Objective: To evaluate the efficacy of the cognitive-behavioral intervention provided to children by volunteer professionals in a tsunami-hit area in Thailand. The intervention was aimed to prevent the severe development of post traumatic stress symptoms, and to help the children who might recover spontaneously to do so more quickly.

Material and Method: One hundred and sixty children in Ranong province voluntarily participated in 2-days group activities on the 57^th day after the tsunami. The manualized intervention had been designed based on cognitive-behavioral model. Three domains of post traumatic stress reactions were targeted, intrusion, arousal, and avoidance. The Children’s Impact of Events Scale (13) (CRIES-13) was completed by the participants before and 2 weeks after the intervention.

Results: The program was generally well understood by the children. No difference in CRIES scores was observed before and after the children entered the intervention program. However, when the sample was categorized into two groups, the group that was more likely to develop PTSD showed a significant reduction in the scores, whereas a significant increase in the scores was evident in the other group.

Conclusion: The findings supported the efficacy of cognitive-behavioral intervention in the children who were prone to develop PTSD. The program needed to be adapted to suit the religious, socio-economic, and cultural background of the sample. The unchanged Avoidance scores in the present study were possibly explained by the general feeling that a tsunami might happen again and the parental involvement. The increase of post-intervention scores in otherwise normal sample, though not exceeding the cut-off, raised some concern, and possibly the need for screening before the intervention.

Keywords: Cognitive-behavioral therapy, Traumatic stress, Tsunami victims