1. Introduction
The ability of a company to identify the risk of financial failure in a timely manner is a fundamental management tool. Bankruptcy prediction is a widely researched topic (
Dasilas & Rigani, 2024), as bankruptcy typically results from a chain of negative events, making it difficult to pinpoint a single cause of overall failure. Research has shown that the financial ratios of prosperous companies differ significantly from those of bankrupt companies well before bankruptcy occurs (
Karas, 2017;
Vochozka et al., 2020). A financially healthy company is one that can meet its obligations on time while also generating profit (
Csikosova et al., 2019;
Horváthová et al., 2021;
Nagy & Valaskova, 2023).
This applies to standard economic periods. However, during a crisis, prediction accuracy tends to deteriorate, as noted by
Papík and Papíková (
2023).
Duricova et al. (
2025) confirm that using a pre-crisis model during a crisis period without adjustments significantly reduces accuracy. They also demonstrate that recalibrating model coefficients can restore accuracy to pre-crisis levels. Notably, these models were based on discriminant analysis (DA), which is inherently less stable than AI-based models when applied to different datasets. This suggests that, while prediction models can be designed similarly for both crisis and non-crisis periods, applying a model trained on non-crisis data during a crisis is not advisable. Similarly, a model designed for crisis periods may underperform in a standard economic environment.
Small and medium-sized enterprises (SMEs), in particular, face financial constraints and liquidity challenges during economic shocks, such as the COVID-19 pandemic. Lockdown imposed during the crisis significantly increased the risk of insolvency for many small businesses (
Cowling et al., 2020). Limited access to financing makes SMEs especially vulnerable to changing economic conditions. Often perceived as riskier by creditors, SMEs cannot be evaluated using the same financial metrics as large enterprises. These financial constraints further exacerbate their risk of bankruptcy (
Karas & Režňáková, 2021).
Calabrese (
2023) highlights the interconnected nature of SME bankruptcies, especially during periods of economic downturn.
In this study, the analyzed period was influenced by the COVID-19 crisis. To enable better analysis and comparison, the period immediately following the crisis was also included. Developing models under crisis conditions provides a foundation for future comparisons with standard economic periods. To our knowledge, no machine learning (ML) model can predict bankruptcy with equal accuracy in both crisis and non-crisis periods. However, analyzing different economic phases allows for meaningful comparison and the identification of common factors that serve as reliable predictors across varying conditions.
Only a limited number of studies have examined differences between crisis and post-crisis periods in the context of bankruptcy prediction. In particular, the impact of a crisis on prediction models within a transitional economy such as Slovakia remains insufficiently explored. This study seeks to address this research gap by analyzing bankruptcy prediction under specific economic conditions and by empirically examining how crisis-related shocks influence model performance. Further development of the predictive potential of machine learning models and their application across different economic environments continues to represent a significant research challenge. Moreover, the use of diverse types of indicators remains relatively underexplored, as existing studies tend to focus predominantly on financial variables. The effects of a crisis of the magnitude of the COVID-19 pandemic on predictive modeling require more thorough investigation, especially in economies composed predominantly of SME. A review of the literature indicates that bankruptcy prediction research primarily concentrates on large corporations or publicly traded companies. By proposing and testing models within the unique context of a transitional economy, this study contributes to the empirical examination of crisis effects on bankruptcy prediction in SME-dominated environments.
One of the most widely used models for bankruptcy prediction is logistic regression (LR) (
Jabeur, 2017;
Kristóf & Virág, 2020;
Huo et al., 2024;
Khashei et al., 2024). However, with technological advancements and increasing computing power, artificial intelligence (AI) techniques have undergone continuous improvement. Numerous studies suggest that neural networks (NN) outperform traditional statistical methods in financial prediction (
López Iturriaga & Sanz, 2015;
Fischer & Krauss, 2018,
Gregova et al., 2020;
Kurani et al., 2023). Yet, important questions remain: Can modern ML methods completely replace LR models, and how much more effective are techniques such as artificial neural networks (ANNs), decision trees (DTs), and support vector machines (SVMs) in predicting bankruptcy? These questions form the basis of this research.
This paper aims to develop a predictive model tailored to the specific conditions of the Slovak Republic during and after the crisis period. The Slovak capital market is less developed than those of larger economies, and a high proportion of businesses are SMEs, making them particularly vulnerable to financial distress. SMEs face greater challenges in securing financing compared to larger companies (
Bakhtiari et al., 2020;
Serrasqueiro et al., 2021). The COVID-19 pandemic and the subsequent war in Ukraine have had global repercussions, affecting numerous macroeconomic indicators, including inflation, GDP, interest rates, and unemployment (
Tetteh & Ntsiful, 2023). Although the COVID-19 crisis did not formally alter bankruptcy criteria, enforcement was relaxed, and temporary support measures allowed weaker or unprofitable firms (so-called zombie companies) to survive longer than they would have under normal conditions. This increased tolerance for such firms raises concerns about post-pandemic economic productivity. The selected crisis period for analysis, 2020–2021, was heavily influenced by the pandemic and associated challenges such as the chip shortage, energy crisis, and high inflation. The results of this predictive analysis will serve as a valuable reference for future research, enabling comparisons between bankruptcy rates during the crisis and in the post-crisis period.
Bankruptcy trends in Slovakia (
OECD, 2022) indicate that, to mitigate the economic impact of the COVID-19 pandemic, the government implemented a temporary moratorium on insolvency filings until the end of 2020, providing short-term relief to businesses. In 2021, legislative amendments allowed temporary bankruptcy moratoria of up to six months and facilitated out-of-court pre-insolvency restructuring, giving companies additional options to manage financial difficulties. According to
Eurostat (
2022), the number of bankruptcy declarations increased from 2018 to 2021 but declined from 2022 onward (see
Table A5 in
Appendix D).
