Self-Efficacy Scale (DSES; 26 items),

The ISES and DSES items were separately created based on linguistic data extracted using qualitative research.20 The ISES examines what improves self-efficacy, and the DSES investigates what reduces self-efficacy. The items between the two scales are completely different. Therefore, the ISES and DSES were separately analysed. The higher the score for the ISES, the higher the self-efficacy; and the higher the score for the DSES, the lower the self-efficacy.

The GSES

The GSES was used to assess concurrent validity; its reliability and validity have been established.17 It comprises 16 items rated on a 2-point scale, 0 (no) and 1 (yes); higher scores indicate higher self-efficacy. Cronbach’s alpha coefficient was 0.849. Permission to use the GSES was obtained from Cocolonet Co.

The Stress Reaction Scale

Self-efficacy reduces stress conditions.4 The Stress Reaction Scale (SRS) in the Brief Job Stress Questionnaire Short Version was used to assess the convergent validity of the PNSS; its reliability and validity were previously established.22 The SRS evaluates psychological stress and physical stress reactions and comprises 11 items rated on a 4-point Likert scale ranging from 0 (not at all) to 3 (definitely); higher scores indicate stronger stress reactions. Cronbach’s alpha coefficient in this study was 0.929. Permission to use the SRS was obtained from the Japanese Ministry of Health, Labour and Welfare.

Statistical analyses

Means, SDs, frequencies (n) and percentages (%) were calculated for participants’ demographic characteristics. For item analyses, the difficulty of the question item was confirmed by observing the number of missing values. Kurtosis, skewness, ceiling effect and floor effect were confirmed by observing their distribution on the 52 items (26 ISES item scores and 26 DSES item scores) in the initial version of the PNSS.

Item discrimination was confirmed by analysis of variance(ANOVA) (low, middle and high group) as a good–poor (G–P) analysis. The PNSS factor structure was identified using exploratory factor analysis (EFA). For reliability, the internal consistency of the factors was calculated using Cronbach’s alpha coefficient. Factor structure validity was confirmed by confirmatory factor analysis (CFA). The following values are considered good for each good index: χ2/df ratio from 2.0 to 3.0, goodness-of-fit index (GFI) >0.90, adjusted GFI (AGFI) >0.85, comparative fit index (CFI) >0.95 and root mean square error of approximation (RMSEA) <0.08.23 For concurrent and convergent validity, Pearson’s correlation coefficients were calculated to confirm correlation between the PNSS and the GSES and SRS factor structures. The significance level was set at p<0.05.

The evaluation score was developed by ±SD. Concretely, −1.5 SD≥ is low, −0.5 SD> to −1.5 SD< is low tendency, −0.5 SD ≤ to 0.5 SD≥ is normal, 0.5 SD< to 1.5 SD> is high tendency, and 1.5 SD≤ is high. Evolution scores were set for each scale and subscale score. The normal curve SD estimates include 38.2% of the data in the ±0.5 SD range and 86.6% of the data in the ±1.5 SD range.24

IBM SPSS V.24.0 for Windows was used for the item analysis, EFA, calculation of reliability, and calculation of convergent and predictive validity. IBM AMOS V.24.0 for Windows was used for the CFA.

Sample size

The main analysis used was factor analysis. If communalities are low, and there are a larger number of factors (more than 3 or 4), a sample size of more than 500 is likely to be required.25 We required a sample size of over 500, and our sample met that requirement with 514 valid responses.

Results

Demographics

Responses were received from 688 participants (recovery rate=87.53%). Among the respondents, 581 participants gave their informed consent to the investigation. The numbers of missing values for ISES and DSES of the 583 participants who agreed were 1–7, and it was judged that there were no items that were difficult to answer. There were four participants with large missing data that were presumed to be page oversight, and missing values were excluded. Valid respondents were 514 with no missing values in the scale item score (effective response rate=74.70%). Table 1 shows participant demographics.

Table 1

Participant demographics (N=514)

Item analysis

Kurtosis and skewness were not detected within ±2 in the 52-item distribution of scores.26 Discriminations for the 52 items were confirmed by a G–P analysis and all items were significant. Item discrimination was confirmed for all items. No ceiling or floor effect was detected within ±1 SD in the 52-item distribution of scores.

Factor structure of the PNSS

Items with communality less than 0.2 were excluded from subsequent analysis.27 The factor structure of the PNSS was identified using EFA. In the process of conducting EFA, the Kaiser-Meyer-Olkin (KMO) measure of sampling adequacy was confirmed. The principal factor method was used in the extraction of factors and promax rotation was conducted. The scree test28 was used to decide the number of factors. A factor loading of more than 0.5, which is more factor related, was adopted.29 Items with a factor loading of less than 0.5 were excluded from subsequent analysis. Factor names were determined and discussed by four researchers—two psychology and two psychiatric nursing faculty members.

