Participant and study population
The analytical sample included 150 emergency department nurses with a mean age of 32.0 years (SD = 5.2). Ninety participants (60.0%) were men, and 60 (40.0%) were women. Fifty nurses (33.3%) had 1–5 years of ED experience, 60 (40.0%) had 6–10 years, and 40 (26.7%) had 11–15 years. Mean workload and trauma-exposure scores were toward the upper parts of their study-specific ranges, while coping, compassion satisfaction, and CF scores were near the middle of their respective ranges (Table 2).
Questionnaire outcome and the study variables correlations
Pairwise correlations are shown in Figure 3. CF was positively correlated with workload (r = 0.75) and trauma exposure (r = 0.62). Workload was also positively correlated with trauma exposure (r = 0.68). CF was inversely correlated with coping mechanisms (r = −0.52) and compassion satisfaction (r = −0.60), while coping mechanisms were positively correlated with compassion satisfaction (r = 0.60). All reported correlations had p < 0.001. These pairwise coefficients do not represent interactions, multivariable effects, or causation.
Data quality and preparation
Assumptions were met for the one-way ANOVA, with group-specific Shapiro-Wilk p-values ranging from 0.196 to 0.526 and Levene's test indicating homogeneity of variance, F (2,147) = 1.34, p = 0.266. Compassion fatigue differed across ED-experience groups, F (2,147) = 5.14, p = 0.007, eta-squared = 0.065, as shown in Table 3. Tukey HSD pairwise comparisons showed that the mean compassion-fatigue score was higher in the 11-15-year group than in the 1-5-year group (mean difference = 0.86, adjusted p = 0.005), whereas no other pairwise differences were significant. Compassion fatigue also differed across coping categories, χ2 (2) = 26.81, p < 0.001, η2 = 0.169. Dunn tests with Bonferroni adjustment showed lower compassion-fatigue scores in the high-coping group than in the low-coping group (adjusted p < 0.001) and the moderate-coping group (adjusted p < 0.001). In contrast, the low- and moderate-coping groups did not differ significantly (adjusted p = 0.668), as shown in Table 4 and Figure 4.
Descriptive and inferential results
Mean compassion fatigue was 4.72 among nurses with 1–5 years of ED experience, 5.09 among those with 6-10 years, and 5.58 among nurses with 11–15 years of ED experience, as shown in Figure 5. Workload and trauma-exposure scores increased across the experience groups, whereas coping scores were slightly lower in the most-experienced group, as shown in Table 5 and Figure 5. These descriptive values are based on the N = 150 analysis and do not indicate a causal effect.
Coping mechanisms and compassion fatigue
Mean compassion fatigue was highest in the low-coping group (5.71) and lowest in the high-coping group (4.24). Mean compassion-satisfaction scores were 4.00 in the low-coping group and 5.13 in the high-coping group (Table 6 and Figure 6). This pattern is consistent with an inverse relationship between adaptive coping and compassion fatigue; however, it does not provide evidence of an intervention effect.
Model Evaluation Results
The four-predictor multiple regression model, as shown in Table 7, was statistically significant (R2 = 0.856, adjusted R2 = 0.852; F (4, 145) = 215.16, p < 0.001). Workload showed the largest positive standardized association with compassion fatigue (β = 0.419), followed by trauma exposure (β = 0.323). Coping mechanisms (β = -0.247) and compassion satisfaction (β = -0.350) were negatively associated with compassion fatigue, as presented in Table 8 and Figure 7. Variance inflation factors ranged from 1.33 to 1.45, and tolerance values ranged from 0.69 to 0.75, indicating no serious multicollinearity. As shown in Table 7 and Figure 8, residual diagnostics were satisfactory: Shapiro-Wilk W = 0.983, p = 0.059; Breusch-Pagan p = 0.278; Durbin-Watson = 1.97; and maximum Cook's distance = 0.063.
Predictive model performance
As shown in Table 9 and Figure 9, Random Forest had the highest reported internal performance, with an accuracy of 85%, a precision of 82%, a recall of 80%, an F1-score of 81%, and an ROC-AUC of 0.84. Support Vector Machine achieved an accuracy of 83% and ROC-AUC of 0.83, while logistic regression achieved an accuracy of 80% and ROC-AUC of 0.80. The numerical differences were small and were not accompanied by confidence intervals, fold-level distributions, calibration, or external validation; therefore, they do not establish superiority of Random Forest in other hospitals or populations.
The reported standardized predictor strengths were workload (0.42), compassion satisfaction (0.33 in the inverse direction), trauma exposure (0.31), and coping mechanisms (0.28 in the inverse direction). This ordering agreed with the pairwise and adjusted analyses: workload and trauma exposure were risk-associated, while compassion satisfaction and coping mechanisms were protective-associated.
Data Availability
The authors declare that all data supporting this study are included in the manuscript and Supplementary Table S1.

