Digital questionnaire response time (DQRT): a ubiquitous and low-cost digital assay of cognitive status

Abstract

Digital survey tools have all but replaced paper and pen in the psychological sciences and consequently new forms of potentially useful research paradata are now routinely gathered. A particularly common byproduct of research are questionnaire timestamps, which some have suggested can be used as a measure of cognitive function. In this paper, we conducted a comprehensive validation of this measure, which we call the ‘digital questionnaire response time’ or ‘DQRT’. Using data from N=2979 users of a smartphone app, we examined how best to quantify DQRT, characterized its cognitive, clinical, and demographic correlates, established its psychometric properties, and highlighted substantial, but addressable, potential confounds inherent in the measure. We conclude that DQRT has important limitations, but on the whole can serve as a valid and reliable index of cognitive processing speed that can be gathered at unprecedented scale, unobtrusively, and repeatedly, during a variety of real-world digital behaviors.