For the ISES, four items with less than communality 0.2 were excluded from EFA.27 The KMO measure of sampling adequacy was 0.911, showing that EFA was appropriate.30 Two factors with 11 items were extracted: (1) ‘Positive changes in the patient’ with six items, including items related to those changes as recognised by the nurse; (2) ‘Prospect of continuing in psychiatric nursing’ with five items, including items related to experiences of failure and trust and the ability to persevere with nursing.

For the DSES, five items with communality less than 0.2 were excluded from EFA.27 The KMO measure of sampling adequacy was 0.865, showing that EFA was appropriate.30 Three factors with 11 items were extracted: (1) ‘Devaluation of own role as a psychiatric nurse’ with three items, including items that made nurses feel underappreciated; (2) ‘Decrease in nursing ability due to overload’ with four items, including items related to the deterioration of nursing ability in various situations; (3) ‘Difficulty in seeing any results in psychiatric nursing’ with four items, including items that make nurses feel their interventions have little effect on patients.

Tables 2 and 3 show the EFA results; Japanese–English translation–reverse translation was performed by translators, and agreement between languages confirmed (online supplemental file).

Table 2

The factor structure for improved self-efficacy among psychiatric nurses

Table 3

The factor structure for decreased self-efficacy among psychiatric nurses

Reliability of the PNSS

To determine the ISES and DSES reliability, we calculated Cronbach’s alpha coefficient for each scale and subscale (tables 2 and 3). Cronbach’s alpha coefficient was 0.839 for ‘Positive changes in the patient’, 0.809 for ‘Prospect of continuing in psychiatric nursing’, 0.845 for the overall ISES, 0.655 for ‘Devaluation of own role as a psychiatric nurse’, 0.634 for ‘Decrease in nursing ability due to overload’, 0.737 for ‘Difficulty in seeing any results in psychiatric nursing’, and 0.749 for the overall DSES.

Validity of the PNSS

For factorial validity, the compatibility of the extracted factors was analysed by CFA. For the ISES, the results followed the goodness-of-fit model: χ2/df (292.87/43) ratio=6.81 (p<0.01), GFI=0.897, AGFI=0.842, CFI=0.888, RMSEA=0.106 and Akaike Information Criterion (AIC)=338.87. The goodness of fit was not high; therefore, we assumed there were correlations among error variables in a factor, based on the modification index, and developed a revised model to fit the data. The error variable is an item-specific variable obtained by removing the influence of the factor from the observed variable. Paths were created between error variables as moderate positive correlations between e33 and e35, weak positive correlations between e29 and e31, e29 and e41, and e1 and e7; weak negative correlations between e31 and e35, and e27 and e41, yielding the following results: χ2/df (110.625/37) ratio=2.990 (p<0.001), GFI=0.962, AGFI=0.932, CFI=0.967, RMSEA=0.062 and AIC=168.625 (figure 1).

Figure 1

Fit indices of the proposed models for the Improved Self-Efficacy Scale (ISES). The ISES was found to fit a two-factor structure with 11 items. χ2/df (110.625/37, p<0.001): 2.990; goodness-of-fit index: 0.962; adjusted goodness-of-fit index: 0.932; comparative fit index: 0.967; root mean square error of approximation: 0.062; Akaike Information Criterion: 168.625.

For the DSES, the results followed the goodness-of-fit model: χ2/df (181.369/41) ratio=4.424 (p<0.001), GFI=0.942, AGFI=0.906, CFI=0.876, RMSEA=0.082, AIC=231.369. The goodness of fit was not high, therefore, we assumed there were correlations among error variables in a factor, based on the modification index, and developed a revised model to fit the data. Paths were created between error variables as weak positive correlations between e44 and 46, e34 and e36, e28 and e30, and e14 and e12, yielding the following results: χ2/df (101.982/37) ratio=2.756 (p<0.001), GFI=0.966, AGFI=0.940, CFI=0.943, RMSEA=0.059 and AIC=159.982 (figure 2).

Figure 2

Fit indices of the proposed models for the Decreased Self-Efficacy Scale (DSES). The DSES was found to fit a three-factor structure with 12 items. χ2/df(101.982/37, p<0.001): 2.756; goodness-of-fit index: 0.966; adjusted goodness-of-fit index: 0.940; comparative fit index: 0.943; root mean square error of approximation: 0.059; Akaike Information Criterion: 159.982.

