A Second-Order Confirmatory Factor Analysis of the Moral Distress Scale-Revised for Nurses

Abstract

Background:

Moral distress is a growing problem for healthcare professionals that may lead to dissatisfaction, resignation, or occupational burnout if left unattended, and nurses experience different levels of this phenomenon.

Objectives:

This study aims to investigate the factor structure of the Persian version of the Moral Distress Scale–Revised in intensive care and general nurses.

Research design:

This methodological research was conducted with 771 nurses from eight hospitals in the Mazandaran Province of Iran in 2017. Participants completed the Moral Distress Scale–Revised, data collected, and factor structure assessed using the construct, convergent, and divergent validity methods. The reliability of the scale was assessed using internal consistency (Cronbach’s alpha, Theta, and McDonald’s omega coefficients) and construct reliability.

Ethical considerations:

This study was approved by the Ethics Committee of Mazandaran University of Medical Sciences.

Findings:

The exploratory factor analysis (N = 380) showed that the Moral Distress Scale–Revised has five factors: lack of professional competence at work, ignoring ethical issues and patient conditions, futile care, carrying out the physician’s orders without question and unsafe care, and providing care under personal and organizational pressures, which explained 56.62% of the overall variance. The confirmatory factor analysis (N = 391) supported the five-factor solution and the second-order latent factor model. The first-order model did not show a favorable convergent and divergent validity. Ultimately, the Moral Distress Scale–Revised was found to have a favorable internal consistency and construct reliability.

Discussion and conclusion:

The Moral Distress Scale–Revised was found to be a multidimensional construct. The data obtained confirmed the hypothesis of the factor structure model with a latent second-order variable. Since the convergent and divergent validity of the scale were not confirmed in this study, further assessment is necessary in future studies.

Keywords

Factor analysis moral distress nurses psychometric reliability validity

Introduction

Moral distress is defined as painful feelings or psychological disequilibrium^1,2 that occurs when an individual is aware of, but unable to take, the morally right course of action. This may be due to organizational obstacles such as time constraints, a lack of support from the authorities, or conflict with colleagues.^1
–3 The rapid development of medical technologies and testing has posed more complex ethical issues for nurses and clinicians than in past decades. Clinical training in professional ethics has become important for nursing students and graduates as the profession is frequently faced with ethical issues, often on a day-to-day basis. As a consequence, nurses commonly report feelings of moral distress, and empirical research has found that such feelings are associated with mental health concerns.⁴

Moral distress is a major problem that not only threatens the occupational satisfaction of nurses but also their ability to perform their typical duties and responsibilities.^5
–7 Moral distress has been found to cause physical, mental, social, and professional problems in nurses^8,9 and is reported to impact employee retention, job satisfaction, and the quality of patient care.^1
–3 Consequently, these issues can lead to increased medical errors, resignation, feeling powerless, and compassion fatigue.¹⁰

While patient care, in general, is commonly associated with moral dilemmas and ethical issues,^3,5,11 nurses, compared with other medical professionals, such as doctors, tend to spend greater amounts of time with patients due to the nature of their work.^7,12 Nurses may find themselves in roles that are outside the technical aspects of nursing or their expected professional boundaries. They may be asked for advice or guidance on issues that are in conflict with their own belief systems (e.g. reproductive health or organ and tissue donation) or that are outside their own professional expertise and competencies. Issues may also arise when nurses have dual relationships with patients. Such ethical dilemmas can potentially cause multiple issues and expose nurses to moral conflicts that lack clear resolutions.⁹

Occupational and organizational conditions also expose nurses to a variety of stressors that may also pose various moral conundrums.^2,13,14 Nurses are required to make quick clinical decisions about patient care and needs while often facing organizational barriers and pressures such as heavy workloads, staff shortages, or lack of medical equipment.¹¹ Nurses’ perceptions of moral distress can be influenced by their working conditions. For instance, issues such as limited opportunities for promotion, the lack of rewards or incentives, improper interactions with medical colleagues, and dissatisfaction with insufficient time for patient care may increase the experience of stress for nurses.^{10,12,15
–17} Furthermore, communication problems, ineffective actions, medical care errors, the improper assignment of responsibilities, and a lack of resources, and/or competencies are some other factors that can cause moral distress in nurses.^14,18,19 Research indicates that the degree of experiencing moral distress in nurses varies with sex,¹¹ social values and culture, and managerial policies and rules.^10,19
–21

