灾难会给青少年带来巨大的心理创伤，同时青少年也可以在灾难中获得成长。创伤后应激障碍(PTSD)和创伤后成长(PTG)是灾后青少年最常见的两种心理反应。共情作为个体与生俱来的能力可能会对幸存者创伤后心理反应产生影响。共情具有适应性的积极作用，可以帮助个体在创伤中获得成长。不过，在地震这种集体灾难背景下，共情能力更高的青少年更容易对他人遭受的苦难感同身受，具有更高的二次创伤暴露的风险，出现心理症状的可能性更大。本研究采用多批地震后青少年的追踪数据，分别从变量中心和个体中心的视角考察了共情对青少年PTSD和PTG的影响，共情对PTSD和PTG发展轨迹、轨迹类别的影响以及共情对PTSD和PTG潜在类别转换的影响。

研究一通过对汶川震后9.5、10.5年，雅安震后3.5、4.5年和九寨沟震后8、20个月青少年的调查，首先分析三个样本中第二个时间点PTSD和PTG的关系，之后分别用第一个时间点的共情总分及各维度预测后一个时间点的PTSD和PTG。结果发现，PTSD和PTG在不同样本中均不存在显著相关。不同样本中共情对PTSD和PTG的预测作用基本一致，表现为共情总分同时正向预测PTSD和PTG；幻想和个人忧伤对PTSD具有显著的正向预测作用，对PTG的预测作用不显著；观点采择对PTSD具有显著的负向预测作用，对PTG具有显著的正向预测作用；共情关注仅对PTG具有显著的正向预测作用。研究一发现了共情在灾害青少年群体的双刃剑效应，具体来说，幻想和个人忧伤主要发挥消极作用，观点采择和共情关注主要发挥积极作用。

不同于研究一只关注PTSD和PTG在同一时间点的关系，研究二以雅安震后3.5、4.5、5.5和6.5年的青少年为被试，进一步考察了PTSD和PTG随时间变化的发展趋势及共情的预测作用。分别采用交叉滞后模型和多元潜变量增长模型对PTSD和PTG在时间历程中的关系进行分析。结果发现，PTSD和PTG在时间历程上不存在相互预测的关系，两者的发展相互独立。PTSD初始水平较低，PTG初始水平较高；随着时间的发展，青少年的PTSD逐渐降低，PTG逐渐升高。PTSD和PTG的初始值和发展速率存在显著的个体差异。高幻想和个人忧伤的青少年PTSD初始值较高，高观点采择和共情关注的青少年PTSD初始值较低、PTG初始值较高；高幻想和个人忧伤的青少年PTSD随时间下降的速率较慢，高观点采择和共情关注的青少年PTG随时间增长的速率较快。

基于研究二发现的PTSD和PTG的初始值和发展速率存在显著个体差异这一结果，研究三进一步采用潜变量混合增长模型从个体中心的视角分别考察了PTSD和PTG在个体层面发展轨迹的类别，并分析共情各维度对不同类别的影响。结果发现，PTSD的发展轨迹存在三种类别，分别是心理弹性组、心理康复组和长期受损组；PTG的发展轨迹也存在三种类别，分别是高成长稳定组、中成长上升组和低成长稳定组。在PTSD发展轨迹的类别归属上，相较于心理弹性组，高幻想和个人忧伤的青少年更大概率属于长期受损组；相较于心理康复组，高幻想的青少年更大概率属于长期受损组；相较于心理弹性组，高个人忧伤的青少年更大概率属于心理康复组。在PTG发展轨迹的类别归属上，相较于低成长稳定组，高观点采择和共情关注的青少年更大概率属于高成长稳定组；相较于中成长上升组，高共情关注的青少年更大概率属于高成长稳定组；相较于中成长上升组，高观点采择的青少年更大概率属于低成长稳定组。

在分别考察了PTSD和PTG发展轨迹的亚类别后，有必要同时关注个体层面PTSD和PTG关系的类别及类别随时间的转换。研究四首先采用潜在剖面分析将每个时间点的被试都根据PTSD和PTG的共存特征分为了成长组、低反应组和症状-成长共存组等三个类别。进一步采用潜在转换分析考察个体类别的转换特征，发现青少年群体可分为稳定成长型、积极转换型、稳定低反应型和消极转换型等四种转换类型。相较于积极转换型、稳定低反应型和稳定成长型，幻想和个人忧伤水平高的青少年更大概率属于消极转换型；相较于稳定成长型，观点采择水平低的青少年更大概率属于消极转换型；相较于积极转换型，个人忧伤水平低、观点采择水平高的青少年更大概率属于稳定成长型；相较于稳定低反应型，观点采择和共情关注水平高的青少年更大概率属于稳定成长型；相较于稳定低反应型，共情关注水平高的青少年更大概率属于积极转换型。

通过上述四项研究可以发现，PTSD和PTG表现为相互独立的关系，群体层面上两者在横断和纵向上都不存在显著的关系，个体层面上PTSD和PTG的发展轨迹均可分为三种类别(PTSD：心理弹性组、心理康复组、长期受损组；PTG：高成长稳定组，中成长上升组、低成长稳定组)，各个时间点PTSD和PTG的关系可分为三种类别(成长组、低反应组、症状-成长共存组)，个体所在类别随时间的发展特征可分为四种类型(稳定成长型、积极转换型、稳定低反应型、消极转换型)。共情对灾后青少年创伤后心理反应存在双刃剑作用，幻想和个人忧伤主要发挥消极作用，观点采择和共情关注主要发挥积极作用。

Natural disaster, including earthquake, is one type of traumatic events that can trigger intensive fear. The psychological reactions following traumatic events include negative as well as positive reactions, such as posttraumatic stress disorder (PTSD) and posttraumatic growth (PTG).