To determine the concurrent and convergent validity of the ISES and DSES, the correlation coefficient with external variables was calculated for each scale and subscale score. In consideration of the concurrent validity, the GSES was used as an external variable. The correlation coefficient ranged from 0.149 to 0.446 (p<0.001) between the ISES and each ISES subscale score and the GSES score, indicating a weak–medium correlation. The correlation coefficient ranged from −0.154 to −0.462 between the DSES and each DSES subscale score and the GSES score, indicating a weak–medium correlation. In consideration of the convergent validity, the SRS was used as an external variable. The correlation coefficient ranged from −0.128 to −0.161 (p<0.001) between the ISES and each ISES subscale score and the SRS score, indicating a weak correlation. The correlation coefficient ranged from 0.214 to 0.398 between the DSES and each DSES subscale score and the SRS score, indicating a weak correlation. Table 4 shows the results of concurrent and convergent validities.

Table 4

The PNSS and the GSES, the SRS and the intention to continue working correlations

Discussion

This study examined the development and usefulness of a scale to evaluate psychiatric nurses’ self-efficacy comprehensively. The ISES has two factors (‘Positive changes in the patient’ and ‘Prospect of continuing in psychiatric nursing’) and the DSES has three (‘Decrease in nursing ability due to overload’, ‘Devaluation of own role as a psychiatric nurse’ and ‘Difficulty in seeing any results in psychiatric nursing’). Statistical analyses showed the scales to be valid measures. The following is a discussion of the results.

Participants’ characteristics

The distribution of age, years of psychiatric experience and job title seemed to be roughly the same, but the proportion of men in this study was higher than that in a previous study.31 The ratio of the education level of the study participants also seemed to be in rough agreement with a previous study.16

ISES analysis

The factor ‘Positive changes in the patient’ was similar to that of ‘Positive reaction of patients’, one of the factors of self-efficacy revealed in Yada et al’s16 study. Patience is required to treat psychiatric symptoms. Drug therapy and psychotherapy are less effective for treating the negative symptoms of schizophrenia, and long-term interventions by skilled specialists are required for this purpose.32 In such situations, psychiatric nurses may experience improved self-efficacy, when they see positive changes in the patient.

The factor ‘Prospect of continuing in psychiatric nursing’ was found to have a different meaning than that revealed in a previous study.16 According to critics of psychiatry, psychiatric diagnoses lack objectivity.33 Psychiatric nurses need to predict the condition from the patient’s behaviour. This requires working together with their own experience and teams, which may improve self-efficacy when psychiatric nurses are able to see patient care.

DSES analysis

The factor ‘Devaluation of own role as a psychiatric nurse’ was similar to ‘Nurse’s loss of role’.16 In psychiatry, the sense of distance from the patient varies from person to person, and it is difficult to obtain an appropriate distance in patient care.20 If the psychiatric nurse does not keep the proper distance from the patient, the patient may rely on other reliable nurses, and the psychiatric nurse may feel role loss and reduce self-efficacy.20

The factor ‘Decrease in nursing ability due to overload’ was found to have a different meaning to that found in a previous study.16 The responsibilities of psychiatric nurses include not just patient care but also lots of administrative work. One survey of psychiatric nurses found that 2.18 min was spent on symptom management, while 2 hours was spent on the related paperwork, and nurses who spent more time on direct patient care were more satisfied.34 When psychiatric nurses are unable to spend enough time on patient care, they may feel that they are not providing sufficient care, which may lead to reduced feelings of self-efficacy. In addition, one-third of patients admitted to Japan’s psychiatric wards in 2017 were 75 years and over.35 Older people often experience two or more chronic illnesses.36 Ageing increases the risk of dementia. Most dementias require care in daily life, and dealing with behavioural and psychological symptoms of dementia is also a problem as a symptom of dementia in psychiatry.37 Moreover, about half of Japanese psychiatric home-visiting nurses experience violence from their patients, especially verbal violence, and some nurses are at risk of post-traumatic stress disorder.38 According to previous research, when commissioned welfare volunteers feel threatened by people with mental health problems, it can lead to a deterioration of social distance between commissioned welfare volunteers and people with mental health problems.39 Similarly, when psychiatric nurses experience patient violence, they may feel threatened and unable to care for the patient any longer, which can lead to a feeling of decreased self-efficacy due to the loss of their role. Thus, as psychiatric nurses are burdened with ageing and violence in their patient, it may result in reduced self-efficacy.

The factor ‘Difficulty in seeing any results in psychiatric nursing’ was similar to ‘Uncertainty about psychiatric nursing’.16 As discussed, the average length of stay for Japanese psychiatric patients is much longer than in other countries,14 and deinstitutionalisation is evolving slowly. Psychiatric nurses, even with hard care, may not see the patient’s condition improve and be discharged. Psychiatric nurses may feel they do not achieve any results from their care and thus experience feelings of lower self-efficacy.

