Validation of foot plantar pressure sensor data used to estimate standing, sitting, and moving durations in one working day

Abstract

BackgroundMaintaining immovable postures for long durations might be a cause of low back pain. However, the relation between low back pain and the maintenance of postures for long durations has been unclear. Therefore, the durations of several postures in one working day should be measured to evaluate the risk of low back pain, although the available measuring methods are limited. To the best of our knowledge, no study has reported the development and investigation of a foot plantar pressure sensor for measurement of standing, sitting, and moving durations in daily work routines. Thus, in this study, we aimed to develop a foot plantar pressure sensor that could withstand long-term loads in the workplace. Furthermore, we aimed to evaluate the estimated results of standing, sitting, and moving durations among factory workers using the developed foot plantar pressure sensor. MethodsThe developed foot plantar pressure sensor obtained a percentage difference within ±5% to estimate standing, sitting, and moving durations in the laboratory. We measured foot plantar pressures of 20 factory workers to estimate standing, sitting, and moving activity in one working day using data obtained by the foot plantar pressure sensor. The estimated standing, sitting, and moving durations were compared with the human estimation of photo data obtained by a wearable camera. ResultsThe agreement rate (Cohen's kappa coefficient) was 0.75 between the evaluation using the foot plantar pressure sensor data and human estimation using a wearable camera. Cohen's kappa coefficient was 0.81 in subjects who sat for ≥30% during daily work and 0.68 in subjects who sat for <30%. ConclusionOur foot plantar pressure sensor effectively measured the standing, sitting, and moving durations in daily work that requires various movements and assumption of postures.