RESUMEN
BACKGROUND: Thoracic injury rule out criteria (TIRC) were first introduced as a decision instrument for selective chest radiography in blunt thoracic trauma in 2014. However, the validity of this model has not been assessed in other studies. In this regard, the present survey evaluates the validity of TIRC model in a multi-center setting. METHODS: In this cross-sectional study, clinical presentations and chest radiograms of multiple trauma patients referring to 6 educational hospitals in Iran were evaluated. Data were gathered prospectively during 2015. In each center, data collection and interpretation of radiograms were conducted by two different emergency medicine specialists. Measures were then taken for assessment of discriminatory power and calibration of the model. RESULTS: Data from 2905 patients were gathered (73.17% were male; the mean age was 33.53 ± 15.42 years). Area under the receiver operating characteristics curve of the TIRC model for detection of thoracic traumatic injuries was 0.93 (95%CI: 0.93-0.94). Sensitivity and specificity of the model were 100 (98.91-100) and 67.65 (65.76-69.45), respectively. The intercept of TIRC calibration plot was 0.08 (95%CI: 0.07-0.09), and its slope was 1.19 (95%CI: 1.15-1.24), which are indicative of the model being perfect in detecting presence or absence of lesions in chest radiograms. CONCLUSION: The findings are corroborative of external validation, good discrimination, and proper calibration of TIRC model in screening of multiple trauma patients for obtaining chest radiograms.