Compared to normal economic periods, the pandemic-affected period was unprecedented and unique. Drastic changes such as lockdown, movement restrictions, and extended receivables maturity have significantly affected business performance. These fundamental macroeconomic shifts also influence the accuracy of bankruptcy prediction models. This raises a question: To what extent have these changes affected the ability of models to distinguish between bankrupt and non-bankrupt companies? Moreover, can standard prediction methods be effectively applied in non-standard economic conditions, or is it necessary to incorporate additional qualitative indicators?
Existing literature highlights the superiority of AI techniques over LR during standard economic periods, as evidenced by (
López Iturriaga & Sanz, 2015;
Korol & Fotiadis, 2022;
Silva et al., 2023;
Fasano et al., 2024). However, the impact of the economic crisis on the predictive accuracy of these models remains unclear. While some studies report a decline in performance, others suggest potential improvements under certain conditions. Research by
Papík and Papíková (
2023) indicates that model validation accuracy tends to decline during crisis periods.
A crucial question remains: How do different prediction methods perform during periods of significant external disruptions? Specifically, can LR accurately predict bankruptcy solely based on financial ratios during a crisis, or do external factors necessitate a more sophisticated modeling approach?
The structure of this paper is organized as follows:
Section 2 presents a theoretical framework, covering the fundamentals of bankruptcy prediction, modeling approaches, and reported findings.
Section 3 describes the data and methodology, including a brief overview of the applied machine learning techniques and the evaluation metrics used to assess prediction performance.
Section 4 reports the results and discusses the findings, including the study’s limitations. Finally, the conclusion summarizes the key results, outlines the main limitations, and highlights the study’s contributions.
2. Theoretical Framework
Predictive models play a crucial role not only in business management (
Iscaro et al., 2022), where they function as an early warning system, but also for creditors, enabling more accurate risk assessment of investments. Bankruptcy typically does not occur suddenly; rather, it results from a series of failures and poor decisions. According to
Samarina et al. (
2022), bankruptcy is an essential component of the market system, designed to protect socio-economic processes from the inefficiencies of failing entities. Consequently, inefficient firms are eliminated from the market, allowing resources to be reallocated from less efficient to more efficient owners. Similarly,
Kitowski et al. (
2022) argue that bankruptcy functions as a self-regulatory market mechanism and constitutes a necessary condition for sustainable market development. On the other hand, bankruptcy may also function as a legal safeguard against aggressive actions by creditors. The formal declaration of bankruptcy represents a last-resort mechanism for the settlement of claims and provides the debtor with an opportunity to restructure outstanding obligations. The initiation of bankruptcy proceedings typically results in an automatic suspension of debt enforcement and offers temporary protection to the entrepreneur from creditor actions. In this manner, the debtor’s assets become subject to centralized administration and oversight.
The pandemic caused a loss of income and reduced labor productivity. Although companies tried to compensate for this shortfall by reducing income, even that was not always enough. To avert massive layoffs and a large increase in bankruptcies, the government decided to mitigate the economic downturn by subsidizing costs, especially in the most affected sectors such as gastronomy and agritourism. This support mitigated the risk of illiquidity and insolvency. Companies that were primarily directly affected by the closure of operations resulting from government regulations could apply for subsidies. However, support also reached, to a lesser extent, companies demonstrating a decrease in sales due to the pandemic.
SMEs are a fundamental part of the EU’s market economy, making the study of their insolvency particularly important. They account for over 99% of all enterprises in the EU, with the latest data from
Statista (
2024) indicating a 99.8% share (
Botsari et al., 2024). The EU classifies SMEs as enterprises with fewer than 250 employees and either an annual turnover of less than €50 million or total assets not exceeding €43 million. Survival during the initial years is critical for small businesses. According to
Mrockova (
2022), less than half of small enterprises in OECD countries survive beyond their first five years. These survival challenges underscore the importance of accurately predicting bankruptcy risks, a task that has become increasingly vital for understanding the vulnerabilities of SMEs.
The origins of bankruptcy prediction can be traced back to
Fitzpatrick (
1932), who compared financial ratios of healthy and bankrupt companies.
Beaver (
1966) later introduced univariate analysis, and
Altman (
1968) developed the well-known Z-score model using five predictors. Subsequent advancements included the application of Probit models by
Ohlson (
1980) and
Zmijewski (
1984), as well as logit models by
Hanweck (
1977) and
Zavgren (
1983). With the development of computer technology,
Odom and Sharda (
1990) introduced ANNs for bankruptcy prediction, followed by
Han et al. (
1996), who employed DTs. Literature analysis shows frequent comparison of the performance of different prediction models, including LR, DTs, SVMs, ANNs (
López Iturriaga & Sanz, 2015;
Shin et al., 2005;
Yoon & Kwon, 2010;
Zhou et al., 2012;
Lee & Su, 2015;
Hosaka, 2019;
Gavurova et al., 2022;
Aydin et al., 2022;
Andresson & Lukason, 2024), random forest (RF) (
Silva et al., 2023;
Cheraghali & Molnár, 2025;
Hamdi et al., 2024), Naïve Bayes (
Chen et al., 2021;
Máté et al., 2023;
Kaleem et al., 2024;
Dhamo et al., 2025), and Boost (
Kim & Kang, 2010;
Barboza et al., 2017;
du Jardin, 2018;
Ptak-Chmielewska, 2019;
Sigrist & Leuenberger, 2023;
Wei et al., 2024).
Today, researchers continue to refine and enhance prediction models.
