Introduction

Individuals encounter both positive and negative situations throughout their lives that shape their experiences. Natural disasters such as earthquakes, floods, and storms can pose threats to individuals’ mental health as well as their physical health. It can lead to traumatic experiences that endanger individuals’ psychological balance and general integrity of life. As a result of a traumatic experience, individuals’ assumptions about life may be disrupted1,2. Individuals exposed to earthquakes often experience psychological trauma, significantly impairing their quality of life3. People of all ages, particularly children and adolescents, are adversely affected by earthquakes4.

Common traumatic responses observed in earthquake survivors include shock, persistent fear and anxiety, difficulty concentrating, sleep disturbances, grief, anger, panic, and hopelessness5,6. Among children, emotional and behavioral reactions include reluctance to separate from their parents, fear of death, frequent questioning about earthquakes, unwillingness to return home, irritability, difficulty controlling anger, sleep disturbances, and loss of appetite7.

However, not all people exposed to traumatic events exhibit the same stress responses. Most people exhibit varying levels of adjustment when exposed to traumatic events. The positive personal changes elicited by trauma-related stressors, a phenomenon known as post-traumatic growth (PTG)8. The PTG model9 has been developed based on growing empirical research and clinical experience.

According to the PTG model, a traumatic life event occurs that disrupts an individual’s level of functioning, and this event is at a level that significantly disrupts the person’s assumptions or core beliefs about the world10. The individual whose assumptions are challenged is forced to restructure their cognitive systems11. Subsequently, two distinct cognitive processing processes occur: intrusive and deliberate rumination. Intrusive rumination occurs as an automatic, uncontrollable thought that often contains unpleasant content, while deliberate rumination occurs as constructive thoughts that involve attempts to give meaning to personal experiences9,11. The positive effect of deliberate rumination on PTG has often been reported. Furthermore, as cognitive processes progress to more conscious forms, levels of distress can motivate individuals to work toward an understanding12,13. The next stage in the PTG model is self-disclosure. For PTG to occur, the individual must perceive self-disclosure as beneficial. If an individual realizes that their self-disclosure is well-received by others, this can create an emotional bond and help manage emotional distress9,14. Finally, the individual reaches the stage of ‘acceptance of a changed world’, which is one step before PTG. According to9, PTG is associated with a sense of wisdom reflected not in simple measurements of overall happiness or depression, but in a new narrative that acknowledges the complexity of the world.

According to the PTG model, growth is a gradual outcome following traumatic events rather than a coping mechanism15,16. PTG consists of the subdimensions of new possibilities, relating to others, personal strength, spiritual change, and appreciation of life17. New possibilities refers to recognizing that new possibilities and opportunities exist in life, identifying new interests and new paths. Relating to others indicates a willingness and effort to establish more meaningful and deep intimate relationships. Personal strength is related to the perception of self-confidence and the ability to cope with stressful situations in the future. The individual realizes they have more self-confidence than they thought. Spiritual change refers to questioning beliefs along with existential questions and developing a stronger spiritual structure. Finally, appreciation of life refers to valuing the small things in life that may have gone unnoticed before the trauma. In this stage, the individual appreciates the value of their own life and appreciates the value of each day17,18. Related research shows that individuals who experience PTG experience positive changes such as existential growth, lessons learned from illness, new opportunities, and social growth. They have a greater appreciation for survival, set new goals, improve their relationships, and have greater awareness of their personal development and health8,16,19,20. When the predictors of PTG are examined, it is observed that it has significant relationships with various psychological constructs. PTG is positively associated with perceived social support21, mindfulness13, self-compassion, and psychological flexibility22,23, while negatively associated with anxiety-depression24, rumination (repetitive thinking)25 and psychological inflexibility26.

Psychological inflexibility and post-traumatic growth

Psychological inflexibility is described as “the rigid dominance of psychological reactions, over chosen values and contingencies, in guiding action”27. In other words, psychological inflexibility refers to the inability to interact harmoniously with the present moment28. Psychological inflexibility is a central concept in Acceptance and Commitment Therapy (ACT), and ACT aims to reduce psychological inflexibility29. The components of PTG emphasize awareness of thoughts and feelings, acceptance of life’s ordinary course, and building a value-based life. However, psychological inflexibility can play an inhibitory role in PTG22,30.