Reliability and validity of scales

To prove the reliability of subscales and scales, Cronbach’s alpha should exceed 0.60, and scores greater than 0.95 indicate redundancy.40 A previous study indicated that ‘an alpha coefficient of 0.70 has often been regarded as an acceptable threshold for reliability; however, 0.80 or 0.95 is preferred for the psychometric quality of scales’.41 The internal consistencies of some subscale may not be unacceptable, but not enough. As mentioned above, some of the factor structures related to the self-efficacy of psychiatric nurses in our previous study16 were similar to those in this study. However, unlike the current findings, most of the previous studies reported high internal consistencies. Therefore, this decrease in Cronbach’s alpha coefficient may be due to sample differences, and thus, future research is needed.

The factorial validity and GFIs were confirmed for ISES and DSES. Each value of the revised model for the ISES and the DSES exceeded indices,23 indicating acceptable goodness of fit. For convergent and predictive validity, the ISES and the DSES showed a weak–medium significant correlation between the GSES and the SRS. The ISES and the DSES were judged to be measures that can evaluate self-efficacy and associated stress.

The future of psychiatric nurses’ mental health

The ISES factors ‘Positive changes in the patient’ and ‘Prospect of continuing in psychiatric nursing’, and the DSES factors ‘Decrease in nursing ability due to overload’, ‘Devaluation of own role as a psychiatric nurse’, and ‘Difficulty in seeing any results in psychiatric nursing’ were developed in the current study. Self-efficacy is recovered through resilience,42 so it was necessary to confirm how resilience can control ‘Positive changes in the patient’, ‘Prospect of continuing in psychiatric nursing’, ‘Decrease in nursing ability due to overload’, ‘Devaluation of own role as a psychiatric nurse’ and ‘Difficulty in seeing any results in psychiatric nursing’ for psychiatric nurses’ future mental healthcare.

Future avenues for this research

The scales of this study have aspects of improving and decreasing self-efficacy of psychiatric nurses, and each scale has multiple subscales. Therefore, it is possible to grasp the self-efficacy from multiple aspects. In the future, multifaceted intervention in the self-efficacy of psychiatric nurses will be possible. However, this scale requires further examination for reliability and validity among different samples to determine its cross-validation and predictive validity. Moreover, future studies are also needed to validate the test–retest reliability.

Study limitations

Some limitations of the present study are that there were more male participants than in previous studies, which may be due to selection bias. A method such as non-probability sampling is required as a sample extraction method. In addition, the standard scores were calculated from the data of this study, so the results are not absolute indices; follow-up studies are required.

Conclusions

In this study, the ISES factors ‘Positive changes in the patient’ and ‘Prospect of continuing in psychiatric nursing’, and the DSES factors ‘Decrease in nursing ability due to overload’, ‘Devaluation of own role as a psychiatric nurse’, and ‘Difficulty in seeing any results in psychiatric nursing’ were developed for the PNSS. Reliability and validity analyses indicated that the ISES and the DSES are useful. Using these scales, it is possible to formulate programmes for improving psychiatric nurses’ feelings of self-efficacy.

Interventions to increase resilience are useful for improving their positive feelings of self-efficacy and preventing feelings of decreased self-efficacy. It is necessary to confirm how resilience can control ‘Positive changes in the patient’, ‘Prospect of continuing in psychiatric nursing’, ‘Decrease in nursing ability due to overload’, ‘Devaluation of own role as a psychiatric nurse’ and ‘Difficulty in seeing any results in psychiatric nursing’ for mental healthcare planning. When measuring the self-efficacy of psychiatric nurses in intervention studies, scales should be used to indicate directions for effective mental healthcare. Interventions to increase the resilience of psychiatric nurses are useful for improving self-efficacy and preventing feelings of decreased self-efficacy. Improved psychiatric nurse self-efficacy will have positive consequences for patient care.

Data availability statement

Data are available upon reasonable request. The data are free for reuse by all other researchers.

Ethics statements

Patient consent for publication

Ethics approval

This study involves human participants and was approved by the Ethics Review Board of Yamaguchi University Graduate School of Medicine, School of Health Sciences (approval no. 605-2). Participants gave informed consent to participate in the study before taking part.

Acknowledgments

The authors extend their thanks to the psychiatric nurses who participated in this research, to Editage (www.editage.jp) for English-language editing, and Ulatus (https://www.ulatus.com/) for Japanese–English translation–reverse translation of the questionnaire instruments. Finally, they thank Miss Asako Kiyonaga of Yamaguchi University for cooperating in recruiting research subjects.

References

Supplementary materials

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Footnotes

  • Contributors HY, RO, KA and HA were involved in study design. HY obtained funding. HY, TF, MF and TK took part in the investigation. HY, RO, KA, HA, FY, TF, MF and TK were involved in data analysis and interpretation. All authors critically revised the report, commented on drafts of the manuscript and approved the final manuscript. HY accepts full responsibility for the work and/or the conduct of the study, had access to the data, and controlled the decision to publish.

  • Funding This work was supported by JSPS KAKENHI (grant number JP 19K19498).

  • Competing interests None declared.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.