Cho et al. (
2010) applied DTs for variable selection using Mahalanobis distance with weighted variables, creating a hybrid model on Korean data.
Kim and Kang (
2010) improved ANN performance through bagging and boosting techniques.
Callejón et al. (
2013) empirically demonstrated the predictive power of ANN models in European industrial companies, applying their models to data from two years prior to bankruptcy. In the U.S.,
López Iturriaga and Sanz (
2015) combined self-organizing maps (SOM) and multi-layer perceptrons (MLP) to predict bankruptcy up to three years in advance, proving the superiority of AI techniques over LR and highlighting the benefits of hybridized models.
Jabeur (
2017) applied Partial Least Squares Logistic Regression (PLS-LR) on French data, improving results for correlated variables. A comparative study by
Alaka et al. (
2018) found no significant difference in predictive accuracy among various methods, including LR, ANNs, SVMs, DTs, and genetic algorithms (GAs). Similarly,
du Jardin (
2018) conducted a large-scale comparison on French enterprises, showing no clear superiority of any specific model. His results indicate that while AI techniques such as DTs, LR, SVMs, and ANNs—along with hybrid and ensemble methods—can achieve strong predictive performance, none consistently outperforms the others. This conclusion supports the ongoing debate regarding the true power of predictive models. While ML techniques have demonstrated significant advantages, traditional methods like LR remain viable. However, DA techniques consistently yield weaker results compared to ML models, as shown by (
Horváthová et al., 2021,
Odom & Sharda, 1990,
Shin et al., 2005;
Barboza et al., 2017;
Wei et al., 2024;
Alaka et al., 2018;
Agarwal, 1999;
Korol, 2020). Recent advancements have explored specialized AI models.
Hosaka (
2019) applied convolutional neural networks (CNNs) by converting financial indicators into grayscale images, outperforming traditional models such as classification and regression trees (CART), SVMs, and AdaBoost. Similarly,
Becerra-Vicario et al. (
2020) employed CNNs for bankruptcy prediction.
Chen et al. (
2021) developed a hybrid system for Taiwanese enterprises, optimizing financial attribute selection and comparing performance with LR.
Korol and Fotiadis (
2022) applied feature selection and GA on Polish and Taiwanese data, focusing on personal bankruptcy prediction and comparing results with LR. The advantages of ensemble methods (bagging and boosting) have been widely demonstrated in (
Papík & Papíková, 2023;
Chen et al., 2021;
Máté et al., 2023;
Ptak-Chmielewska, 2019;
Sigrist & Leuenberger, 2023).
Most bankruptcy prediction models focus on financial ratios, which, during standard economic periods, can effectively distinguish between bankrupt and financially stable companies. The inclusion of specific variables can enhance predictive accuracy by capturing relationships between available financial information and eventual bankruptcy. However, some studies suggest that incorporating non-financial indicators does not always improve model performance.
Papík and Papíková (
2023) found that adding categorical qualitative variables often requires excessive computational effort without a corresponding increase in accuracy. Similarly,
Michalkova and Ponisciakova (
2025) analyzed the reliability of bankruptcy prediction models in the context of corporate life cycle stages, using a sample of EU SMEs.
Alternative predictive indicators have also been explored.
Korol and Fotiadis (
2022) verified the predictive power of demographic data, while
Tobback et al. (
2017) examined relational data from networks of top managers connected to bankrupt firms. Despite the potential added value of these approaches, access to such data is highly restricted in some countries, including Slovakia.
Arcuri and Levratto (
2020) investigated the influence of local financial markets on bankruptcy prediction, making it one of the few studies to examine institutional characteristics within a regional context. Other researchers have sought to integrate environmental, social, and governance factors into predictive models, arguing that these non-financial variables enhance accuracy (
Kaleem et al., 2024).
Calabrese (
2023) analyzed the interdependence of SME bankruptcies during crisis periods, while
Kwon and Lee (
2018) leveraged industry-specific hidden factors to improve predictive performance.
Various studies highlight different determinants of SME bankruptcy.
Karas and Režňáková (
2021) examined financial constraints,
Campa (
2015) assessed the relationship between earnings management and bankruptcy, and
Wei et al. (
2024) explored inter-firm associations and lender-borrower relationships. Some researchers argue that financial ratios alone are insufficient for SME bankruptcy prediction (
Andresson & Lukason, 2024). Others have introduced alternative models, such as hazard models (
Gupta et al., 2015) or macroeconomic indicators like GDP growth and interest rates (
Asgarnezhad Nouri & Soltani, 2016). Additional studies have incorporated broader industry, environmental, and security factors (
Andrikopoulos & Khorasgani, 2018;
Rikkers & Thibeault, 2011;
Belaid et al., 2017).
Traditional scoring models rely on market-based data, which generally reflect a company’s current financial situation more accurately than historical financial ratios. However, structural models are often unsuitable for SMEs, as they require stock market data that are typically unavailable (
Karas & Režňáková, 2021). Although integrating additional factors can enhance prediction models, this study does not focus on the role of non-financial variables in bankruptcy prediction. As
Perez (
2006) noted in his systematic review, most studies rely on quantitative indicators due to their electronic availability, while the lack of qualitative data limits broader applications.
Accuracy remains one of the most critical performance measures in bankruptcy prediction models, given its economic implications (
Kim & Kang, 2010). Several factors influence predictive accuracy, including sample size, dataset balance, variable selection, industry-specific factors, and data sources (
Clement et al., 2022). Additionally, data-driven predictive models tend to perform better in the short term, with their accuracy declining over time (
Papana & Spyridou, 2020).
