A smartphone-based test for the assessment of attention deficits in delirium: A case-control diagnostic test accuracy study in older hospitalised patients

Abstract

Background Delirium is a common and serious acute neuropsychiatric syndrome which is often missed in routine clinical care. Inattention is the core cognitive feature. Diagnostic test accuracy (including cut-points) of a smartphone Delirium App (DelApp) for assessing attention deficits was assessed in older hospital inpatients. Methods This was a case-control study of hospitalised patients aged �65 years with delirium (with or without pre-existing cognitive impairment), who were compared to patients with dementia without delirium, and patients without cognitive impairment. Reference standard delirium assessment, which included a neuropsychological test battery, was based on Diagnostic and Statistical Manual of Mental Disorders-5 criteria. A separate blinded assessor administered the DelApp arousal assessment (score 0-4) and attention task (0-6) yielding an overall score of 0 to 10 (lower scores indicate poorer performance). Analyses included receiver operating characteristic curves and sensitivity and specificity. Optimal cut-points for delirium detection were determined using Youden's index.

Delirium

“…The DelApp is a computerized, objective test of arousal and attention that is implemented on a smartphone and is for use in both the general population and ICU patients. Case-control studies show a high sensitivity and a moderate-to-high specificity of DelApp in the detection of delirium 235,236 .…”

Pilot testing of a new electronic diagnostic support tool (AiD-DST) designed to identify the cause(s) of delirium

“…26 More-over, smartphone-based tests have been successfully validated in screening for delirium and discriminating it from dementia. 27 One of the challenges for an algorithm for delirium aetiology was the inter-patient variability in causality, creating a potential tension between inclusivity and ergonomics. Our original study identified key points of difference in patient presentation that would help focus clinical enquiry while avoiding redundancy in questions.…”

Comparing performance on the Months of the Year Backwards test in hospitalised patients with delirium, dementia, and no cognitive impairment: an exploratory study

“…As such these analyses are exploratory and should be considered hypothesis-generating rather than confirming. Data were derived from a case–control study of a software application for detecting attention deficits in delirium, and the recruitment and assessment methods are described in detail in the original study [ 20 ]. Briefly, patients were recruited from geriatrics and orthopaedics wards of the Royal Infirmary of Edinburgh and Glasgow Royal Infirmary, Scotland.…”

“…The reference standard assessment for delirium based on DSM-5 criteria was informed by the Delirium Rating Scale-Revised 98 [DRS-R98 [22]]. As part of the assessment several scales and cognitive tests were administered: The Observational Scale of Level of Arousal [OSLA, [23]], the Richmond Agitation-Sedation Scale [RASS [24]], the Short Orientation, Memory and Concentration Test [OMCT [25]] and the Abbreviated Mental Test [AMT10 [26]], MOTYB, Days of the Week Backwards, Counting Backwards from 20 to 1, and Digit Span [20].…”