Supplementary Material for: Adaption and validation of the Greek version of Addenbrooke's Cognitive Examination III scale as a screening tool for perioperative cognitive impairment detection

Introduction: Postoperative cognitive dysfunction constitutes an extremely prevalent implication in individuals subjected to cardiac or non-cardiac surgery. This study aims to assess the validity and reliability of a culturally adapted Greek version of the Addenbrooke’s Cognitive Examination III (ACE-III) scale as a screening tool for perioperative neurocognitive status determination in elderly surgical patients. Methods: A cross-cultural adaptation and validation of instruments throughout the a cross-sectional study was conducted. The study sample consisted of 128 individuals over 55 years old scheduled for surgical intervention. All participants were screened twice; at the preadmission clinic and the day before surgery using the already established MoCA scale and the culturally adapted Greek version of the ACE-III scale. Subjects with a MoCA score of < 26 constituted the cognitively impaired group. Results: Regarding construct validity, ACE-III’s performance in detecting cognitive impairment was excellent (AUC =0.942; 95%CI 0.899-0.971). Convergent validity between ACE-III and MoCA scales was excellent (r= 0.876; 95%CI 0.839-0.905). Known group validity was confirmed since advanced age and lower educational attainment adversely impacted ACE-III’s total score (p<0.001). Additionally, specialists suggested face validity (mean 8.7 out of 10, SD 1.1). In terms of reliability, ACE-III demonstrated good internal consistency (Cronbach's alpha 0.786) and high inter-rater (ICC=0.936 [95%CI 0.921-0.941]) and test-retest reliability (ICC=0.972 (95%CI 0.958-0.981). Conclusion: The Greek version of ACE-III is a valid, and reliable screening tool that could be routinely employed perioperatively as a valid alternative to the MoCA test to distinguish the mild cognitively impaired from healthy elderly candidates for surgical interventions.