Overall, a significant portion of the literature highlights the contributions of ML to bankruptcy prediction. While some studies indicate the superiority of AI techniques over LR, others suggest a general balance between methods. However, AI models at least match the performance of LR, suggesting that traditional methods still hold value in predictive analysis. The potential of AI techniques remains vast, and their application continues to evolve, offering continuous improvements in predictive accuracy.
Table 1 provides an overview of studies focused on bankruptcy prediction, highlighting which method achieved the best results in each case. It also indicates the frequency with which each method was employed and how often it was identified as the most effective. Among ML techniques, the most frequently used—excluding hybrid, specialized, and ensemble methods—are NNs, SVMs, and DTs. LR, as a traditional statistical method, remains widely used due to its historical prominence. In recent years, ensemble methods have gained popularity, often delivering superior results through various optimization strategies. Similarly, RFs have become more prevalent due to their built-in ability to optimize decision tree selection automatically.
4. Results and Discussion
The selection of ML methods for comparison with the LR model was primarily based on the comparative study by
Alaka et al. (
2018), which found that ANNs, SVMs, and DTs performed similarly to LR. Their study also reported the frequency of use of various methods in the literature, showing that NN were the most frequently employed, followed by LR, SVM, multiple discriminant analysis (MDA), and DT. Another key source was
du Jardin (
2018), whose findings also indicated no statistically significant performance differences among basic classification methods. His work extended the comparison to ensemble and hybrid techniques. Although these advanced models often demonstrate superior predictive performance, they were not implemented in this study due to their higher requirements for model design, data processing, and computational complexity—factors that fall outside the intended scope of our research. Based on the popularity of the individual methods reported by the authors and summarized in
Table 1, a statistical overview was created to identify the techniques most frequently used and those most often evaluated as the best-performing (see
Table 4). According to the frequency of use, NNs, LR, SVMs, and DTs emerged as the most applied methods, generally achieving the best results (when specific model variations are not considered). Consequently, these methods were selected for use in this study. While ensemble methods—by enhancing base learners through various optimization strategies—are considered highly promising, they are better categorized as advanced tools rather than basic classification methods. Similarly, hybrid models can be advantageous but involve substantial design and implementation complexity. For these reasons, the present study focuses exclusively on the comparison of basic methods, excluding ensemble and hybrid approaches.
The prediction results for all models are summarized in
Table 5. For a comprehensive comparison, the F-measure metric was chosen, as it provides a more balanced assessment of model performance compared to accuracy. The results obtained from all applied methods were highly similar. One possible explanation is that the available data may not contain sufficient additional information to improve prediction accuracy without increasing the risk of overfitting. To better distinguish the performance of individual methods, a larger research sample, the inclusion of more—particularly qualitative—variables, or testing across different datasets (e.g., from different time periods, industries, or countries) would be necessary. Although LR achieved the lowest score in all cases, the difference was statistically very small. The comparable performance between LR and ML models suggests that LR is equally capable of capturing the relationship between financial indicators and the likelihood of bankruptcy. Another explanatory factor may be the use of identical input variables for all models, which may have limited each model abilities to fully leverage its unique strengths. While each method offers distinct methodological advantages, the aim of this study was to evaluate them under consistent conditions rather than to achieve optimal predictive accuracy.
Accuracy is a commonly used metric for evaluating model performance. However, its effectiveness diminishes considerably when applied to unbalanced datasets. Although the dataset in this study is balanced, the F-measure was chosen as the primary evaluation metric to enhance reliability. The F-measure considers both precision and recall, providing a more robust and informative indicator of predictive performance. The F-measure reflects the overall predictive ability and accuracy of the model. Additional metrics, such as accuracy, sensitivity, specificity, and precision, also serve as by-products of the evaluation process. Sensitivity helps determine Type I error (i.e., a bankrupt company incorrectly classified as healthy), while specificity helps determine Type II error (i.e., a healthy company incorrectly classified as bankrupt). The F-measure results of all models demonstrate strong predictive performance, confirming the validity of the modeling approach. A comparison of these models, presented in
Table 6, under similar conditions in Slovakia aligns with findings from previous studies (
Horváthová et al., 2021;
Papík & Papíková, 2023;
Gregova et al., 2020;
Gavurova et al., 2022;
Tumpach et al., 2020;
Jenčová et al., 2020;
Letkovský et al., 2024;
Brozyna et al., 2016;
Mihalovič, 2018;
Valaskova et al., 2023). Comparable research has also been conducted in the Czech Republic (
Vochozka et al., 2020;
Horak et al., 2020) and across the EU (
Csikosova et al., 2019;
Karas & Režňáková, 2021).
While the developed models demonstrate competitive predictive performance, direct comparisons are challenging due to variations in datasets and methodologies. For example,
Jenčová et al. (
2020) and
Horváthová et al. (
2021) focused on specific industries, enabling more precise differentiation between bankrupt and non-bankrupt companies, as financial data varies significantly across industries. Nonetheless, the models developed in this study could be applied in other EU countries with similar economic conditions, demonstrating their broader applicability and relevance.
Overall, the models exhibited a slight improvement in accuracy during the post-crisis period; however, this difference was not statistically significant. The comparison of model performance was conducted using the nonparametric McNemar test, which is designed to evaluate differences in paired nominal data within the same sample. The performance of DT, SVM, and ANN models was statistically compared to that of LR. The results of the McNemar test are presented in
Table 7. This observation can be partly explained by the increased sample size in the post-crisis dataset, which reflects the expanding number of enterprises within the Slovak industrial sector. The relative accuracy of the models suggests that no significant changes occurred during the crisis period that would render traditional prediction methods ineffective. While a slight decrease in accuracy is likely, this aligns with
Papík and Papíková (
2023), who demonstrated that economic crises negatively impact model accuracy compared to pre-crisis periods. However, the present study did not specifically quantify the magnitude of this effect due to its scope.