Corley was the first to develop a Moral Distress Scale (MDS) to measure moral distress in nurses.^1
–3 Although this scale has been widely used to measure moral distress in nurses, in a clinical context, its administration has been found to be time-consuming and, therefore, its application in research contexts rather difficult.^2,22 Responding to these concerns, Hamric et al.² revised the scale, reducing the measure to 21 items. The factor structure of the Moral Distress Scale–Revised (MDS-R) has been assessed in different countries and varying results have been reported. The MDS-R has been used across different disciplines and healthcare settings and was first used with ICU nurses and physicians at a teaching hospital in Southeastern United States, where the data obtained identified a one-factor structure.² The tool also showed a one-factor structure in a study with ICU nurses in Turkey.²¹ In contrast to these findings, Chae et al.²³ in South Korea and Soleimani et al.²² in Iran found five-factor structures for the tool in different hospital wards. Moral distress and its related outcomes may therefore depend on the cultural context.^15,19

Considering the effect of moral distress on job satisfaction for nurses, the impact on patient care, and the cultural sensitivity of the construct,^10,19
–21 research is needed to investigate the factor structure of the MDS-R² within a Persian context. This study was therefore conducted to investigate and determine the factor structure of the Persian version of the MDS-R in nurses.

Methods

Participants and setting

This cross-sectional methodological study was conducted over 4 months from January to April 2017. A total of 771 nurses with more than 1 year of work experience were selected using the stratified random sampling of eight hospitals in Mazandaran Province of Iran.

Instruments

Data were collected through paper-and-pencil questionnaires completed by nurses in clinical units. The MDS-R² contains 21 items. Each item is scored based on the respondent’s perception of a given situation based on a five-point Likert scale. A lower composite score indicates less moral distress and a higher composite score indicates more moral distress.

Construct validity assessment

Construct validity was assessed using the exploratory factor analysis (EFA; N = 380) and confirmatory factor analysis (CFA; N = 391). The Kaiser–Meyer–Olkin (KMO) Index and Bartlett’s Test of Sphericity were used to assess sampling adequacy; KMO > 0.8 denoted an adequate sample.²⁴ The latent factors of the EFA were extracted by maximum likelihood using Promax rotation and a screen plot. The presence of an item in a factor was determined as approximately 0.2 using the equation CV = 5.152÷√(n − 2), where CV = the number of extractable factors and n = sample size.²⁵ According to the three-indicator rule, there must be at least three items for each latent variable in the EFA.²⁴ Items with communalities less than 0.5 were excluded from the EFA.

The factors extracted using the first- and second-order factor analysis and the most common goodness-of-fit indices of the proposed model were assessed based on the threshold of acceptance by finding the maximum likelihood. There are no golden rules for evaluating goodness-of-fit; however, it is necessary to report a variety of indices because different indices often reflect a different features of the model.²⁶ Fit indices employed in the study included Chi-square (χ²), Chi-square/degree-of-freedom ratio (normalized Chi-square CMIN/DF), Adjusted Goodness-of-Fit Index (AGFI) > 0.8, Parsimonious Comparative Fit Index (PCFI) > 0.50, Comparative Fit Index (CFI) > 0.90, Incremental Fit Index (IFI) > 0.90, Parsimonious Normed Fit Index (PNFI) > 0.50, Root Mean Square Error of Approximation (RMSEA) < 0.05 good.²⁵

In the second-order factor analysis, it was assumed that the extracted latent variables in the first stage were present. Thus, the second-order factor analysis represented the more general concepts at secondary and upper levels.²⁷

Convergent and divergent validity

The convergent and divergent validity of the MDS-R was assessed using the average variance extracted (AVE), the maximum shared squared variance (MSV), and the average shared squared variance (ASV). The convergent validity is established when AVE > 0.5 and divergent validity is established when both MSV < AVE and ASV < AVE.²⁸

Reliability

To assess the internal consistency of the scale, coefficients of Cronbach’s alpha, McDonald Omega, and Theta were estimated and values higher than 0.7 were considered acceptable.²⁹ The construct reliability, which replaces Cronbach’s alpha coefficient in structural equation modeling, was then assessed, and construct reliability greater than 0.7 were considered acceptable.³⁰

Normality and outliers

The normal distribution of the data, the outliers, and missing data were separately assessed. The presence of multivariate outliers was assessed using the Mahalanobis d-squared method (p < 0.001) and the violation of multivariate kurtosis using the Mardia coefficient (>8).³¹ The number of missing data was assessed using multiple imputation analysis, which was then replaced with participants’ mean responses.

