The Capture24 project is a methodological research activity, part-funded by the ESRC and undertaken in collaboration with the Dr (Charlie) Foster’s British Heart Foundation Public Health group, previously located in Oxford, now transferred to Bristol). This involved participants wearing a small camera that recorded an image every 45 seconds and an accelerometer, and keeping a self-completion day diary, all on the same day. The diary and the camera record were independently coded using the detailed HETUS 4-digit activity classification. Though we found some errors in the respondents’ timing of starts and ends of particular events, the total durations of time devoted to each broad category of activity was nearly identical in the camera and diary records, indicating that the timing errors are random and uninformative. We also found that the camera and the diary records correlate well with the variation in motion recorded by the accelerometer. We arrive at a strong criterion variable-based justification of the PAPI time diary method (results in CAPTURE-24 Testing self-report time-use diaries against objective instruments in real time)
The general science journal Nature produced a nicely illustrated editorial on our work on this project (Pearson 2015) and also a video of the work. A description of the outcomes was published (together with several other pieces from CTUR members) in a special issue of BMC Public Health in 2019, and a major article reporting this work was published in Sociological Methodology in 2020. The next stage of this work, in collaboration with the University of Western Australia, uses similar methods (diaries, cameras, smart watches) to evaluate the health effects of active modes of travel (walking, cycling).