The primary objective was to determine whether bankruptcy prediction remains feasible during a crisis period using similar methods and to evaluate whether the LR model continues to perform comparably to AI-based techniques under such conditions.
The results indicate that all evaluated models exhibit relatively strong predictive performance, with only minor differences in their effectiveness. When only financial indicators were used, the LR model recorded the lowest F-measure, with values of 0.845 in 2020 and 0.862 in 2022. After the inclusion of qualitative indicators, achieving an F-measure of 0.839 in 2020 and 0.864 in 2022; however, the variation across models remained minimal. The highest predictive performance was observed for the ANN, which reached an F-measure of 0.892 (2020) and 0.898 (2022). In both cases, the LR model recorded the lowest performance among models using all available indicators, though the differences were not significant. Overall, ML models—specifically SVMs, DTs, and ANNs—outperformed the classical LR model in terms of predictive accuracy. When the predictions were repeated without including additional variables such as company size, the results were largely comparable. An interesting phenomenon can be observed in the slight increase in accuracy following the inclusion of the firm size variable in the LR and SVM models, accompanied by a decrease in accuracy in the DT and NN models in 2020. In the post-crisis period (2022), this relationship was reversed, with a decline in accuracy in the LR and SVM models and an improvement in the DT and NN models. However, these differences cannot be considered statistically significant. This reversal may indicate that the importance of firm size as a predictive variable changed between the crisis and post-crisis periods. During the crisis, firm size could have acted as a stabilizing factor, improving the performance of linear models such as LR and SVMs, whereas in the post-crisis environment, non-linear models like DTs and NNs may have been better able to capture the more complex relationships between firm size and financial distress. Although a slight decrease in accuracy was observed, the difference was negligible, suggesting that these variables did not significantly enhance predictive performance. The relative importance of individual predictors in the DT model is presented in
Table 8.
The analysis reveals that the company size is the least significant predictor, contributing to only 2%. In the LR model, size is identified as a significant variable (
p < 0.001), with a negative effect on the dependent variable. This finding aligns with the study by
Papík and Papíková (
2023), which also demonstrated that adding categorical non-financial variables did not enhance prediction accuracy significantly. A possible explanation is that only SMEs were included in the dataset, and these enterprises operate under similar conditions in Slovakia. Consequently, these non-financial variables do not provide meaningful information for bankruptcy prediction. To quantify the impact of this factor, the statistics in
Table 9 were calculated, comparing a model without company size (M
0) to a model including it (M
1). The low values of McFadden R
2, Nagelkerke R
2, and Cox and Snell R
2 confirm that the model incorporating this predictor provides only a negligible improvement over the null model. The LR coefficients are presented in
Table 10, and the ROC curves illustrating models’ performance are shown in
Figure 3. The LR model labeled M
0 includes all five selected (uncorrelated) financial indicators, together with a non-financial variable (company size). Based on the Wald test, which indicated that some predictors contributed minimally to the model (i.e., exhibited high
p-values), a reduced model labeled M
2 was developed. Model M
2 retains only the three (2020) and four (2022) most significant predictors: company size, VI/A, ROA in 2020, and CA in 2022. The reduction process followed the backward stepwise elimination method, in which variables are systematically removed to optimize model simplicity without compromising predictive power. The model verification statistics presented in
Table 11—including McFadden R
2, Nagelkerke R
2, and Cox and Snell R
2—show values close to zero, confirming that the reduced model performs comparably to the full model. Furthermore, the predictive accuracy of the LR model using M
2 remained largely unchanged, supporting the conclusion that the excluded indicators did not significantly improve or decrease model performance. Similarly, for the SVM model, the decision boundary matrix across all predictors is shown in
Figure A3 for 2020 and
Figure A4 for 2022 in
Appendix C. Stepwise selection is generally discouraged in ML because it can lead to overfitting, relies on unstable statistical tests, ignores potential non-linear relationships between variables, and does not optimize predictive performance. Therefore, in this study, it was applied only to the LR model and not to ML methods.
Our analysis identified five key predictors that significantly contributed to bankruptcy prediction, achieving an accuracy level between 84% and 90%. Among these, VI/A emerged as one of the most influential indicators, with a relative importance of 37% according to the DT model. This metric reflects the extent of self-financing within a company and its capital structure, making it a strong predictor of financial stability. Its significance in bankruptcy prediction is supported by studies such as (
Shin et al., 2005;
Ptak-Chmielewska, 2019). VI/A also indirectly indicates indebtedness, providing complementary information to total debt levels. Given its close relationship with financial leverage, it would be valuable to exclude this predictor from the analysis to assess its impact on prediction accuracy. Liquidity predictors also played a crucial role, with the current ratio (L3) accounting for 21% of importance in the DT model. This differs from the LR model, where the indicator was found to be insignificant (
p = 0.838 in 2020 and
p = 0.244 in 2022). This ratio measures a company’s ability to promptly meet short-term obligations and reflects solvency. Its predictive relevance is consistent with findings of previous studies (
Cheraghali & Molnár, 2025;
Alexandridis & Zapranis, 2013;
Nagelkerke, 1991;
Cox & Snell, 1989). Similarly, NWC/A, which represents the proportion of working capital allocated to assets, contributed 21% to the prediction accuracy in the DT model. In the LR model, this indicator was marked as insignificant (
p = 0.967 in 2020 and
p = 0.204 in 2022). This metric highlights a company’s ability to cover short-term liabilities with available assets, an essential aspect of financial health. Its relevance in bankruptcy prediction has been previously demonstrated by several studies (
Jabeur, 2017;
Ogachi et al., 2020;
Letkovský et al., 2024;
Yousaf & Bris, 2021), with its importance tracking back to Altman’s seminal research (
Altman, 1968). Another critical predictor, ROA, reflects the efficiency of asset utilization, indicating the proportion of profit generated relative to total assets. Its significance in bankruptcy prediction is intuitive, as a company that fails to generate sufficient returns from its assets is at a higher risk of financial instability. Insufficient profitability and a shortage of short-term assets can serve as early warning signals of impending failure. Finally, CA, which measures liquidity relative to assets, also proved to be a strong predictor, in line with the findings of
Korol (
2020). However, this indicator was marked as insignificant or irrelevant across all models.
