Review on unobtrusive estimation of team processes underlying team situation awareness: shared mental models and team coordination

Team situation awareness (SA) is essential for effective team performance. Yet, current methods rely on potentially biased self-reports and obtrusive tools such as task probes. Objective, unobtrusive, and continuous methods for monitoring team SA could support its improvement. In contrast to individual SA, unobtrusive measures of team SA have not been systematically reviewed. Because team SA is an umbrella concept, we adapted a framework proposed by Salmon et al., identifying two components that can potentially be measured unobtrusively: shared mental models (SMMs) and team coordination. This systematic review examines behavioural and physiological technologies that may enable unobtrusive measurement of these components.

We conducted a systematic literature review of studies investigating behavioural technologies, such as verbal communication and eye-tracking, and physiological technologies, such as electroencephalography, for unobtrusive measurement of team SMMs and coordination. We searched Web of Science (May and July 2025) for relevant literature published between 2000 and 2025. We included peer-reviewed articles published in English. In total, 19 studies addressing team SMMs and 33 addressing team coordination were included. We extracted sample and team size, task environment, operationalisation of team SMMs and coordination, and their relationship with unobtrusive measures.

Cardiac measures (42%) and verbal communication (47%) were most popular for estimating team SMMs, while functional near-infrared spectroscopy (27%) and cardiac measures (30%) were most popular for estimating team coordination. Interpersonal synchrony-the temporal contiguity and interdependence of physiological and/or behavioural activity between teammates-was applied in 70% of team coordination studies. Studies covered diverse tasks and settings, from laboratory-based cognitive tasks and controlled physical tasks to real-world environments, including surgery. Various methods were used to operationalise SMMs and coordination, including participant experience, expert assessment, and self-reports.

Findings suggest that team SMMs and coordination cannot be measured as single, unified constructs using one unobtrusive measure. Instead, different measures may provide information about specific aspects of these processes. Future research should begin with task analysis to identify relevant aspects of team SA and derive appropriate measures for the specific task environment. Task-related behavioural actions also represent a potentially valuable, yet often overlooked, category of unobtrusive measures. A key limitation is the substantial variation in how SMMs and coordination were operationalised and measured, making direct comparisons difficult. Future work should investigate how identified measures relate directly to team SA using validated measures.