Figure 1. Conceptual framework developed by combining the Figley Compassion Stress and Fatigue Model with the Stamm Professional Quality-of-Life framework. Solid arrows represent risk-associated pathways from workload and trauma exposure, while dashed arrows represent inverse protective-associated pathways involving adaptive coping and compassion satisfaction. Please click here to view a larger version of this figure.

Figure 2. Workflow of the experimental protocol. Please click here to view a larger version of this figure.

Figure 3. Pairwise correlation heatmap for CF, workload, trauma exposure, coping mechanisms, and compassion satisfaction. Positive values indicate direct pairwise associations and negative values indicate inverse pairwise associations; all displayed correlations had p < 0.001. Please click here to view a larger version of this figure.

Figure 4. Distribution of compassion-fatigue scores across low, moderate, and high coping categories. Please click here to view a larger version of this figure.

Figure 5. Mean compassion-fatigue scores across ED-experience groups with 95% confidence intervals. Please click here to view a larger version of this figure.

Figure 6. Comparison of mean compassion-fatigue and compassion-satisfaction scores across coping categories. Please click here to view a larger version of this figure.

Figure 7. Standardized regression coefficients with 95% confidence intervals. Please click here to view a larger version of this figure.

Figure 8. Residual-versus-fitted and normal Q-Q diagnostic plots for the four-predictor regression model. Please click here to view a larger version of this figure.