The LR model (M2) indicates that all three predictors (size, VI/A, ROA) have odds ratios lower than 1, suggesting a negative relationship with the likelihood of bankruptcy. Low value of odds ratio for company size confirms the well-established notion in the literature that firm size acts as a strong protective factor, as larger firms typically possess greater access to financing, higher diversification, and stronger market positions, which enhance their financial stability. The odds ratio for the equity-to-total-assets ratio (9.625 × 10−20 in 2020 and 5.932 × 10−8 in 2022) indicates a strong negative relationship with bankruptcy likelihood. This suggests that firms with higher equity relative to their total assets are substantially less likely to go bankrupt. In economic terms, equity-rich firms have greater financial resilience and lower dependence on external debt, which significantly improves their solvency position. The odds ratio for the return on assets (ROA) variable was found to be 0.093 (or 0.318), depending on the model specification. In both cases, the value is below 1, which indicates a negative relationship between ROA and the likelihood of bankruptcy. This means that as profitability increases, the probability of bankruptcy decreases. Specifically, a one-unit increase in ROA reduces the odds of bankruptcy by approximately 90.7% when the odds ratio is 0.093 (2020), and by 68.2% when the odds ratio is 0.318 (2022). These results confirm that ROA is a strong protective indicator of financial health and stability. Firms with higher profitability are therefore significantly less likely to experience financial distress. The differences in the magnitude of the odds ratio across models may be attributed to variations in model specification, data structure, or the inclusion of other correlated indicators. Nonetheless, the consistent direction of the effect across models reinforces the importance of profitability as a determinant of bankruptcy risk. Similarly, the cash-to-assets ratio (CA) has an odds ratio of 0.48, meaning that a one-unit increase in liquidity corresponds to a 52% reduction in the odds of bankruptcy. This finding highlights the importance of liquidity in maintaining operational continuity and meeting short-term obligations. Overall, the results demonstrate that larger, more liquid firms with stronger asset-related financial ratios are significantly less likely to go bankrupt. These predictors, therefore, serve as important protective factors in bankruptcy prediction models.
According to the results obtained, although the set of predictors remained unchanged, their relative weights shifted slightly, which is a natural outcome. These predictors appear to be reliable and stable indicators, even during the crisis period. The prediction accuracy increased slightly in the post-crisis period, which is expected, as forecasting tends to be more accurate under stable economic conditions. This finding further supports the conclusion that bankruptcy is more predictable in non-crisis periods.
It is also likely that, thanks to government support measures, many SMEs managed to survive this unprecedented crisis period, whereas under normal circumstances, they might not have been able to. Consequently, when analyzing the data, we do not observe the dramatic structural changes in bankruptcy patterns that might have been expected. The impact of the pandemic seems to have spread out over time, thereby reducing its intensity. Of course, there is no doubt about the negative impact on businesses, as evidenced by the increased number of bankruptcies observed in the post-crisis period. This trend is partly attributable to the overall rise in the number of active entities.
Some studies have reported improvements in accuracy when applying the LASSO method, raising the question of whether alternative selection techniques could extract additional information and enhance model performance (e.g.,
Cheraghali & Molnár, 2025;
Ozturkkal & Wahlstrøm, 2025;
Pereira et al., 2016). Based on the results of the Wald statistic in the LR model, several indicators exhibited high
p-values, indicating a limited contribution to the model’s explanatory power. Consequently, a hypothesis test was conducted to evaluate the effect of omitting the indicators L3, NWC/A, and CA in 2020. A likelihood ratio test comparing the reduced model, including only the indicators size, VI/A, and ROA in 2020, and CA in 2022—with the full model confirmed that the predictive accuracy remained virtually unchanged. Therefore, the LR model can be effectively applied using only these three key indicators.
The applied hyperparameters of the ML models were selected based on prior experience from previous research (
Gavurova et al., 2022;
Letkovský et al., 2024) and recommendations provided by other authors (
Perez, 2006;
Kim & Kang, 2010;
Yoon & Kwon, 2010;
López Iturriaga & Sanz, 2015;
Thanh-Long & Hong-Chuong, 2022;
Sigrist & Leuenberger, 2023). Subsequently, the final configuration was fine-tuned empirically. When training the DT, a minimum of 20 observations was required for node splitting, and at least 7 observations were required for terminal nodes. The maximum iteration depth was set to 30. The SVM algorithm was configured with a linear kernel function, a termination tolerance of 0.001, and an insensitive loss function parameter (epsilon) of 0.01. To control the trade-off between margin maximization and classification error, the regularization parameter C (cost of constraint violation) was fixed at 1. For the ANN model, an MLP with an FF architecture was used, as it is one of the most common NN structures in predictive modeling and has demonstrated strong performance. The optimal configuration included three nodes in the hidden layer, balancing model simplicity and predictive power. Empirical experiments demonstrated that increasing the number of nodes did not improve accuracy and instead led to overfitting. Likewise, varying the number of hidden layers had little effect on predictive performance, as networks with a single hidden layer achieved accuracy comparable to those with multiple layers. This finding aligns with observations by Gavurová et al. (
Gavurova et al., 2022). The network architecture consisted of one input layer with seven nodes corresponding to the selected indicators and one output layer with a single node representing the binary classification (1 = bankrupt, 0 = healthy). The hyperbolic tangent function was used as the activation function. Although the BP learning algorithm is widely used in similar research (
Shin et al., 2005;
Tumpach et al., 2020;
Thanh-Long & Hong-Chuong, 2022;
Letkovský et al., 2024), the RPROP+ algorithm was employed in our study, as initial empirical experiments showed superior performance with this dataset. The effectiveness of different RPROP variants has been studied by
Igel and Hüsken (
2003), who identified iRPROP+ as the best-performing version. In this analysis, RPROP+ was preferred over BP due to its advantages in learning performance. Given the scope of the study, additional learning algorithms that might have marginally improved prediction accuracy were not explored in detail, although a general comparison of significance and accuracy was performed.