Empathy refers to the trait tendencies of a person to both affectively experience emotions of concern at the suffering of others and to cognitively adopt the perspective of another. After the occurrence of natural disasters, individuals with high empathy are more vulnerable to the adverse environment around them and the traumatic situation of others, resulting in greater psychological pressure and fear, and these pressures and negative emotions will force individuals to think about the meaning of trauma, thus promoting the generation of PTG. However, in the context of a collective disaster such as the earthquake, individuals with high empathy are more likely to empathize with the sufferings of others, and thus have a higher risk of secondary trauma exposure, which may have a negative impact on the mental health of adolescents after the disaster. Moreover, empathy has different components such as emotional and cognitive components according to the relevant theories about empathy. Once individuals have empathy with others, then these components will be activated, and in turn results of PTSD or PTG.

The current study examined the effects of empathy on PTSD and PTG in adolescents and the mechanisms were investigated from the perspectives of variable center and individual center, the effects of empathy on the developmental trajectories and categories of PTSD and PTG, and the effects of empathy on the transformation of latent categories of PTSD and PTG.

Study 1 by means of the investigation of the adolescents in 9.5 and 10.5 years after the Wenchuan earthquake, 3.5 and 4.5 years after the Ya 'an earthquake and 8 and 20 months after the Jiuzhaigou earthquake, the structural equation model was established based on three batches of tracking data to investigate the relationship between PTSD and PTG in different samples, and analyze the direct effect of PTSD and PTG from empathy and four dimensions. The results showed that empathy predicted PTSD and PTG in the same way in different samples of tracking data. The total score of empathy positively predicted both PTSD and PTG. Fantasy and personal distress had significant positive effect on PTSD, but no significant effect on PTG. Perspective taking and empathic concern had significant positive effect on PTG, perspective taking had significant negative effect on PTSD, empathic concern had no significant effect on PTSD, and there was no significant correlation between PTSD and PTG. Study 1 found the double-edged sword effect of empathy, indicating that fantasy and personal sadness mainly played a negative role, while the perspective taking and empathic concern played a positive role.

Study 2 examined the developmental trends of PTSD and PTG over time and the predictive of empathy among 3.5, 4.5, 5.5 and 6.5 years after the Ya 'an earthquake. The results showed that, from the group level, the initial value of PTSD was lower, and the initial value of PTG was higher. Over time, PTSD levels decrease and PTG levels increase. There were significant individual differences in the initial value and development rate of PTSD and PTG, and there was no correlation between PTSD and PTG over time. Adolescents with high fantasy and personal distress had higher initial PTSD, while adolescents with high perspective taking and empathic concern had lower initial PTSD and higher initial PTG. Adolescents with high fantasy and personal distress had a slower rate of decrease in PTSD over time, while adolescents with high perspective taking and empathic concern had a faster rate of increase in PTG over time

Study 3 further examined the categories of the developmental trajectories of PTSD and PTG at the individual level from the perspective of individual center, and analyzed the influence of empathy dimensions on the category of individual affiliation. It was found that there were three types of development trajectories of PTSD, namely resilience group, rehabilitation group and long-term impairment group. There are also three types of development trajectories of PTG, namely, the high-growth stable group, the medium growth ascending group and the low growth stable group. In the category of the trajectory of PTSD, adolescents with high levels of fantasy and personal distress were more likely to be in the long-term impairment group than those in the resilience group. Compared with the rehabilitation group, the adolescents with high fantasy were more likely to belong to the long-term impairment group. Compared with the resilience group, adolescents with high personal distress were more likely to belong to the recovery group. In the category of PTG development trajectory, compared with the low growth stable group, adolescents with high perspective taking and empathic concern are more likely to belong to the high growth stable group. Compared with the low growth group, the adolescents with high empathic concern were more likely to belong to the high growth stable group. Compared with the medium growth ascending group, the adolescents with high perspective taking were more likely to belong to the low growth stable group

Study 4 used latent profile analysis to classify participants at each time into three categories based on the coexistence characteristics of PTSD and PTG: growth group, low psychological reaction group, and symptom-growth coexistence group. Furthermore, latent transition analysis was used to investigate the transformation characteristics of individual categories, and it was found that the adolescent group could be divided into four transformation types: stable growth type, positive transformation type, stable low psychological reaction type and negative transformation type. Compared with the positive transformation type, the adolescents with low personal distress and high perspective taking are more likely to belong to the stable growth type. Compared with the stable low psychological reaction type, the adolescents with high perspective taking and empathic concern are more likely to belong to the stable growth type. Compared with the negative transformation type, the adolescents with low fantasy, personal distress and high perspective taking are more likely to belong to the stable growth type. Adolescents with high fantasy and personal distress were more likely to be in the negative transformation category than those with positive transformation and stable low psychological reaction types. Compared with the stable low psychological reaction type, the adolescents with high e empathic concern are more likely to belong to the positive transformation type.