A newly developed amnestic subjective cognitive decline questionnaire shows high internal consistency and inter‐rater reliability

Background Subjective cognitive decline (SCD) represents a state in which a participant perceives a decline in cognitive functions, yet standardized psychological tests remain within expected performance compared to age‐ and education‐matched controls. SCD is growingly recognized as a risk state for mild cognitive decline (MCI), and eventually, dementia. In this study, we introduce a newly developed Amnestic Subjective Cognitive Decline questionnaire (aSCDq), an instrument with four screening and five severity items (Table 1). We present preliminary internal consistency and inter‐rater reliability results. Method We analyzed the clinimetric data from 52 older adults (age 67.2 ±4.4 years), 9 diagnosed with amnestic Mild Cognitive Impairment (MCI), 16 with amnestic Subjective Cognitive Decline (aSCD), and 27 healthy older adults (HOA). We used polychoric correlation matrixes in a principal component analysis to assess the internal consistency of the four screening items, and to analyze the correlation between subject and informant response in all items. Result High internal consistency was found regarding the four screening items, resulting in a single component with an eigenvalue of 3.3, and 0.83 explained variance. High inter‐rater correlations in all screening items were found (1: 0.9, 2: 0.8, 3: 0.5, 4: 0.7), with more variable correlations demonstrated in severity items (s1: 0.3, s2: 0.5, s3: 0.7, s4: 0.9, s5: 0.6). Higher scores (i.e. worst memory complaints) were consistently reported by subjects in HOA and aSCD groups, and by informants in the MCI group. Conclusion Based on these preliminary results, the aSCDq has been shown to be a consistent and reliable tool to determine aSCD in older adults. The inter‐rater differences are slight but consistent with previous literature. For a full validation of this instrument, a higher number of participants will be necessary.