The issue of undetected bankruptcy probability can be partly attributed to the reduced quality of published financial data. The data used in this study were collected from publicly available financial statements, whose reliability may be limited due to both unintentional inaccuracies and deliberate manipulations by experienced financial managers (
Mućko & Adamczyk, 2023). Furthermore, financial statement analyses are based on historical cost accounting and, therefore, disregard the time value of money. This methodological limitation further decreases data quality and, consequently, the reliability of predictive models. Additionally, the dataset contains missing values. While some missing data points can be estimated or imputed, such procedures inevitably introduce uncertainty. Excluding all observations with at least one missing value would, however, significantly reduce the sample size, particularly affecting the already limited number of bankrupt firms. This exclusion approach has been employed in studies such as (
Hosaka, 2019;
Gavurova et al., 2022;
Andresson & Lukason, 2024;
Letkovský et al., 2024), whereas others, including (
Calabrese, 2023;
López Iturriaga & Sanz, 2015;
Wei et al., 2024;
Pereira et al., 2016), opted for value imputation. To preserve an adequate sample quality, this study did not employ missing value imputation. Another challenge was the inability to adequately incorporate enterprise size as a variable. In most cases, data on the number of employees were either unavailable or outdated. As a result, firm size was approximated using total assets as a proxy variable. The potential benefits of incorporating qualitative data in bankruptcy prediction have been demonstrated by several studies (
Karas & Režňáková, 2021;
Korol & Fotiadis, 2022;
Kaleem et al., 2024;
Wei et al., 2024;
Tobback et al., 2017;
Arcuri & Levratto, 2020;
Kwon & Lee, 2018;
Asgarnezhad Nouri & Soltani, 2016). However, access to qualitative data remains a significant barrier in our context, as such data are available for only a limited number of firms. This limitation necessitates a primary focus on quantitative indicators. As a compromise, two qualitative variables—industry sector and firm size—were included. Nevertheless, sector affiliation demonstrated minimal explanatory power regarding the dependent variable. Given the categorical nature of the sector variables, the machine learning test revealed that it possessed virtually no explanatory power, and its contribution to the prediction performance was negligible or non-existent. Consequently, this variable was excluded from the subsequent models, as it was considered redundant and unnecessary for improving predictive accuracy. Firm size, when calculated using asset size, effectively becomes a quantitative measure, the quality of which remains low. If actual firm-level data (e.g., employee counts) were available, this variable would likely be of higher quality and could reduce uncertainty in the analysis; however, obtaining such information was not possible in our study. Furthermore, the usefulness of size and sector is constrained by the fact that the sample consists exclusively of SMEs, where variability in these characteristics is relatively small. A higher contribution of these variables could be expected if the dataset included large enterprises and corporations.
The application of a data reduction method presents both advantages and disadvantages. One of its principal benefits is the balancing of the dataset, which enables the models to focus more effectively on the minority class (bankrupt firms). The substantial reduction in dataset size also shortens the training time of machine learning models and lowers computational demands. Furthermore, redundant information arising from highly correlated observations may be partially eliminated. However, this approach also entails certain risks. The omission of samples may result in the loss of valuable information that reflects real-world conditions. Such information loss may reduce the model’s ability to generalize its learned patterns when applied to new data. Additionally, random selection may decrease the representativeness of the sample. This risk could be mitigated by employing more sophisticated, strategically designed sampling techniques rather than purely random selection methods.
Table 12 presents a summary of important decisions in the research process.
5. Conclusions
Business risk assessment is an essential aspect of financial management, both for companies that need to continuously monitor their financial health to prevent crises and remain attractive to investors and for creditors who must make informed investment decisions. Different predictive methods are often comparable, making it essential not to rely on a single model but to validate predictions across multiple approaches to minimize the risk of misinterpretation.
The results indicate that effective predictive models can be developed using crisis-period data in a manner similar to standard periods. LR proves to be a reliable prediction method, maintaining comparable accuracy to AI techniques even during a crisis, without a significant decline in performance. This study focused on ML models—SVMs, NNs, and DTs—within the specific context of Slovakia, using a sample of SMEs during a period still influenced by the effects of COVID-19. The accuracy of these models was compared with LR, which, although a solid method, exhibited the lowest predictive accuracy. However, the differences between the models were not substantial enough to establish clear superiority. These findings suggest that ML models possess slightly higher potential for bankruptcy prediction than LR, though the difference in accuracy is modest, indicating room for further improvement. Given the scope of this study, not all ML approaches, such as RF or k-nearest neighbors (kNN), were explored.
The analysis did not reveal any distinct characteristics or vulnerabilities that could clearly indicate a forthcoming decline or provide management with an early warning to mitigate crisis impacts. Overall, the proposed models proved to be robust prediction tools, performing effectively not only under standard economic conditions but also during crisis periods.