Ethical considerations

This research was approved by the ethics committee of Mazandaran University of Medical Sciences (Code: 978). Prior to beginning the study, nurses were briefed on the study objectives prior to providing their informed consent for participation. All participants were ensured confidentiality of their data.

Results

A total of 771 nurses participated in this study who were comprised of 165 males (21.4%) and 606 females (78.6%), who had an age range of 22–62 years and reported work experience to be between 1 and 32 years (Table 1). The sampling adequacy (KMO) was calculated as 0.915 and Bartlett’s test was calculated as χ² = 5030.72, df = 190 (p < 0.001). The EFA resulted in the extraction of five factors (lack of professional competence at work, ignoring ethical issues and patient conditions, futile care, carrying out the physician’s orders without question and unsafe care, and providing care under personal and organizational pressures), which explained 56.62% of the total variance (Table 2).

Table 1.

Socio-demographic and clinical profiles of the participants (n = 771).

Variable		Number (%)
Sex	Male	165 (21.4)
Sex	Female	606 (78.6)
Educational level	Diploma, nursing	18 (23)
	BS	665 (86.3)
	MS	88 (11.4)
Marital status	Single	179 (23.2)
	Married	579 (75.1)
	Widowed	6 (0.8)
	Divorced	7 (0.9)
Place of living	City	650 (84.3)
Place of living	Village	121 (15.7)
Clinical Unit	General	371 (48.1)
Clinical Unit	Critical care	400 (51.9)
Age: mean (SD), years Work experience: mean (SD), years		34.5 (6.68) 10.26 (5.96)

SD: standard deviation.

Table 2.

Exploratory factor analysis of Persian version of the Moral Distress Scale–Revised in nurses.

Factors	Items	Factor loading	h2	Eigenvalue	% of variance
1	Q20. Watch patient care suffer because of a lack of provider continuity.	0.742	0.678	2.887	13.747
	Q18. Witness diminished patient care quality due to poor team communication.	0.721	0.607
	Q17. Work with nurses or other healthcare providers who are not as competent as the patient care requires.	0.657	0.661
	Q21. Work with levels of nurse or other care provider staffing that I consider unsafe.	0.619	0.516
	Q19. Ignore situations in which patients have not been given adequate information to insure informed consent.	0.565	0.583
2	Q14. Increase the dose of sedatives/opiates for an unconscious patient that I believe could hasten the patient’s death.	0.732	0.662	2.689	12.803
	Q15. Take no action about an observed ethical issue because the involved staff member or someone in a position of authority requested that I do nothing.	0.718	0.648
	Q16. Follow the family’s wishes for the patient’s care when I do not agree with them, but do so because of fears of a lawsuit.	0.687	0.598
	Q8. Avoid taking action when I learn that a physician or nurse colleague has made a medical error and does not report it.	0.445	0.419
3	Q6. Carry out the physician’s orders for what I consider to be unnecessary tests and treatments.	0.761	0.627	2.334	11.114
	Q4. Initiate extensive life-saving actions when I think they only prolong death.	0.703	0.547
	Q7. Continue to participate in care for a hopelessly ill person who is being sustained on a ventilator, when no one will make a decision to withdraw support.	0.617	0.522
	Q9. Assist a physician who, in my opinion, is providing incompetent care.	0.449	0.495
4	Q11. Witness medical students perform painful procedures on patients solely to increase their skill.	0.666	0.589	2.165	10.307
	Q10. Be required to care for patients I don’t feel qualified to care for.	0.589	0.485
	Q13. Follow the physician’s request not to discuss the patient’s prognosis with the patient or family.	0.562	0.538
	Q12. Provide care that does not relieve the patient’s suffering because the physician fears that increasing the dose of pain medication will cause death.	0.528	0.537
	Q5. Follow the family’s request not to discuss death with a dying patient who asks about dying.	0.475	0.478
5	Q1. Provide less than optimal care due to pressures from administrators or insurers to reduce costs.	0.734	0.625	1.817	8.655
	Q2. Witness healthcare providers giving “false hope” to a patient or family.	0.656	0.566
	Q3. Follow the family’s wishes to continue life support even though I believe it is not in the best interest of the patient.	0.503	0.510

h2: communalities.

