Evaluation of Traumatic Brain Injury Severity Using the Abbreviated Injury Scale and the Injury Severity Score: A Retrospective Study in Two Eastern European Centers.

: Traumatic brain injury (TBI) is a significant global public health issue, with long-term impacts on patients. This study examines the relationship between TBI severity, as measured by the Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS) at admission, and various sociodemographic, clinical, and injury-related factors. : We conducted a retrospective analysis using data from 164 adult TBI patients. All were admitted between March 2020 and June 2023 to two Eastern European tertiary hospitals. Variables included sex, age, education, employment, marital status, injury type and cause, place of injury, and clinical measures such as the Marshall score, AIS, and ISS. Statistical methods included Pearson's Chi-squared, Fisher's exact, Spearman correlation, Wilcoxon, and Kruskal-Wallis tests. : Most patients were male (65.9%), retired (59.8%), and urban residents (73.8%), with a mean age of 64.98 years. The most frequent mechanism of injury was falls (76.2%), typically occurring at home (61%). The predominant injury type was closed head trauma (93.3%). Most patients had mild AIS scores (75%), and the mean ISS was 6.52 (SD: 4.55). Statistically significant group differences were found for AIS among categories of Modified Marshall Score, injury type, and education categories and for ISS among categories of the Modified Marshall Score, injury type, cause and place of injury, employment status, and sex. No significant correlations were found between AIS or ISS and age or hospital length of stay. : AIS is more anatomically focused. ISS reflects broader systemic injury patterns and is more influenced by contextual factors. These findings are particularly relevant for the Eastern European population and can help develop better healthcare policies for the region.