Psychological inflexibility makes it difficult to focus on the here and now31. So that individuals may experience less growth when they shape their sense of self by their trauma history and ignore important aspects of the self. Considering the negative relationship between psychological inflexibility and PTG32, reducing psychological inflexibility may help contextualize the self by facilitating the distancing of trauma from the self33,34. Individuals with high levels of psychological inflexibility have difficulty confronting internal experiences such as emotions, thoughts, and bodily sensations without judgment or defense, and taking actions that are consistent with personal values31. Increasing psychological flexibility can make the way an individual responds to a traumatic event healthier when exposed to it. It is important to reduce or prevent negative psychological effects that may occur after a traumatic event. Understanding the role of psychological inflexibility in traumatic stress and PTG levels can help improve mental health16.

Psychological inflexibility and intolerance of uncertainty (IU)

Intolerance of uncertainty refers to the perception of uncertainty as negative and unacceptable. People who are intolerant of uncertainty consider the possibility of a negative life event occurring unacceptable, regardless of its probability of occurrence35. IU involves beliefs that uncertain situations will produce negative outcomes and that the consequences cannot be managed36. IU is considered as a core component of worry and anxiety-related pathologies37,38,39,40. According to35, who developed an instrument (IUS) to determine the level of IU, IU has two factors, which are named prospective anxiety and inhibitory anxiety. Prospective anxiety (e.g., cognitive)41. Refers to anticipatory anxiety42 involving the inability to tolerate uncertainty about future events, while inhibitory anxiety (e.g., behavioral) refers to functional impairments resulting from uncertainty about future events41. IU is expanded by the Extended Transdiagnostic Model (ETM) by addressing prospective anxiety and inhibitory anxiety through the facets “need for predictability” and “uncertainty arousal.”

According to the Extended Transdiagnostic Model (ETM) of IU. When an individual encounters an uncertain situation, they make a threat esmiate43. If threat expectancy is low, they may not experience any arousal despite the presence of uncertainty. However, if the uncertainty is within the individual’s realm of high sensitivity, threat estimate may activate emotional arousal (e.g., the threat of an inability to regulate emotion for a psychologically inflexible individual). The individual compares what is perceived (actual events) with what is wanted (expected events), and if there is a discrepancy, emotional arousal occurs to resolve the discrepancy. Emotional arousal triggers a need for predictability. If the need for predictability is high, a second level of arousal emerges. This arousal is distressing and leads to a variety of dysfunctional behaviors in the long term (e.g., safety-seeking behaviors, compulsions). If the need for predictability is low, individuals recognize numerous possibilities regarding the current situation. They maintain a standby state of threat estimate. They demonstrate patience, accepting that the situation involving uncertainty will not be resolved quickly. Individuals reexamine their goals and begin to reorganize their behavior according to new possibilities43.

The ETM model of IU emphasized the individual’s perceptions of uncertain situations and the process of evaluating the problem situation43. Given that most problems inherently contain some uncertainty, the problem-solving process of an intolerant person may be affected44. Individuals with high levels of IU struggle with feelings of helplessness45. Emotion regulation as an important predictor of PTG46 is negatively affected by IU47. So IU may cause the problem to become unnecessarily worse44, and a decrease in the level of psychological well-being48. Higher levels of psychological inflexibility and intolerance to uncertainty predict lower levels of psychological well-being49.

Individuals high in psychological inflexibility have difficulty accepting their negative emotions as they are50, and tend to have a lower tolerance for uncertainty51. Individuals lacking flexibility in the face of experience struggle to manage uncertain situations52. People with IU may be trying to avoid the evocation of threatening mental images and the uncomfortable bodily arousal that accompanies these images44. For example, people with high IU use more of the maladaptive strategy of cognitive avoidance53, which promotes anxiety and stress44. Indeed, psychological inflexibility and intolerance of uncertainty are both predictors of posttraumatic stress symptoms54. Based on the mentioned research findings, we hypothesized (H2) that increased psychological flexibility would expand the capacity to tolerate uncertainty. In line with the H3, exploring the mediating role of intolerance of uncertainty between psychological inflexibility and PTG may facilitate understanding of the factors that play a role in the development of PTG.

