Measuring Cognitive Function and Cognitive Decline With Response Time Data in the National Social Life, Health, and Aging Project.

OBJECTIVES: Scholarly, clinical, and policy interest in cognitive function has grown over the last several decades in part due to large increases in Alzheimer's disease and related dementias as populations age. However, adequate measures of cognitive function have not been available in many research data sets. We argue that a wealth of previously unexploited survey data exists to model cognition and cognitive decline. METHODS: We use metadata of the time it takes older respondents in the National Social Life, Health, and Aging Survey, which we label response times (RTs), to answer questions in a standard cognitive assessment. We compare several measures of RT to a survey-adapted form of the Montreal Cognitive Assessment (MoCA). RESULTS: We show that RTs predict both concurrent and future MoCA scores. Our results show that longer and more varied RT at baseline predict lower MoCA scores 5 years later, net of baseline scores and controls. We also show that the effect of RT measures on predicting current MoCA differs for individuals of different races and ages, but are not different by gender. DISCUSSION: Our paper demonstrates that RTs constitute a separate powerful measure of cognitive functioning. RTs may be remarkably useful both to clinicians and social scientists because they can increase the accuracy of cognitive assessment without increasing the time it takes to administer the assessment.