Feasibility of ecological momentary assessment in measuring physical activity and sedentary behaviour in shift and non-shift workers.

Background: Previous studies assessing shift workers' behaviours have mainly used self-report recall questionnaires, however these measures don't always account for variations in work schedules. Alternative methods that allow for real-time assessments tailored to capture variations in work patterns might provide more accurate measures of physical activity (PA) and sedentary behaviour (SB). Therefore, the aim of this study was to evaluate the feasibility of Ecological Momentary Assessment (EMA), which provides real-time evaluations of PA and SB in shift workers. A secondary aim was to compare shift workers and non-shift worker responses.

Methods: Participants (n = 120; 58% female, mean M_age=36.0), included 69 shift workers and 51 non-shift workers. After downloading the EMA app, shift workers received either interval-contingent tailored (SW-T) or standardized EMA prompts (SW-S) over 7-10 days, while non-shift workers received standardized prompts (NSW-S) for seven days. Prompts were scheduled five times daily, every three hours. The EMA survey asked participants to report their current activity, including type, duration, and location of physical activity and sitting. Feasibility was assessed by analysing recruitment, retention, and compliance rates (EMA surveys completed) across SW-T, SW-S, and NSW-S groups.

Results: Approximately 78% of invited workers enrolled, and all enrolled workers completed at least one prompt on 4 out 7 days in the NSW-S and 7 out of 10 days in the SW group. Workers who chose not to participate reported unwillingness to travel for meetings (n = 14), while others did not respond (n = 20). Participants completed an average of 24 surveys per day, each one taking less than 30 s to complete. Overall, 64% of EMA surveys were started and completed. SW-S completed the least prompts (57%), while SW-T and NSW-S completed 64% and 68%, respectively (p = 0.90). On average, workers missed 36% EMA surveys which was similar for SW and NSW (p = 0.05).

Conclusion: Our study represents one of the few studies that has used EMA in the shift work population with adaptation to shift schedules. The findings showed a modest compliance to EMA. Strategies are needed to enhance compliance rates. However, EMA shows promise for capturing real-time behaviours in shift workers' natural work environments.