External Validation of the GERAADA Score: A Pooled Analysis of International Validation Studies

All articles of this category (opens in new window) Background: An essential step in assessing the performance of risk prediction models is the external validation outside the original derivation cohort. The recent introduction of the German Registry for Acute Aortic Dissection Type A (GERAADA) score has prompted several groups to evaluate its predictive accuracy in independent populations. Methods: We performed a systematic literature search to identify studies that validated the GERAADA score in institutional or national cohorts. Studies including patients from the original derivation cohort were excluded. Data on calibration [observed-to-expected (O/E) mortality ratio] and discrimination [area under the receiver operating characteristic curve (AUC)] were extracted and pooled employing a random-effects meta-analysis. Results: A total of 15 studies that validated the GERAADA score were published between 2021 and 2025. After exclusion of duplicate populations and centers in the derivation cohort, a total of 10 studies were analyzed. In total, 7,835 patients who underwent surgery between 2000 and 2023 constituted our meta-analysis population. The overall predicted 30-day mortality by the GERAADA score was 16.8%, compared to an overall observed mortality of 13.5%. The pooled O/E ratio suggested a trend toward overestimation of mortality by the score, although this was not statistically significant (O/E = 0.82, 95% CI: 0.63–1.07;). Discrimination was good across studies, with a pooled AUC of 0.77 (95% CI: 0.71–0.83;). Conclusion: External validation across multiple international cohorts suggests that the GERAADA score slightly overestimates 30-day mortality, though not significantly. The score demonstrates good discriminatory ability and remains the most robust predictive tool currently available for patients undergoing surgery for Acute Type A Aortic Dissection. Publication History Article published online: 17 February 2026 © 2026. Thieme. All rights reserved. Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany