Self-Efficacy Scale.The study used an adapted version (Cumsille, Martínez, Rodriguez, & Darling, 2014) of the scale developed by Sherer et al. (1982) and Sherer and Adams (1983), which includes 6 items that evaluate SB (e.g., I can focus on a task and persist in doing it). The items are answered in a five-point Likert scale (1= does not describe me at all to 5= completely describes me). The score was computed by adding the 6 items together. Possible scores range from 6 to 30 points: the higher the score, the stronger the SB (α=.80).

Perceived Magnitude. This aspect was evaluated through 3 self-report questions about the perception of material consequences of the earthquake. The response format provides 4 or 5 alternatives (between 1 and 4 or 5), from no damage (e.g.,There was no damage to most of the nearby houses and buildings) to considerable damage (e.g.,Most constructions such as houses or buildings were destroyed). The score was computed by adding the 3 items together. Possible scores range from 3 to 14 points; the higher the score, the higher the perceived magnitude (α=.65).

Fear experienced during the earthquake. A 6-question scale was created, with questions that assessed the fear experienced during the earthquake (e.g., Did you think your life was in danger?), with dichotomous answers: 1= yes, 0=no. The total score was computed by adding the 6 items together. Possible scores range from 0 to 6 points; the higher the score, the more intense the fear during the earthquake (α=.77).

Post-traumatic stress scale. An adapted version of Davidson's scale (Davidson et al., 1997) was used, with 17 items which evaluate the frequency of PTSS experienced over the previous two weeks (e.g.,Do you feel anguish when there is an unexpected noise or an abrupt movement?). The responses could range from 1=never to 6=nearly every day. The total score was computed by adding the 17 items together. Possible scores range from 17 to 102 points; the higher the score, the stronger the PTSS (α=.93).

The questionnaire also included questions about the demographic characteristics of the participants.

The procedure was approved by the ethics committees of the sponsoring university and the organism which funded the study. Parents were required to provide their passive consent while the participants gave their active assent. Afterwards, psychology students applied the questionnaire in the adolescents’ schools. The participants were given a snack in way of thanks.The SB were evaluated in October 2009. The perceived magnitude of the February 2010 earthquake, the fear experienced during it, and the strength of the participants’ PTSS were evaluated in May 2010.

Descriptive analyses, including bivariate correlations, were run in SPSS (IBM Corporation, 2012).The hypothesized mediational path model was tested in MPlus (Muthén & Muthén,1998–2012), using bootstrap with 10,000 iterations to generate significance tests and confidence intervals for the estimated parameters (Hayes, 2013; MacKinnon, 2008). Age and gender were introduced as control variables.

Table 1 presents the descriptive statistics and the correlations for all variables. As compared to the range of possible scores, the average scores suggest that participants reported relatively high self-efficacy (23.96 points over a maximum of 30), perceived the earthquake to be of low magnitude (3.82 points over a maximum of 14), experienced moderate fear (3.67 points over a maximum of 6), and experienced low PTSS three months after the earthquake (28.45 points over a maximum of 102).

Contrary to our expectations, perceived magnitude was not associated with fear or PTSS. Consequently, our first hypothesis was not supported by the data. As was expected, self-efficacy beliefs were inversely associated with the fear experienced, and with PTSS, whereas fear was directly associated with PTSS.

The results for the proposed path analysis (Figure 1) are presented in Table 2. Both SB and fear predicted PTSS. Furthermore, the effect of SB over PTSS was mediated by fear (b=-.053, p=.047, 95% CI [-0.105,-0.001]); the stronger the SB, the milder the fear, the milder the fear, the weaker the PTSS).

Figure 1.

Path diagram of predictive relations.

(0.05MB).

