Martin Luther King Jr. Day
Our office will be closed Monday, Jan 18th in observance of Martin Luther King Jr. Day. We will reopen at regular business hours on Tuesday, Jan 19th.
Intermonitor Variability of GT3X Accelerometer
- Added on July 27, 2012
The main purpose of this study was to assess the inter-monitor reliability of the tri-axial GT3X Actigraph accelerometer over a range of physical activities (PA). This device collects motion data on each of the vertical (Y), horizontal right-left (X), and horizontal front-back (Z) axes and also calculates the vector summed value √X2+Y2+Z2 known as ‘vector magnitude’ (VM). 8 GT3X accelerometers were worn at the same time by the same participant. Accelerometers were placed back-to-front, all facing forward and in sets of 4 securely taped together, attached to a belt and allocating each block above either left or right hip at waist level. Inter-monitor reliability was assessed during 6 conditions: rest, walking (4 and 6 km·h-1), running (8 and 10 km·h-1) and repeated sit-to-stand (40 times·min-1). The intra-class correlation coefficients were high for X, Y and Z axes (i. e., all ≥0.925) and for VM (≥0.946). In conclusion, we found good inter-instrument reliability of the GT3X accelerometer across all planes, yet our results also suggest that the X and Z axes do not provide further benefits over the ‘traditional’ Y-axis to assess the movement in typical PA.
Link to Abstract: http://www.ncbi.nlm.nih.gov/pubmed/22791617