Unit-specific calibration of Actigraph accelerometers in a mechanical setup - Is it worth the effort? The effect on random output variation caused by technical inter-instrument variability in the laboratory and in the field

Abstract

Conclusion: The application of unit-specific calibration factors to data collected during free living conditions had no apparent effect on inter-instrument variability. In all probability, the effect of technical calibration was primarily attenuated in the field by other more dominant sources of variation. However, routine technical assessments are still very important for determining the acceleration responses in the batch of instruments being used and, if performed after every field use, for preventing decidedly broken instruments from being returned into the field repeatedly.