In addition, results showed than age predicted PTSS (the older the participant, the stronger the PTSS) but, contrary to findings from previous studies, gender was not predictive of PTSS. Whereas females had greater fear (Mdiff=1.50,t=-6.22,p<.001, d=0.85), and greater PTSS (Mdiff=7.90; t=-4.06; p<.001, d=0.53) than males, we hypothesized that fear acted as a mediator in the relationship between gender and PTSS. The path analysis made it possible to evaluate this emerging hypothesis. The results of this analysis supported the mediational hypothesis (b=.15; p<.001), suggesting that gender differences in PTSS may be related to males’ and females’ initial emotional experience of the event.

The goal of the present study was to evaluate the association between self-efficacy beliefs previous to an earthquake, the earthquake's perceived magnitude, and the fear experienced during the disaster with PTSS. Results showed a low level of post-traumatic stress in adolescents who participated in this study. Furthermore, age, SB and fear predicted PTSS, with part of the effect of SB mediated by fear. The effect of gender on PTSS was totally mediated by fear. Finally, the perceived magnitude of the event was not predictive of fear or PTSS.

The low level of stress symptomatology 3 months after the earthquake is consistent with previous research. The APA (2000) reports that about 50% of people with PTSD are usually completely recovered within 3 months of the traumatic event. In addition, all participants lived in Santiago, a city that resisted the earthquake in a good way, which was not affected by the tsunami, and which quickly returned its normal functioning after the event. This is reflected by the fact that participants reported little material damage caused by the earthquake (perceived magnitude) and only 1.8% of participants reported physical damage from the earthquake.

Despite the low level of PTSS, several interesting findings were observed. First, the lack of an association between perceived magnitude and PTSS contradicts prior observations (Bokszczanin, 2008; Sumer et al., 2005). As mentioned before, the magnitude of the earthquake was evaluated through questions posed to adolescents from the same city about the damage caused by the earthquake. Future studies should look at more objective measures of the earthquake's magnitude (for example, by including participants from different cities) in order to determine its role more reliably.

The association between SB and PTSS, as well as the mediating role of fear, are consistent with earlier suggestions (Başoğlu et al., 2004; Benight & Harper, 2002; Benight et al., 1999; Bosmans et al., 2013; Sumer et al., 2005). Individuals with a better sense of self-efficacy feel less fear during adverse situations because they trust their ability to deal with them (Williams, 1995); also, such beliefs are likely to favor an emotional response that is more circumscribed to the event at hand, which may in turn result in a lower PTSS.

Fear also operates as a mediator in the relationship between gender and PTSS. This is a relevant finding, since the literature shows that women display greater PTSS levels than men, but reasons for it remain unclear (Tolin & Breslau, 2007). In line with this observation, females displayed greater PTSS levels than males when gender and PTSS were associated in the absence of other variables, but when the relation was examined taking fear into account, the direct effect of gender on PTSS disappeared, suggesting that the relationship between gender and PTSS is mediated by fear.

Finally, age was directly related to PTSS, but the reasons for this are not evident. This finding contradicts results observed in the past (Bokszczanin, 2007), and highlights the need for further research in the future.

Some limitations of the study should be noted (Hartley, 2012). First, we used a scale that measured general self-efficacy beliefs and not beliefs that are specific to cope with disasters. Bandura (2006b) suggests that people differ in the areas in which they cultivate their SB, so future research should specifically measure self-efficacy to cope with natural disasters, in order to have a more reliable estimate of their role in the development of PTSS. Second, because the original study was designed to assess normal adolescent development, no other antecedents of stressful response were available to incorporate in the study.

In spite of the previous limitations, the use of data collected prior to the natural disaster infuses our result with important insights which should inform studies of reactions to natural disasters and aid the development of PTSS prevention programs (Leiva-Bianchi et al., 2012). Specifically, our results highlight the role of SB in the affective experience (fear and PTSS) and the possibility of targeting them in preventive interventions. For example, interventions aimed at providing adolescents with information about what to do in the event of an emergency situation may increase adolescents¿ sense of personal efficacy to deal with the events, decreasing the fear experienced and the subsequent emotional consequences.

This study was supported by CONICYT through Fondecyt grant # 1120945, with Patricio Cumsille as principal investigator, and a doctoral fellowship granted to the first author.