Clinical trial NCT02590796: Validating Studies to Assess the Diagnostic Accuracy of a Software Application for Detection and Monitoring of Attentional Deficits in Delirium
Official title: MICA: Development of a Software Application for Detection and Monitoring of Attentional Deficits in Delirium
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Delirium
Dementia
Keywords: Delirium
Inattention
Medical device
Software application
Validation study
Diagnosis
Dementia
Lead sponsor: University of Edinburgh
Sponsor class: OTHER
Collaborators: name: Medical Research Council
name: NHS Lothian
name: University of Glasgow
name: NHS Greater Glasgow and Clyde
name: Cambridge Cognition Ltd
First posted: 2015-10-29
Enrollment: 907
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: OTHER
Time perspective: OTHER
Sampling method: PROBABILITY_SAMPLE
Study population: Royal Infirmary of Edinburgh (RIE) and Glasgow Royal Infirmary (GRI) general wards and intensive care units.

Scottish Dementia Research Network Register and Psychology, Philosophy and Language Science (PPLS) volunteer database.

Brief summary: The study has two phases: Phase B and Phase C. The purpose of the Phase B study is to determine the performance (sensitivity and specificity) of a smartphone application (DelApp) to identify delirium in the whole inpatient sample. The study also aims to determine the performance (sensitivity and specificity) of the DelApp to discriminate between delirium (with or without dementia) and dementia (without delirium).

The purpose of the Phase C study is to determine the efficacy of the DelApp software application in detecting delirium in unselected patients in an inpatient sample and to determine the performance of the DelApp to discriminate between delirium and dementia. The study also aims to explore the performance of the DelApp in tracking change in cognitive function.

Detailed description: The investigators previously developed a new neuropsychological test for the objective measurement of inattention in delirium, which was implemented on a purpose-built computerised device (Delbox). A prototype software application (DelApp) for smartphones has now been developed based on the same test.

The DelApp has many advantages over existing tests, including objectivity, automated scoring and ease-of-use. Studies in 30 hospital patients showed highly comparable performance between the Delbox and DelApp. Further proof-of-principle single-rater studies using the DelApp in more than 200 hospital patients have provided additional evidence of good performance of the DelApp.

Though there are strong positive findings from investigator pilot studies, larger-scale formal studies with blinded raters and more representative patient samples are now required.

The proposed study is part of a larger programme of work funded by the Medical Research Council (grant value £1.01M) on the optimisation and clinical validation of the DelApp, which consists of three stages: Phase A - optimisation of the DelApp and feasibility testing (REC no 15/SC00/19); Phase B - case-control studies in selected patients; and Phase C - validation studies in unselected patients. Ultimately investigators aim to generate a software product which will be fully licensed and commercially available to healthcare organisations.

The proposed Phase B studies will be carried out in hospitalised patients in general and acute medical wards and ICU. The objectives of these studies are (a) to assess diagnostic performance of the DelApp in discrete patient groups and to inform optimal cut-points (Phase B); and (b) to evaluate the diagnostic performance of the DelApp in unselected patients (Phase C). The studies will also contribute to a better understanding of the nature of neuropsychological deficits underlying delirium. At the end of these studies, the DelApp may be modified depending on the study results. Investigators will select the stimuli and subtests that provide the best balance of sensitivity and specificity.

Two case-control studies will be conducted involving patients recruited from general and acute wards (Study B.1) and ICU (Study B.2). Each study will run in two sites, i.e. the Royal Infirmary of Edinburgh (RIE) and the Glasgow Royal Infirmary (GRI). The performance of the DelApp (index test) against reference standard diagnosis will be independently assessed by two trained raters, with one pair of raters on each site. As in our prior case-control studies, convenience samples will be used, where clinicians are asked to identify patients in the target groups.

Hospitalised patients will be asked to undertake a number of tests at their bedside. These tests will be administered to patients once only. Patients will be visited by two different researchers on the same day, with a gap of approximately 15-60 min between assessment visits assuming that consent is provided in the first visit. The first visit will involve assessment of capacity and (in those thought likely to be capable of giving consent) obtaining informed consent, as well as assessment of delirium (reference tests) and cognition. The second visit will involve the DelApp assessment (index test). Thus, the index test and reference tests are administered by independent raters. Where the patient is unable to provide consent for themselves, proxy consent will be sought, and if granted, the same visits as above will occur.

