Validity of online versus in‐clinic self‐reported Everyday Cognition Scale (ECog): Online measures performed as well as repeating the in‐clinic assessment

Abstract

AbstractBackgroundClinical assessment of cognition and functional abilities plays an important role in identifying individuals at risk for cognitive decline, mild cognitive impairment (MCI), and dementia due to Alzheimer’s (AD). In‐person clinical assessments can be logistically challenging and deter broad participation in clinical studies, reducing diversity in AD research. Online assessments are an appealing alternative, but the validity of online compared to clinical in‐person assessments has not been established. Our goal was to determine whether the Everyday Cognition (ECog) Scale, which assesses decline in instrumental activities of daily living, collected online corresponds well with ECog collected in‐clinic. The correspondence of in‐clinic and online measures could not logically exceed the test‐retest reliability of the in‐clinic measure, so we used this as a benchmark for validity of the online measure.MethodSelf‐reported ECog was collected both in‐clinic and online from 94 older adults (characteristics described in Table 1) enrolled in both the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and Brain Health Registry (BHR). Associations between in‐clinic and online ECog scores were estimated using linear regression. Prediction error was corrected for optimism with 10‐fold cross‐validation. We estimated test‐retest reliability of in‐clinic ECog in 259 cognitively normal ADNI2 participants (characteristics described in Table 2) with two in‐clinic ECog measures, completed six months apart. Reliability was estimated using the intraclass correlation coefficient (ICC) and linear regression. Age, gender, education, and time between assessments were included as covariates in all regression models.Result (1) Validity of online ECog. Mean online ECog scores were significantly associated with mean in‐clinic ECog scores (β=0.81, 95% CI 0.64‐0.98, p=0.00). The optimism‐corrected R2 was 0.61 (95% CI 0.40‐0.82). (2) Reliability of In‐clinic ECog: The ICC was estimated to be 0.67 (95% CI 0.54‐0.79). Mean in‐clinic ECog scores collected at 6 months were significantly associated with in‐clinic ECog score collected at baseline (β=0.71, 95% CI 0.63‐0.78, p=0.00). The optimism‐corrected R2 was 0.61 (95% CI 0.51‐0.72).ConclusionThe online ECog corresponded well with in‐clinic ECog and provided as much information as repeating the in‐clinic ECog. This supports the validity of online ECog, a measure of functional and cognitive decline.