Preparing and validating character strength training package and its effectiveness on assertiveness skills of adolescents

Background: The present study was to prepare and validate character strength training package and effectiveness on assertiveness skills of adolescents. Materials and methods: This was a quasi-experimental study with a pretest-posttest design with a control group. First, the training package was prepared and validated. Once the goals were identified, appropriate content was prepared for each strength. Finally, after applying the opinion of experts, a training package was developed. Content validity index (CVI) and content validity ratio (CVR) were high for all objectives in the training protocol. Character Strength training package in the form of 12 sessions compiled 70 minutes. The statistical population included female high school students who were studying in schools in Tehran in the academic year 2020-2021. Students were selected by available sampling method and answered the assertiveness questionnaire. Among them, 30 students whose expression was a deviation below average were randomly assigned to the experimental group (n = 15) and the control group (n = 15). The Gambrill and Ritchie (1975) Expression Questionnaire was used to assess assertiveness. Results: The results of univariate analysis of covariance (ANCOVA) showed that the mean post-test scores in the experimental group were higher than the control group. Conclusion: Based our findings, it can be concluded that the prepared character strength training package had an effective role in increasing adolescents' assertiveness