In the CFA, the results of the Chi-square test for goodness-of-fit were first obtained as χ² (172) = 680.24 (p < 0.001), and other indices were then assessed for the fit of the model. According to Table 3, all the indices (PCFI = 0.734, PNFI = 0.709, CMIN/DF = 3.955, RMSEA = 0.062, AGFI = 0.891, IFI = 0.920, and CFI = 0.911) confirmed a good fit of the final model. According to the final factor structure of the MDS-R, there were correlations between the measurement errors of items 1 and 4, 4 and 5, 6 and 7, 8 and 9, 10 and 11, 12 and 13, and 14 and 17 (Figure 1).

Table 3.

Fit indices of the first- and second-order confirmatory factor analysis of the MDS-R.

CFA	χ ²	df	p-value	CMIN/DF	RMSEA	PCFI	PNFI	AGFI	IFI	CFI
First-order after structure modification	628.64	175	<0.001	3.955	0.062	0.734	0.734	0.891	0.920	0.911
Second-order after structure modification	702.83	179	<0.001	3.926	0.062	0.770	0.746	0.896	0.940	0.930

MDS-R: Moral Distress Scale–Revised; CFA: confirmatory factor analysis; CMIN/DF: Chi-square/degree-of-freedom ratio; RMSEA: Root Mean Square Error of Approximation; PCFI: Parsimonious Comparative Fit Index; PNFI: Parsimonious Normed Fit Index; AGFI: Adjusted Goodness-of-Fit Index; IFI: Incremental Fit Index; CFI: Comparative Fit Index.

Fit indices: PNFI, PCFI, AGFI (>0.5), CFI, IFI (>0.9), RMSEA (>0.08), CMIN/DF (>3 good, >5 acceptable).

Figure 1.

Structure of MDS-R: modified model of first-order confirmation factor analysis.

Following the first-order CFA, a separate assessment of the factors of the MDS-R and the correlation between the constructs occurred. Subscales were determined using structural equations. The second-order factor analysis was performed to examine whether or not all the factors fitted the general concept of “moral distress.” Table 3 presents the indices of fit for the second-order CFA compared to the first-order model.

Figure 2 shows the structural model and the CFA of the MDS-R with standardized factor loadings. The factor loadings were greater than 0.3 for all the items and were significant at p < 0.05. As shown in Table 4, all five factors extracted had acceptable internal consistency (>0.7). Assessing the ASV, MSV, and AVE, however, showed that the MDS-R does not have a good convergent and divergent validity.

Figure 2.

Structure of MDS-R: modified model of second-order confirmation factor analysis.

Table 4.

Convergent and divergent validity, internal consistency, and constructs reliability of MDS-R.

Factor	α	θ	Ω	CR	AVE	MSV	ASV
Lack of competence in the work	0.823	0.817	0.823	0.821	0.607	0.780	0.472
Ignoring	0.806	0.837	0.790	0.769	0.637	0.800	0.490
Futile care	0.800	0.761	0.784	0.778	0.486	0.700	0.401
Absolute follow the physician’s orders and unsafe care	0.739	0.806	0.776	0.772	0.637	0.750	0.399
Providing care under personal and organizational pressures	0.894	0.707	0.808	0.748	0.564	0.650	0.351

MDS-R: Moral Distress Scale–Revised; α: Cronbach’s alpha coefficients; θ: theta coefficient; Ω: McDonald omega coefficient; CR: construct reliability; AVE: average variance extracted; MSV: maximum shared squared variance; ASV: average shared squared variance.

Discussion

This study was conducted to assess the factor structure of the Persian version of the 21-item MDS-R in nurses working at hospitals. The results revealed five subscales for the MDS-R: lack of professional competence at work, ignoring ethical issues and patient conditions, futile care, carrying out the physician’s orders without question and unsafe care, and providing care under personal and organizational pressures.

