A systematic review of passive data for remote monitoring in psychosis and schizophrenia

Abstract

There is increasing use of digital tools to monitor people with psychosis and schizophrenia remotely, but using this type of data is challenging. This systematic review aimed to summarise how studies processed and analysed data collected through digital devices. In total, 203 articles collecting passive data through smartphones or wearable devices, from participants with psychosis or schizophrenia were included in the review. Accelerometers were the most common device (n = 115 studies), followed by smartphones (n = 46). The most commonly derived features were sleep duration (n = 50) and time spent sedentary (n = 41). Thirty studies assessed data quality and another 69 applied data quantity thresholds. Mixed effects models were used in 21 studies and time-series and machine-learning methods were used in 18 studies. Reporting of methods to process and analyse data was inconsistent, highlighting a need to improve the standardisation of methods and reporting in this area of research.

Fig. 1. PRISMA flow diagram presenting the article screening process.

The flowchart shows the number of articles identified by the searches across the four databases and the number removed at the title and abstract screening and full text screening stages. Of the 9492 unique articles identified in the searches there were 203 included in the review. The template for the diagram was taken from the PRISMA 2020 guidelines.

Fig. 2. Sensors used by devices and features derived from sensor data for each type of device.

The circular bar plots show the types of sensors used by each device group, with the bar representing the percentage of devices in each group using that sensor. The horizontal bar plots show the number of studies that used each feature, coloured by behaviour type (phone use, sleep, location/mobility, physiology, physical activity, and circadian rhythm). Figure a shows results for the smartphone device group, b for accelerometers, c for smartwatches & commercial fitness bands and d for other wearables. Findings for the pedometer device group are not shown. TST total sleep time, EDA electrodermal activity, ECG electrocardiogram.