Performance of study partner reports in a non-demented at-risk sample.

INTRODUCTION

The Clinical Dementia Rating (CDR) Scale is a gold standard for staging impairment in Alzheimer's disease and other dementias (ADRD). The Quick Dementia Rating System (QDRS) offers similar results in 3 to 5 minutes without a trained clinician. This study aimed to (1) investigate concordance between comparably derived QDRS and CDR global scores, (2) examine item-level QDRS/CDR agreement, and (3) compare sample characteristics and cognitive performance across QDRS/CDR global concordant/discordant groups.

METHODS

The study included 351 QDRS/CDR pairs from 297 participants in the Wisconsin Registry for Alzheimer's Prevention (WRAP). Analyses included descriptive indices of QDRS/CDR agreement, lasso logistic regression, tetrachoric correlations, and linear mixed models.

RESULTS

The QDRS global/CDR global concordance rate is 70.66%. Memory item discrepancies were primarily responsible for QDRS/CDR global rating discordance. Average cognitive scores were highest in concordant-normal QDRS/CDR and lowest in concordant-abnormal QDRS/CDR.

DISCUSSION

The QDRS effectively screened for impairment in this sample. Future analyses will investigate QDRS relations to ADRD biomarkers.

HIGHLIGHTS

The Quick Dementia Rating System (QDRS) effectively screened for impairment in Alzheimer's disease and other dementias (ADRD) in a non-demented sample. Concordance rate between QDRS global and Clinical Dementia Rating (CDR) Scale global scores is 70.66%. Memory item discrepancies primarily cause QDRS/CDR global score discordance. Cognitive scores are associated with QDRS/CDR concordances/discordances. Future analyses will explore QDRS relations to ADRD biomarkers.