The mediating role of intolerance of uncertainty

Individuals with high levels of intolerance of uncertainty perceive uncertain situations as a threat55. According to the ACT, individuals may encounter challenging life events such as natural disasters, financial hardship, interpersonal difficulties, illness, separation, and death as part of being alive50. Psychologically inflexible individuals may have a compulsive need for predictability when faced with adverse situations43. When individuals need a high level of predictability in uncertain situations, they may struggle to exert attentional control over their environment, reflect on their goals, and organize and utilize adaptive coping behaviors (e.g., emotion regulation43,47,56.

The behavioral characteristics of IU are indicative of PI symptoms. PI weakens an individual’s ability to stay present57. Lack of Ability to contact with the present moment may lead to avoidance50 of trauma-related stimuli58. IU is a predictor of experiential avoidance, which is a key component of psychological inflexibility47,59. Increased IU triggers the overuse of rigid strategies and narrows one’s behavioral alternatives and possibilities for positive experiences28,60. When IU pressure decreases61, through the cultivation of experiences, traumatized individuals can begin to remain in contact with distressing experiences and learn to interpret them in more in a more functional way58. Indeed, these outcomes fall within the scope of PTG dimensions. Acceptance of trauma-related stimuli as they are and the resulting decrease in experiential avoidance may promote the development of PTG. In this context, considering evidence that intolerance of uncertainty is positively related to psychological inflexibility and negatively related to post-traumatic growth32,45,62, we assumed that intolerance of uncertainty has a mediating role on the relationship between psychological inflexibility and post-traumatic growth.

Aims

Given that adolescence is a period of significant biological and psychological change, adolescents’ sensitivity to traumatic experiences should be considered63,64. Traumatic experiences during adolescence can lead to developmental differences associated with post-traumatic growth15. Trauma-focused studies on adolescents may provide evidence for the development of PTG in adolescents. Indeed, adolescents are better at finding meaning, empowering themselves, and embracing new possibilities65. Furthermore, given that adolescence is a critical period for identity formation, traumatic experiences can play a significant role in shaping adolescents’ identity development processes66,67. Adolescents’ traumatic experiences can serve as a transformation factor in their post-traumatic growth and influence their ability to reconstruct their identity through changes in perspective, acquiring new beliefs, or setting personal goals68.

A literature review reveals limited research on posttraumatic growth in adolescents. Studies examining variables such as psychological inflexibility and intolerance of uncertainty in adolescents are particularly scarce. In this context, the lack of research integrating PI and IU with earthquake-related trauma highlights the need for further research in this area. This study aimed to examine the posttraumatic growth levels and PI and IU levels of individuals affected by earthquakes. The present study examines the mediation role of intolerance of uncertainty in the relationship between psychological inflexibility and post-traumatic growth. The following hypotheses (Hs) were examined:

  • H1: Psychological inflexibility has a positive relationship with intolerance of uncertainty.

  • H2: Psychological inflexibility has a negative relationship with post-traumatic growth.

  • H3: Intolerance of uncertainty has a mediating role in the relationship between psychological inflexibility and post-traumatic growth.

Methods

Research design

A correlational research design was utilized to examine if there was a relationship among the level of psychological inflexibility, intolerance of uncertainty, and post-traumatic growth. The correlational research model is employed to determine whether a relationship exists between two or more variables or to assess the level of such a relationship69. Based on this approach, the present study examines the levels of post-traumatic growth among high school students who experienced the 7.8 and 7.5 magnitude earthquakes that struck Kahramanmaraş on February 6, 2023. Specifically, the study examines post-traumatic growth in relation to intolerance of uncertainty, psychological inflexibility.

Participants

The study sample consists of a total of 399 individuals, with ages ranging from 14 to 18. 225 (56.4%) of the participants were female, and 174 (43.6%) were male. The number of individuals who lost a close relative in the earthquake is recorded as 146 (36.6%), while those who did not lose a close relative account for 253 (63.4%).

Measures

Post-traumatic Growth Inventory (PTGI)

The PTGI was used to measure the level of positive change and transformation in participants’ lives following their exposure to earthquake trauma. Developed17 the PTGI consists of 21 items and is a Likert-type scale, scored on a 0 to 5 scale, with a total score range of 0 to 105. Higher scores indicate greater levels of PTG. Reported the internal consistency of the original scale as α = 0.90, with subscale internal consistency coefficients ranging from α = 0.67 to α = 0.8517. The test-retest reliability coefficient was reported as 0.71. The Turkish adaptation of the scale was conducted by70, who found a Cronbach’s alpha coefficient of α = 0.93 for the entire scale. Construct validity was tested through factor analysis, which identified a five-factor structure as the most appropriate. In this five-factor model, 15 out of 21 items were found to load onto the same factors as in the original scale, and the model explained 67% of the total variance.