Figure 9. Visual comparison of accuracy, precision, recall, and F1-score across the three classifiers. Please click here to view a larger version of this figure.
| Variable | Operational definition | Scale and direction | Analytical role |
| Gender | Self-reported gender category | Male/Female as reported; categorically encoded | Demographic descriptor |
| Age | Age at study time | Years; continuous | Demographic descriptor |
| ED experience | Completed years working in emergency nursing | 1–5, 6–10, or 11–15 years | Group variable |
| Workload | Perceived cumulative demand from patient volume, acuity, interruptions, documentation, staffing constraints, shift intensity, and cognitive-emotional load | 1–10; high scores indicate high workload | Primary predictor |
| Trauma exposure | Perceived frequency and intensity of encounters with severe injury, death, violence, and patient suffering | 1–10; high scores indicate high exposure | Primary predictor |
| Coping mechanisms | Frequency and effectiveness of adaptive stress-management responses, including support seeking, reflective processing, and recovery practices | 1–5; high scores indicate more adaptive coping | Primary predictor |
| Compassion satisfaction | Positive fulfillment derived from helping patients and performing meaningful nursing work | 1–7; high scores indicate high satisfaction | Primary predictor |
| Compassion fatigue | Study-specific rating of emotional exhaustion, reduced empathic capacity, and distress related to caregiving | 1–10; higher scores indicate greater CF | Primary outcome |
| Binary CF label | Binary outcome used for model comparison | Exact cut-point was not retained | Exploratory classification target |
Table 1: Definitions, score ranges, coding directions, and analytical roles for demographic descriptors, the four prespecified predictors, the continuous CF outcome, and the source binary CF label. The 1-10 CF score was derived from the study-specific questionnaire and was not calculated using the ProQOL instrument; it is used as guidance. The original analysis reported a binary CF outcome; however, because the numerical threshold used to define that outcome was not retained in the available study records, threshold-dependent classification metrics are presented only as exploratory internal results and should not be interpreted as clinically validated risk estimates. Abbreviations: CF = compassion fatigue; ProQOL = Professional Quality of Life.
| Characteristic | Category/value | n | % | Mean | SD |
| Gender | Male | 90 | 60 | - | - |
| Gender | Female | 60 | 40 | - | - |
| Age (years) | Overall | - | - | 32 | 5.2 |
| ED experience | 1–5 years | 50 | 33.3 | - | - |
| ED experience | 6–10 years | 60 | 40 | - | - |
| ED experience | 11–15 years | 40 | 26.7 | - | - |
| Workload | 1–10 scale | - | - | 7.8 | 1.4 |
| Trauma exposure | 1–10 scale | - | - | 6.5 | 1.2 |
| Coping mechanisms | 1–5 scale | - | - | 3.2 | 0.7 |
| Compassion satisfaction | 1–7 scale | - | - | 4.5 | 1.1 |
| Compassion fatigue | 1–10 scale | - | - | 5.1 | 1.3 |
Table 2: Demographic and work-related characteristics of the 150 ED nurses, reported as counts, percentages, means, and standard deviations as applicable.
| Analysis | Statistic | p value(s) | Interpretation |
| Shapiro-Wilk by ED-experience group | W = 0.968, 0.981, 0.975 | p = 0.196, 0.463, 0.526 | Normality acceptable |
| Levene test | F (2,147) = 1.34 | p = 0.266 | Equal variances supported |
| One-way ANOVA | F (2,147) = 5.14 | p = 0.007 | eta-squared = 0.065 |
| Kruskal-Wallis | H (2) = 26.81 | p < 0.001 | epsilon-squared = 0.169 |
Table 3: Assumption checks and omnibus group-comparison results for the N = 150 dataset.
| Method | Comparison | Effect/statistic | Adjusted p | Significant |
| Tukey HSD | 1 vs 2 | 0.367 | 0.2878 | No |
| Tukey HSD | 1 vs 3 | 0.86 | 0.0047 | Yes |
| Tukey HSD | 2 vs 3 | 0.493 | 0.1394 | No |
| Dunn-Bonferroni | 1 vs 2 | z = 1.219 | 0.668 | No |
| Dunn-Bonferroni | 1 vs 3 | z = 4.905 | <0.001 | Yes |
| Dunn-Bonferroni | 2 vs 3 | z = 4.024 | <0.001 | Yes |
Table 4: Pairwise post-hoc comparisons with multiplicity-adjusted p-values
| Experience group | n | Mean CF | Mean workload | Mean trauma exposure | Mean coping |
| 1-5 years | 50 | 4.72 | 7.33 | 6.34 | 3.3 |
| 6-10 years | 60 | 5.09 | 8.01 | 6.35 | 3.21 |
| 11-15 years | 40 | 5.58 | 8.07 | 6.93 | 3.07 |
Table 5: Group sizes and mean compassion-fatigue, workload, trauma-exposure, and coping scores across ED-experience groups.
| Coping category | n | Mean CF | Mean workload | Mean trauma exposure | Mean compassion satisfaction |
| Low | 45 | 5.71 | 7.86 | 6.57 | 4 |
| Moderate | 60 | 5.28 | 8.12 | 6.51 | 4.4 |
| High | 45 | 4.24 | 7.3 | 6.42 | 5.13 |
Table 6: Group sizes and mean compassion-fatigue, workload, trauma-exposure, and compassion-satisfaction scores across coping categories.
| Component | Statistic | Interpretation |
| Model fit | R2 = 0.856; adjusted R2 = 0.852 | F (4, 145) = 215.16, p < 0.001 |
| Residual normality | Shapiro-Wilk W = 0.983 | p = 0.059 |
| Homoscedasticity | Breusch-Pagan LM = 5.09 | p = 0.278 |
| Error independence | Durbin-Watson = 1.97 | Acceptable |
| Influential observations | Maximum Cook's distance = 0.063 | No highly influential case |
Table 7: Overall regression model fit and diagnostic statistics for the N = 150 dataset.
| Predictor | Standardized beta (SE) | 95% CI | p value | VIF | Tolerance |
| Workload | 0.419 (0.038) | [0.344, 0.494] | <0.001 | 1.44 | 0.7 |
| Trauma Exposure | 0.323 (0.036) | [0.251, 0.394] | <0.001 | 1.33 | 0.75 |
| Coping Mechanisms | -0.247 (0.037) | [-0.320, -0.175] | <0.001 | 1.35 | 0.74 |
| Compassion Satisfaction | -0.350 (0.038) | [-0.425, -0.274] | <0.001 | 1.45 | 0.69 |
Table 8: Standardized regression coefficients, 95% confidence intervals, p values, variance inflation factors, and tolerance values for the four-predictor model.
| Model | Accuracy (%) | Precision (%) | Recall (%) | F1-score (%) | AUC-ROC |
| Logistic regression | 80 | 78 | 75 | 76 | 0.8 |
| Random Forest | 85 | 82 | 80 | 81 | 0.84 |
| Support Vector Machine | 83 | 80 | 77 | 78 | 0.83 |
Table 9: Reported aggregate accuracy, precision, recall, F1-score, and ROC-AUC for logistic regression, Random Forest, and Support Vector Machine.
Supplementary Table S1: Dataset supporting the study. Please click here to download this file.