One limitation of this study is the quality and scope of the dataset. The selection criteria included the number of employees, which many companies do not report, and a secondary criterion based on turnover or asset size. Additionally, only specific industries were included, limiting the applicability of the models to other sectors. Data quality is also a concern, as many companies fail to report even basic financial figures. The definition of bankruptcy used in the study serves as a theoretical framework but may not reflect actual business conditions; some companies meeting the defined criteria may continue operating and recover. Another limitation is the short two-year crisis period covered by the analysis, heavily influenced by the COVID-19 pandemic, as well as the two-year post-crisis period, which may make the results less representative of normal economic conditions.
Another limitation of this study concerns the configuration of the ML models. The hyperparameter search was conducted empirically, with parameter combinations selected according to their observed performance. Although this approach yielded satisfactory results, it does not guarantee identification of the global optimum. A more rigorous approach would involve a systematic exploration of the entire hyperparameter space (e.g., grid search or randomized search), which is computationally very demanding. Similarly, model validation was based on a single division of the dataset into training and testing subsets. For greater robustness and generalizability, multi-fold cross-validation would be preferable, as it repeatedly alternates validation subsets and produces an averaged performance estimate across multiple splits, thereby reducing the risk of sampling bias.
The selected crisis and immediate post-crisis period also represent an important limitation. The COVID-19 pandemic was an unprecedented economic shock, during which companies adopted extraordinary measures to ensure survival. Consequently, the quality and structure of publicly available financial data may have been more distorted than under normal market conditions. In addition, extensive state aid programs subsidized certain firms, temporarily preventing bankruptcies and altering natural market mechanisms. Such interventions may have weakened the relationship between financial distress indicators and actual bankruptcy events, potentially affecting the ability of the models to correctly identify distress patterns. In 2020, legislative measures (e.g., temporary moratoriums protecting debtors from bankruptcy proceedings) further influenced the observed outcomes. Moreover, external influences such as global market developments and foreign policy measures were not incorporated into the analysis, despite the fact that many companies operate internationally and are therefore directly or indirectly affected by cross-border economic conditions.
A major limitation of this study is the restricted access to qualitative data in the public conditions of the Slovak Republic. Financial indicators alone may not fully capture the true condition and prospects of companies. Prior research suggests that relying exclusively on financial variables may limit predictive performance, as the inclusion of qualitative information has been shown to enhance bankruptcy prediction accuracy. Future research should therefore consider incorporating additional variables such as the number of customers, order volumes, supplier relationships, management characteristics, and relevant macroeconomic indicators. A further limitation lies in the construction of the dataset through the application of random undersampling. While this approach helps to address class imbalance, it carries the risk of losing potentially valuable information and may not fully reflect real-world conditions. Future research should therefore consider more strategic sampling procedures or more sophisticated selection techniques, such as methods based on cluster centroids.
Additionally, the absence of verified information on the actual bankruptcy status of individual companies restricts the conclusions to a more theoretical level and limits the possibility of fully validating the predictive performance of the models.
Future research should apply the same methodology to different countries and industries, where higher-quality data may better reveal the real potential of ML in bankruptcy prediction. These results contribute to the literature by introducing AI-based models tailored to Slovakia’s SMEs and demonstrating that ML techniques provide high accuracy in bankruptcy estimation while maintaining stability compared with traditional statistical methods, such as LR.
One of the main contributions of this study is the development of bankruptcy detection models for SMEs in the Slovak industrial sector. These models have practical applications for financial managers and creditors and serve as valuable references for the academic community. The research further contributes through a comprehensive literature review on bankruptcy prediction and the implementation of the most frequently used methods within the context of Slovakia’s rapidly developing SME economy. Conducting this analysis during a period of economic crisis provides a meaningful benchmark for future comparisons in non-crisis conditions. From a scientific standpoint, examining models created during crisis periods is highly relevant, as key indicators may differ significantly from those observed in stable economic environments. This raises an important research question: do the key predictors identified during a crisis really differ from those in normal times? The study also contributes to the expansion of the knowledge base in financial management, with a notable aspect being the comparison of ML techniques with traditional LR. Both approaches yielded similarly strong results on the analyzed sample, supporting the view that LR remains a valid and effective prediction tool. These findings offer practitioners a practical and cost-efficient method to maintain competitiveness, enhance financial analysis, improve economic monitoring, and strengthen debt management.
This study focuses on two distinct periods: the crisis and the immediate post-crisis phase. By comparing predictive models under these specific conditions, the research contributes to a deeper understanding of bankruptcy detection across different economic environments. The sample analyzed originates from an economy predominantly composed of small and medium-sized enterprises, which may respond differently to crisis situations. On the one hand, SMEs tend to demonstrate greater flexibility and adaptability to rapidly changing conditions. On the other hand, they often lack sufficient capital resilience to withstand unexpected shocks. The study further contributes to the field of bankruptcy prediction by providing a literature review with a particular emphasis on SMEs, as well as empirical evidence on the application of LR and machine learning methods, achieving comparable levels of predictive accuracy. Moreover, it offers an empirical examination of the crisis period in the context of bankruptcy prediction and a subsequent comparison with the post-crisis period.
Future research should place greater emphasis on qualitative indicators and explore alternative sources of information beyond purely financial data. It would also be beneficial to expand the range of models to include additional ensemble techniques and to examine periods more distant from the crisis to assess the longer-term stability and robustness of predictive performance. Bankruptcy risk can be mitigated through proactive financial management, including careful monitoring of revenues and expenditures, increased operational efficiency, and effective communication with creditors. Furthermore, management is encouraged to draw upon research of this nature and to utilize predictive models as early warning tools for identifying potential financial difficulties at an early stage.