Intolerance of Uncertainty Scale (IUS-12)

IUS-12 was used to assess participants’ levels of intolerance toward uncertainty. The IUS-12 was developed by35 and adapted into Turkish by71. The scale consists of 12 items, is a Likert-type scale with five response options, and includes two subdimensions. The overall internal consistency coefficient of the scale was reported as 0.88, while the internal consistency coefficients for the prospective anxiety subdimension and inhibitory anxiety subdimension were 0.84 and 0.77, respectively. Found the Cronbach’s alpha reliability coefficient for the entire scale to be 0.84, with subscale reliability coefficients of 0.83 for inhibitory anxiety and 0.75 for prospective anxiety71.

Acceptance and Action Questionnaire-II (AAQ-II)

The AAQ-II was used in this study to measure participants’ levels of psychological inflexibility. The AAQ-II was originally developed by72 to assess individuals’ psychological flexibility. The original version of the scale consisted of 16 items, where higher scores indicated lower psychological flexibility and higher psychological inflexibility. Due to its high internal consistency, the scale was revised into a 7-item version, scored on a 7-point Likert scale. The test-retest reliability of the scale over a 60-day interval was reported as 0.81. The Turkish adaptation of the scale was conducted by73. The scale is unidimensional, and the Cronbach’s alpha internal consistency coefficient was calculated as 0.84.

The personal information form

This form, prepared by the researcher, includes items regarding the participants’ status of being in the earthquake zone during the earthquake, whether they lost a close relative in the earthquake, as well as their age and gender information.

Procedure

The data were collected from participants using the convenience sampling method. Convenience sampling is primarily employed to minimize cost, time, and labor loss74. The instruments were administered to high school students studying in the Onikişubat district of Kahramanmaraş during the 2023–2024 academic year in Turkey.

Prior to data collection, all necessary administrative and ethical approvals were obtained. The participants were informed in detail about the scope, purpose, and significance of the study, with particular emphasis placed on confidentiality and voluntary participation. The data were collected face-to-face from participants. The data will be stored by the researcher for five years. Additionally, the SPSS files containing the study data will be preserved both digitally and by the researcher in physical form for the same duration.

Data analysis

The data were analyzed using the SPSS 29.0 statistical software package. The findings were evaluated based on a 95% confidence interval and a 0.05 significance level. Initially, the dataset was reviewed to assess its statistical suitability. Since the data were collected face-to-face, a missing data analysis was conducted. Subsequently, outlier detection was performed using the Mahalanobis distance method, and as a result of these analyses, 19 outliers were removed from the dataset. Pearson Correlation Analysis was performed to test hypotheses H1 and H2. A mediation analysis was performed to test the mediating role of intolerance of uncertainty in the relationship between post-traumatic growth and psychological inflexibility (H3). The mediation analysis was performed using Process Macro, a statistical tool developed by Andrew F. Hayes that enables testing of multiple sequential mediation models and conditional effects based on regression analysis75. Furthermore, the Bootstrap technique was applied to ensure the reliability and validity of the mediation model76. Using this technique, the indirect effect of intolerance of uncertainty on post-traumatic growth was examined within the proposed mediation model.

Results

Descriptive statistics

The Pearson Correlation Analysis was performed to examine the relationship between post-traumatic growth, intolerance of uncertainty, and psychological inflexibility. The normality of the dataset was examined by utilizing skewness and kurtosis values, and the findings were presented in Table 1.

Table 1 Descriptive statistics and test results for the normality assumption.
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As shown in Table 1, the skewness values of the variables range between − 0.281 and 0.189, while the kurtosis values vary between − 0.724 and 0.557. Given that all variables have skewness and kurtosis coefficients within the acceptable range of -1 to + 1, the dataset meets the normal distribution assumption. According to77, for social sciences, skewness and kurtosis values falling between − 1 and + 1 at a 0.05 significance level indicate an acceptable normal distribution. Therefore, the skewness and kurtosis coefficients in this study confirm the normality assumption.

Testing the H1 and H2

Hypotheses H1 and H2 were tested with Pearson Correlation Analysis, and the findings were presented in Table 2.

