Development of a subjective cognitive decline questionnaire using item response theory: A pilot study

Abstract

Background Subjective cognitive decline (SCD) may indicate unhealthy cognitive changes, but no standardized SCD measurement exists. This pilot study aims to identify reliable SCD questions. Methods 112 cognitively normal (NC, 76±8 years, 63% female), 43 mild cognitive impairment (MCI; 77±7 years, 51% female), and 33 diagnostically ambiguous participants (79±9 years, 58% female) were recruited from a research registry and completed 57 self-report SCD questions. Psychometric methods were used for item-reduction. Results Factor analytic models assessed unidimensionality of the latent trait (SCD); 19 items were removed with extreme response distribution or trait-fit. Item response theory (IRT) provided information about question utility; 17 items with low information were dropped. Post-hoc simulation using computerized adaptive test (CAT) modeling selected the most commonly used items (n=9 of 21 items) that represented the latent trait well (r=0.94) and differentiated NC from MCI participants (F(1,146)=8.9, p=0.003). Conclusion Item response theory and computerized adaptive test modeling identified nine reliable SCD items. This pilot study is a first step toward refining SCD assessment in older adults. Replication of these findings and validation with Alzheimer’s disease biomarkers will be an important next step for the creation of a SCD screener.

Is function in instrumental activities of daily living a useful feature in predicting Alzheimer's disease dementia in subjective cognitive decline?

“…Third, the question “Do you have problems with your memory?” is considered a valid measure for global memory functioning . However, patients may assume all kinds of cognitive problems within that question.…”

“…is considered a valid measure for global memory functioning. 42 However, patients may assume all kinds of cognitive problems within that question. Also, assessing SCD using only a single memory question may limit the strength of the conclusions drawn regarding the utility of IADL above and beyond SCD.…”

Outcomes of stable and unstable patterns of subjective cognitive decline – results from the Leipzig Longitudinal Study of the Aged (LEILA75+)

“…First, SCD was only measured by asking a simple question concerning memory problems. Even though the question “Do you have problems with your memory?” may be a valid measure for global memory functioning [31], there is a lack of psychometric data concerning its longitudinal use. Future investigations of the stability of SCD with more comprehensive assessments (e.g., assessing other domains but memory or asking for related worries) could shed more light on the potential link to MCI and dementia progression risk.…”

A Conceptualization of the Utility of Subjective Cognitive Decline in Clinical Trials of Preclinical Alzheimer’s Disease

“…SCD severity can be measured in a variety of ways, for instance, according to how many SCD items an individual endorses, or alternatively, according to the magnitude of a total SCD score. An intriguing question is whether endorsing an increasing set of SCD items in a simple ‘dose-response’ type fashion may monotonically predictive of AD-dementia, and whether this could replace the less informative ‘total score’ method (Gifford et al 2015b; Rabin et al 2015). The rationale is that each item could be weighted according to AD-risk (Rabin et al 2015).…”