The breakdown of semantic memory appears early in Alzheimer's disease (AD). Lexico-semantic difficulties (e.g. difficulties in retrieving words and their meaning) are among the first symptoms of the disease. In order to screen this lexico-semantic decline, we propose the mini-SKQ, a semantic knowledge questionnaire. Mini-SKQ explores semantic impairment in AD patients with 12 questions. We administer mini-SKQ to 77 participants, 39 AD and 38 healthy old people. Results showed a significant difference between the groups: AD patients made significantly more errors than healthy old people. The Receiver operating characteristic (ROC) analysis established the optimal cut-off score of the mini-SKQ at 3 errors (sensitivity 61,5%, specificity 89,5%) in differentiating between AD patients and healthy old people. The mini-SKQ is a fast and easily administered questionnaire. Results indicated favorable indicators to screen semantic knowledge. These first observations underline that mini-SKQ could potentially be attractive for screening semantic memory deterioration.
Keywords: Alzheimer's disease; questionnaire; screening; semantic memory.