Table 2 Correlation analysis results.
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According to the results of the Pearson Correlation Analysis, a moderate negative correlation was found between post-traumatic growth and intolerance of uncertainty (r = -0.468). Another significant finding revealed a moderate negative correlation between post-traumatic growth and psychological inflexibility (r = -0.415). Furthermore, a moderate positive correlation was observed between psychological inflexibility and intolerance of uncertainty (r = 0.552). These statistical findings showed that hypotheses H1 and H2 were confirmed. However, no statistically significant relationship was found between the age variable and the other variables.

Testing the H3: Mediation analysis

The Process Macro developed by Andrew F. Hayes was utilized to test the H3, employing Model 4. In the regression analysis, the Bootstrap method was applied. In this context, psychological inflexibility (X) was defined as the independent variable, post-traumatic growth (Y) as the dependent variable, and intolerance of uncertainty (M) as the mediating variable. The findings of the analysis were presented in Fig. 1; Table 3.

Table 3 Findings on the mediating role of intolerance of uncertainty in the relationship between post-traumatic growth and psychological inflexibility.
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Table 3 shows the regression analysis results showing the effect of intolerance of uncertainty (M) as a mediator variable in the relationship between psychological inflexibility (X) and post-traumatic growth (Y). According to the table, psychological inflexibility positively predicted intolerance of uncertainty (β = 0.410; t = 13.197; p < 0.05). Moreover, psychological inflexibility negatively predicted post-traumatic growth (β = -0.344; t = -9.079; p < 0.05). Additionally, intolerance of uncertainty was found to negatively predict post-traumatic growth (β = -0.710; t = -6.61; p < 0.05).

Fig. 1
figure 1

The Mediating Role of Intolerance of Uncertainty in the Relationship Between Post-Traumatic Growth and Psychological Inflexibility (Model 4) Accordingly. when the indirect effect of the mediating variable, (M) within the 95% confidence interval was evaluated, the results for intolerance of uncertainty were BootLLCI intolerance of uncertainty = -0.402 and BootULCI intolerance of uncertainty = -0.183. Considering that the lower, (BootLLCI) and upper, (BootULCI) bounds of the bootstrap results fall within the 95% confidence interval and both are below zero, it can be concluded that intolerance of uncertainty has a statistically significant mediating role in the proposed model. When the fully standardized effect size of the mediation role is examined, (K2 intolerance of uncertainty = -0.291), intolerance of uncertainty was found to have a partial mediating role. The schematic representation of Model 4 is presented in Fig. 1.

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Discussion

The idea of “post-traumatic growth” focuses on the potential positive outcomes of trauma78. PTG explains pozitive transformation following trauma. In the current study, we aimed to examine the PTG levels of high school students exposed to the Kahramanmaraş earthquake, which resulted in a major trauma, in the context of the relationship between PTG and psychological inflexibility and Intolerance of Uncertainty. According to the findings, there are significant relationships among psychological inflexibility, intolerance of uncertainty, and post-traumatic growth. The findings are explained in terms of the research hypothesis.

The first hypothesis of the study (H1) suggested that there is a positive relationship between psychological inflexibility (PI) and intolerance of uncertainty (IU). Findings revealed that there is a significantly positive relationship between PI and IU. Therefore, H1 was supported by findings. This finding is consistent with previous studies79,80,81. Psychological inflexibility is defined in the literature as the opposite of psychological flexibility50, and studies supporting the negative relationship between psychological flexibility and intolerance of uncertainty50 are consistent with the present findings. Indeed, PI is a predictor of IU82, PI and IU are both predictors of mental health outcomes52. According to the findings of our study, PI and IU may serve as risk factors for PTG. Indeed, our study revealed that changes in intolerance of uncertainty in earthquake-exposed individuals are related to changes in psychological inflexibility.

The second hypothesis of the study (H2) suggested that a positive relationship between psychological inflexibility and post-traumatic growth. In consistent with H2, we found a negative relationship between PI and PTG. This finding aligns with previous research findings16,32,91. Findings of our study also align with studies26,68, which emphasized that post-traumatic growth is positively associated with effective coping skills, psychological resilience, sources of social support, and a positive attitude. In one study, Psychological flexibility has been determined to predict post-traumatic growth23. Indeed, higher PI levels allow individuals to show fewer symptoms of stress and experience greater growth after trauma16.

