AbstractBackgroundThe Everyday Cognition scale (ECog) is an informant‐rated questionnaire of cognitive and functional abilities. In recent years, it has been shown to be sensitive for the differentiation of older adults with mild cognitive impairment (MCI) (Farias et al, 2008; Russo et al, 2014), and to the diagnosis of neurodegenerative disease such as Alzheimer’s disease (Farias et al, 2020). However, little is known about its possible utility to predict MCI‐dementia progression in Alzheimer’s clinical syndrome (ACS).Method130 participants (63.8% females), with an average age of 75.27 (SD=5.91), and diagnosed with MCI, were assessed with a comprehensive battery of neuropsychological tests and functional scales, including ECog. In the 2 years follow‐up assessment, 20 participants were diagnosed with ACS. Binary logistic regression and ROC curve statistical analyses were performed.ResultSignificant correlations (p<.05) were found between ECog and neuropsychological tests such as Addenbrooke's Cognitive Examination‐Revised (ACE‐R), Mini‐Mental State Examination (MMSE), a Spanish version of the California Verbal Learning Test (CVLT), the Rey–Osterrieth complex figure test (ROCF) recall, the semantic verbal fluency and the Zoo map. Binary logistic regression results showed that ECog significantly explained the conversion to AD (p<.05). Baseline scores for ECog were significantly higher in participants who developed ACS after two years (p<.05). ROC curve showed a sensitivity of 80% and a specificity of 51% on the optimal cut‐off point (48.5) (AUC=0.69).ConclusionFunctional ability is highly related to cognitive domains. The ECog scale is an useful instrument for the early detection of MCI patients with high risk to develop ACS.