en <span style=font-size:12pt><span style=line-height:normal><span style=font-family:Times New Roman,serif><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Aims:</span></span></span></b> <span style=font-size:10.0pt><span style=font-family:Cambria,serif>The rate of seat belt use among adolescents as a passenger age group is lower than that of adults. There is limited research on seat belt usage among adolescents. The present study aimed to compare the predictability of seat belt-wearing behavior among adolescents using the theory of planned behavior and its extension.</span></span></span></span></span><br> <span style=font-size:12pt><span style=line-height:normal><span style=font-family:Times New Roman,serif><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Instrument & Methods:</span></span></span></b> <span style=font-size:10.0pt><span style=font-family:Cambria,serif>This cross-sectional study was conducted among 952 adolescent students as car occupants. A researcher-developed questionnaire was used for data collection. In the extended theory of planned behavior, constructs related to threat appraisal were added to the theory of planned behavior. These constructs included perceived severity, perceived rewards, and perceived sensitivity. Structural equation modeling was used to determine which theory better predicts seat belt use behavior.</span></span></span></span></span><br> <span style=font-size:12pt><span style=line-height:normal><span style=font-family:Times New Roman,serif><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Findings:</span></span></span></b><span style=font-size:10.0pt><span style=font-family:Cambria,serif> The mean score for seat belt use among adolescent students was unfavorable. Structural equation modeling confirmed the validity of both the theory of planned behavior and its extension in predicting seat belt use behavior among adolescents. However, in the extended theory of planned behavior, the additional constructs of threat assessment—such as perceived rewards, perceived severity, and perceived sensitivity—showed no statistically significant relationship with behavioral intention. Consequently, the inclusion of threat assessment dimensions did not enhance the prediction of seat belt-wearing behavior.</span></span></span></span></span><br> <span style=font-size:12pt><span style=line-height:normal><span style=font-family:Times New Roman,serif><b><span style=font-size:10.0pt><span style=font-family:Cambria,serif><span style=color:#4f81bd>Conclusion:</span></span></span></b><span style=font-size:10.0pt><span style=font-family:Cambria,serif> The rate of seat belt use among adolescent students is unfavorable, and the theory of planned behavior is an appropriate framework for predicting seat belt use among this demographic. </span></span></span></span></span><br> Behavior,Seat Belt,Students,Adolescence,Theory of Planned Behavior, 315 321 http://hehp.modares.ac.ir/browse.php?a_code=A-10-88998-1&slc_lang=en&sid=4 F. Malekpour 1003194753284600369240 1003194753284600369240 No Department of Public Health, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran L. Tapak 1003194753284600369241 1003194753284600369241 No “Department of Biostatistics, School of Public Health” and “Noncommunicable Diseases Research Center”, Hamadan University of Medical Science, Hamadan, Iran B. Moeini 1003194753284600369242 1003194753284600369242 No “Department of Public Health, School of Public Health” and “Social Determinants of Health Research Center”, Hamadan University of Medical Sciences, Hamadan, Iran H. Sadeghi-Bazargani 1003194753284600369243 1003194753284600369243 No Road Traffic Injury Research Center, Tabriz University of Medical Sciences, Tabriz, Iran F. Rezapur-Shahkolai 1003194753284600369244 1003194753284600369244 Yes “Department of Public Health, School of Public Health” and “Research Center for Health Sciences” Hamadan University of Medical Sciences, Hamadan, Iran