The third hypothesis of the study (H3) suggested that intolerance of uncertainty mediates the relationship between psychological inflexibility and post-traumatic growth. In consistent with H2, the findings showed that IU had a partial mediating role in the relationship between PI and PTG. Our findings are consistent with the findings of studies showing a relationship with outcomes that may affect the development of PTG, although not directly with PTG. There are research findings showing that IU has a mediating role in the relationship between various psychological structures related to mental health. For example, IU has a mediation role in the relationship between psychological inflexibility and social-distancing phobia82, worry and psychological distress83; fear of COVID-19 and positivity84. In one study, IU has been associated with worry85, and post-traumatic symptoms86. Our research findings suggested that IU should be taken into consideration alongside PI when explaining PTG. When evaluated together with previous research findings, it would not be wrong to say that IU is a risk factor for PTG. So, determining the mediating role of intolerance of uncertainty provides a theoretical contribution to a better understanding of the relationship between PI and PTG.

Strengths, future research and limitations

Potentially traumatic events may lead to the development of a wide range of negative psychological reactions87 such as difficulty in emotion regulation, poor sleep quality88, attention deficit89 and decreased academic performance90 in addition to general post-traumatic stress disorder (PTSD) symptoms. Examining the factors associated with PTG can provide us with a background for coping with the effects of potential trauma. This study demonstrated that IU mediated the connection between PI and PTG in high school students who experienced a major earthquake trauma. Mental health professionals can adopt current research findings through ACT based counselling and psychoeducation to utilize them to address psychological problems and enhance well-being. Indeed, despite trauma-exposed students’ negative post-traumatic cognitions, ACT has been shown to promote value-based behaviors by reducing experiential avoidance16,91. ACT’s intervention targets the reduction of psychological inflexibility. In ACT treatment, interventions based on psychological flexibility mitigating intolerance of uncertainty seem possible79. Besides ACT-based interventions, examining IU according to the MET model through empirical research will further enhance our understanding of how IU functions to facilitate the development and maintenance of PTG. Furthermore, providing training in schools on other personal factors (e.g., self-efficacy)92,93 that buffer against the potential consequences of traumatic events94 may positively affect the development of PTG.

The current study is concerned with a current, concrete event. It explores the factors associated with the PTG of students exposed to a real-life event such as an earthquake. In addition to the theoretical contributions of the current research, the fact that the data were collected face-to-face can be considered an advantage. Face-to-face survey may help overcome shortcomings of online data collection such as lower response rates, sampling-related bias, quality, and security of data95,96. The researcher collected the data via face-to-face survey from high school students in the city where the earthquake occurred. Collecting data face-to-face about an earthquake, which is a severe traumatic event, can help reduce data loss. Participants were informed before responding to the scales and if necessary, explanations were made during data collection. This effort may have positively impacted the validity of the current data.

There are several limitations of the current study that may provide further extension of the research. This study used a self-report questionnaire to collect data, and but self-reported data may not provide completely objective data. In future research, using the AAQ-II, IUS-12 and PTGI in observational and qualitative studies may reduce the limitations of self-report data. Besides, collecting data by contolling whether the participants received psychological support after the earthquake may differentiate the findings we obtain. The current data were obtained using a convenience sampling method. Data obtained from students who migrated from Kahramanmaraş and were not at school during data collection may affect the research results. Therefore, collecting data using a random sampling method may increase the measurement power of the tools and expand the scope of application of the findings. However, the cross-sectional nature of the current study means that we cannot generalize the results more broadly. Since the statistical sample of this study consists only of high school students in Kahramanmaraş province, we need to be very cautious in generalizing the results. Considering that adolescence is a period of transition and identity formation, we examined PTG in high school students. The relationship among PTG, PI, and IU may also be reexamined in adult and older samples.

Conclusion

Overall, we found that intolerance of uncertainty partially mediates the relationship between psychological inflexibility and post-traumatic growth. Higher levels of psychological inflexibility were related to higher levels of intolerance of uncertainty and post-traumatic growth. IU plays a dominant role in the progression of psychological disorders, and its connection with PI makes IU an important construct, especially from ACT perspective. Therefore, based on the results of the study, it is concluded that in the future, reducing individuals’ levels of intolerance of uncertainty and psychological inflexibility is essential for promoting post-traumatic growth. Finally, the picture painted by the results presented here may be interesting and inspiring for researchers who will examine the effects of potential traumatic events, for clinicians who will develop intervention plans to enhance PTG, and for general readers.