Postural stability: a proposed data analysis method

Balance platform data has been collected from sixty children and adolescents to compare the postural control strategies used by the normal and cerebral palsied populations. Of major interest is the strategy used to control posture by two groups. The authors suggest a methodology which conditions the raw data and uses several time and frequency domain matrices to identify whether the control strategy is constant throughout the test or varies while the test is in progress. If a single mechanism is used, then it can be assumed that the duration of the test is sufficient to warrant statistical comparisons between the populations. The results show that a 30-s test duration provides an epoch short enough to ensure signal stationarity yet long enough to also ensure a consistent control mechanism.<>