In support of these findings, Chae et al.²³ found five factors (e.g. futile care, nursing practice, the institutional and contextual factor, limits to claim the ethical issue, and physician practice) for the MDS-R for nurses in South Korean hospitals. In Iran, Soleimani et al.²² also found a five-factor structure (e.g. role of healthcare providers, futile care, obeying the doctor’s orders without question and working with unsafe colleagues, the unavailability of doctors in some areas of care, and the limitations of the organization) for the scale. Hamric et al.² and Karagozoglu et al.²¹ had only identified a one-factor structure for the MDS-R.

Corley et al.³ initially proposed three subscales for the MDS for intensive care nurses, which included: responsibility, disinterest for patient care, and deception. In a study conducted by Vaziri et al.¹ that aimed to develop and validate the MDS for use in Iranian nurses, three factors were obtained that included neglecting the patient, the patient’s decision-making power, and professional-functional competence. Mixed findings have also been reported in other countries. For example, in Brazil, the MDS was found to have four subscales (i.e. lack of competence, denying the role of the nurse as the patient’s supporter, treatment resistance, and disrespecting the patient’s independence).¹⁶ In Japan, the MDS for psychiatric nurses was presented with factors including unethical conduct by caregivers, low staffing, and acquiescence to patients’ rights violations.³² These studies very much suggest that the MDS, revised or not, is very sensitive to cultural context and country of use.

For this study, the first factor identified through EFA was “lack of professional competence at work.” Based on the items that comprised this factor, it appears that nurses’ experience of moral distress is influenced by working with incompetent doctors, nurses, or other care providers or more generally, poor teamwork. Past studies have supported this finding and have shown that staff shortages and a perception that colleagues are incompetent can influence higher moral distress in nurses.^16,21,32 When nurses are dissatisfied with the quality of care, they themselves provide, they are more likely to report increased moral distress, and reduce team collaboration and communication.¹³ Other research has shown that the quality of patient care decreases as moral distress and ethical challenges of nurses increase.³³

The second factor identified in this study was “Ignoring ethical issues and patient conditions.” Based on the items of this factor, nurses appear to experience moral distress when there is a violation of patients’ rights due to being required to follow doctors’ orders or the wishes of a patient’s family. Ignoring unethical practice or not reporting medical errors committed by the doctors or other colleagues was also related to this factor. In a similar study in Brazil, Barlem et al.¹⁶ found that disrespecting the patients’ independence leads to moral distress in nurses. The review of Iranian studies on the subject also shows that many nurses experience moderate to high levels of moral distress due to various variables that may also influence ignoring in the profession. For example, the influence of organizational hierarchies, the traditional work structure, power imbalances, the perceived overarching authority of doctors, and the disrespect for patients’ independence by other medical staff or family members of the patient.^1,5,7,9

The third factor identified in this study was “futile care.” Nurses appear to suffer the highest levels of distress when they are involved in ineffective patient care that prolongs the process of treatment and increases patient suffering. An example of this may be seen when a medical team cannot make a decision about a dying patient and there is an absence of care plan. Studies have shown that nurses experience the highest levels of moral distress when complying with a doctors’ orders, which they perceive as unnecessary.^16,34 In support of the current findings, Elpern et al.³⁵ found that ICU nurses experience moderate levels of moral distress, but suffer from the highest levels of distress when they have to perform invasive procedures on patients who are not expected to benefit. In Iran, ICU nurses experience high levels of moral distress, job dissatisfaction, and the desire to leave the profession when they have to perform futile care.¹⁸ In a qualitative study, Atashzadeh Shorideh et al.¹⁹ found that futile care can be the result of communication problems or staff simply ignoring possible injustices to patient to care.

The fourth factor identified was “carrying out the physician’s orders without question and unsafe care.” In this study, a nurse who follows a physician’s orders and performs duties without regard to moral obligations or who follows a family’s wishes at the risk of disrespecting the patients’ rights and dignity is more likely to perceive greater moral distress.

