Am. Ekes et al., RELIABILITY OF LIFT ALERT((TM)) AS A FEEDBACK DEVICE FOR DETECTING CHANGES IN BODY POSITION, Journal of occupational rehabilitation, 5(1), 1995, pp. 17-25
The Lift Alert(TM) is, small battery-operated unit, usually worn on th
e back of a worker's collar that is designed to provide a form of biof
eedback about changes in trunk position during lifting tasks. The purp
ose of this study was to determine how consistent the Lift Alert(TM) w
as at each of five different sensitivity settings (A-E) in detecting c
hanges in trunk flexion in a given individual during a controlled bend
ing maneuver. The subjects were videotaped while performing a series o
f trials of bending maneuvers at each of the sensitivity settings acco
rding to a specific protocol. The videotapes were then converted onto
a computer program where the still images were captured and marked for
data analysis. The reliability of the Lift Alert(TM) was determined b
y calculating a coefficient of agreement, that is, the percentage of t
rials that were within both 10 and 15 degrees for each of the trials a
t a given setting for a single individual. The coefficient of agreemen
t for all trials at all five settings was 0.76 within 10 degrees and 0
.92 within 15 degrees. The results of this study suggest that the Lift
Alert(TM) is a reliable device for detecting changes in trunk flexion
during a controlled bending maneuver for a given individual.