The Phase C formal validation studies have a similar design to the case-control studies. The main difference is that unselected samples of patients will be recruited from general and acute medical wards (Study C.1) and ICU (Study C.2) in the GRI and RIE.

A subset of patients in studies C.1 and C.2 (N=60 combined) will undergo up to 4 repeat assessments (at least one day apart), along with the reference standard, to explore the performance of the DelApp in tracking change in cognitive function.

In the longitudinal assessments, researchers will ask patients able to provide consent at the time of recruitment if they consent to subsequent assessments even if at the time of these subsequent assessments the patient lacks capacity. However, during the subsequent assessments, it will be carefully checked if the patient assents to continue their participation in the study. In patients who initially lack capacity and have been included through consent from a legal proxy, and who are undergoing serial assessments, researchers will seek informed consent from patients at the beginning of each new testing session. If the patient regains capacity after the final assessment, the investigators will seek retrospective consent from the patient where possible.

Eligibility criteria: Inclusion Criteria:

* General Wards

  * Aged 65 or over
  * Capacity to provide written, informed consent or the availability of a suitable relative or welfare guardian/attorney who is able to provide informed consent on behalf of the participant.

ICU

* Aged 18 or over
* Capacity to provide written, informed consent or the availability of a suitable relative or welfare guardian/attorney who is able to provide informed consent on behalf of the patient.

Exclusion Criteria:

* General Wards

  * Unable to understand spoken task instructions
  * Vision or hearing impairment severe enough to preclude testing or interview
  * Photosensitive epilepsy

ICU

* Unable to understand spoken task instructions
* Pre-existing, known cognitive impairment including dementia
* Vision or hearing impairment severe enough to preclude testing or interview
* Photosensitive epilepsy
* A score on the Richmond Agitation-Sedation Scale of below -3

Primary outcomes:
measure: Diagnostic accuracy of the DelApp for diagnosing delirium
timeFrame: Baseline
measure: Diagnostic accuracy of the DelApp to discriminate between delirium (with or without dementia) and dementia (without delirium).
timeFrame: Baseline
Secondary outcomes:
measure: Accuracy of DelApp in measuring delirium severity
timeFrame: Baseline
measure: Length of stay
timeFrame: up to 3 months
measure: Mortality
timeFrame: 3 months
measure: Discharge location
timeFrame: up to 3 months
measure: Accuracy of DelApp to measure within-subject change in attentional functioning and delirium status over time
timeFrame: 2 weeks
measure: Inter-rater agreement of the DelApp
timeFrame: Baseline
Other outcomes:
Locations:
city: Edinburgh
country: United Kingdom
facility: University of Edinburgh
city: Glasgow
country: United Kingdom
facility: University of Glasgow
Study officials:
affiliation: University of Glasgow
name: David J Stott
role: PRINCIPAL_INVESTIGATOR
affiliation: Royal Infirmary of Edinburgh
name: Elizabeth Wilson
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Edinburgh
name: Timothy Walsh
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Glasgow
name: Tara Quasim
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Glasgow
name: Jonathan Evans
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Edinburgh
name: Christopher Weir
role: PRINCIPAL_INVESTIGATOR
affiliation: Medical Devices Unit
name: Alexander Weir
role: PRINCIPAL_INVESTIGATOR
affiliation: Medical Devices Unit
name: Stuart Parks
role: PRINCIPAL_INVESTIGATOR
affiliation: Cambridge Cognition Ltd
name: Jennifer Barnett
role: PRINCIPAL_INVESTIGATOR
References:
citation: Rutter LM, Nouzova E, Stott DJ, Weir CJ, Assi V, Barnett JH, Clarke C, Duncan N, Evans J, Green S, Hendry K, McGinlay M, McKeever J, Middleton DG, Parks S, Shaw R, Tang E, Walsh T, Weir AJ, Wilson E, Quasim T, MacLullich AMJ, Tieges Z. Diagnostic test accuracy of a novel smartphone application for the assessment of attention deficits in delirium in older hospitalised patients: a prospective cohort study protocol. BMC Geriatr. 2018 Sep 17;18(1):217. doi: 10.1186/s12877-018-0901-5.