This study also found that nurses appear to experience moral distress when they witness the provision of inadequate care by novice students seeking to gain medical skills or when they are forced to perform care without having the necessary expertise. Silen et al.³⁶ found similar results, reporting that nurses experience high levels of moral distress when the patients do not receive proper and safe care. The last factor identified was “providing care under personal and organizational pressures.” Nurses appear to experience moral distress when they cannot provide ideal care to patients due to pressure from managers and organizational rules. For this study, such pressures include organizational constraints such as budgetary limitations in patient care or when a nurse has witnessed a member of the medical team giving false hope to patients and their families. Past studies have shown similar results and provide compelling evidence for the need of effective training and professional supervision of nurses to overcome the ethical challenges posed by personal and organizational barriers.^{1,5,9,12,16,32}

To find a more precise model of structural equations, the second-order CFA was also performed. This method seeks to obtain a more significant method of data collection while assuming that the latent variables in the common variance are due to one or more higher-order factors and that the intended scale has two orders.²⁷ A high correlation between the first-order constructs shows that the latent variables do not fully act as an independent variable and the correlation between them reflects the presence of a more general construct (moral distress) in a secondary conceptual level, where the best approach to the assessment of the structure is structural equation modeling, since it can identify the first-order constructs that were proposed as the latent variables.²⁸ Anderson and Gerbing³⁷ proposed that the intended construct must first be created through first-order factor analysis, and the good fit of the conceptual construct be then determined for the assessment of the structural equation model using second-order factor analysis.

The reliability of the MDS-R was assessed using different coefficients, and findings indicated the acceptable stability of the scale for a Persian context. The reliability of the MDS-R has been demonstrated in various studies through different ways. In the study conducted by Soleimani et al.,²² the reliability of the scale using Cronbach’s alpha coefficients was 0.853, 0.686, 0.685, and 0.711 for factors one to four, and in the study by Hamric et al.,² this coefficient was reported as 0.89, 0.67, and 0.88 for the nurses, the physicians and all the participants.

Karagozoglu et al.²¹ reported the reliability of the scale as 0.82 and 0.85 using the test–retest correlation coefficient and Cronbach’s alpha coefficient, respectively. Chae et al.²³ reported the reliability of the scale using Cronbach’s alpha as 0.91 and it is a Guttman split-half reliability as 0.83 for the total scale.

This study examines moral distress on the nursing profession. The experience of moral distress for nurses can create significant decreases in workplace satisfaction. Studies that have investigated attrition rates in the nursing profession have found that moral distress is often a precursor to site transfer requests or for nurses leaving the profession entirely.⁵ Borhani et al.¹² reported that, despite experiencing moral distress in the workplace, Iranian nurses are unable to leave their job due to the increasing cost of living and the lack of improved financial prospects in a related job. Nurses, therefore, are often forced to bear hardships associated with their work and stay in the profession.

Implications and limitations

This study had a number of limitations, including the use of the self-report method of data collection, which can entail errors in reporting. Also, since the study was conducted in a certain geographical region, generalizing the results to wider geographical areas should be pursued with care. Future research should consider in different geographical regions.

This study used an adequate sample size and the results can properly reflect the status of moral distress in nurses within a Persian context. Therefore, this study has demonstrated the usefulness of the MDS-R for nurses in Iran. The implications of this findings provide a reliable and valid tool for nurses to use in a practice or research context. Managers and lead clinicians should consider the implications of moral distress in their nursing staff and ensure that professional workplace interventions and strategies are in place to mitigate harm caused from the experience of this construct. All nursing staff should be provided the opportunity for ongoing training and professional development to facilitate effective ethical decision-making and mitigate harm caused from moral distress. Nurses should be encouraged to become members of professional bodies related to their expertise in order to access resources, guidance, and peer mentorship. Finally, organizations that employ nurses should ensure the provision of regular professional supervision for nurses so that ethical and professional issues can be managed and discussed effectively as they arise.

Conclusion

In sum, this findings suggest that, although the convergent and divergent validity of the first-order structure of the MDS-R was not confirmed, all the factors of the multidimensional scale were identified to support previous research that has examined moral distress in nurses.

Footnotes

Acknowledgements

The authors extend their sincere gratitude to the nurses who helped make this research possible.

Conflict of interest

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by the Mazandaran University of Medical Sciences, Iran.

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