Correlational Validity and Biomarker Associations of the Korean Computerized Cognitive Function Test (CFT-S) Relative to the Seoul Neuropsychological Screening Battery in MCI and Alzheimer's Disease.

INTRODUCTION: This study evaluates the clinical validity of the Korean Computerized Cognitive Function Test (CFT-S) by comparing its domain-specific scores with those of the Seoul Neuropsychological Screening Battery-II (SNSB-II) in patients with Mild Cognitive Impairment (MCI) or Alzheimer's Disease (AD). METHODS: A total of 300 participants (MCI: n = 163; AD: n = 137) from Severance Hospital completed both CFT-S and SNSB-II assessments within a two-week interval, along with brain MRI and APOE genotyping. Pearson correlations and multiple regression analyses examined relationships between cognitive scores and biomarker variables. Receiver operating characteristic curves assessed diagnostic accuracy. Bland-Altman plots evaluated agreement across five shared cognitive domains. RESULTS: CFT-S index scores showed significant positive correlations with SNSB-II in attention, language, visuospatial, and executive domains (r = 0.59-0.71, p < 0.001). The memory domain showed a lower correlation in AD patients (r = 0.28), reflecting limitations under severe impairment. Hippocampal volume was positively associated with MMSE (r = 0.54), CFT-S memory (r = 0.50), and SNSB memory scores (r = 0.52). Education correlated with MMSE (r = 0.32) but not with CFT-S or SNSB, suggesting minimal education bias. APOE-ε4 carriers had smaller hippocampal volumes, higher FBB-PET BAPL scores, and poorer cognitive outcomes. The Bland-Altman plots demonstrated acceptable agreement at the group level between CFT-S and SNSB-II across all cognitive domains, with small mean biases and symmetric distributions despite relatively wide limits of agreement. CONCLUSION: CFT-S index scores and Bland-Altman plot analysis demonstrated validity relative to SNSB-II, with significant associations to hippocampal atrophy and genetic risk factors. The findings support CFT-S as a viable and efficient cognitive assessment tool for diagnosing MCI and AD.