METHODOLOGICAL CONSIDERATIONS IN THE QUANTITATIVE ASSESSMENT OF HUMAN PSYCHOMOTOR ACTIVITY
The literature concerning the measurement of human psychomotor activity was reviewed and was found to be inconsistent with respect to fundamental questions such as site of measurement, laterality and length of time over which movement should be measured.^ Forty right handed male volunteers, 20 adults and 20 children, wore modified wrist watches, actometers. All actometers had been calibrated and standardized to a known physical constant, G, a unit of force. Every subject wore an actometer on each arm and leg. Measurements for 10 days in which no abnormal movements were reported were entered into the data analysis. The data was analyzed for both actometer units per minute and for G force equivalents.^ A repeated measures analysis of variance (ANOVA) in which both days of the experiment and site of measurement were the repeated measures, was performed to determine mean level differences. Statistically significant differences were found over the 10 days of the study with subjects moving a great deal on days 3 and 5 and with low levels of movement on days 6 and 7. There was also a significant group by locus interaction with the adults exhibiting higher amounts of leg movement than children. No other factors attained statistical significance.^ Cumulative means for all loci of all subjects were analyzed. The only locus to stabilize over the 10 days of the study was the right wrist and this only within (+OR-)10% of the overall mean. Using a criterion of four loci stabilizing within (+OR-)10% of the day mean, only 77.5% of the subjects are stable. Using a criterion of three loci 95% of the subjects stabilize.^ Patterning differences between groups were investigated using covariance matrices. No differences between the patterns of movement of adults and children were found using Box's statistic. It was found that in order to describe a minimum of 60% of the variance of movement it would be necessary to measure four loci.^ Laterality was found to be a relatively unimportant consideration in the study of movement, either from a mean level differences perspective or from a patterning differences perspective. Age related differences were found to be important for studies concerned with mean level differences. The question of what site to measure was found to be subordinate to the question of the number of sites measured. All sites add information. In order to be reasonably certain that subjects have stabilized and that the complete pattern of movement has been described it would be necessary to measure four sites for a minimum of 10 days. ^
MCCARTHY, RICHARD HERBERT, "METHODOLOGICAL CONSIDERATIONS IN THE QUANTITATIVE ASSESSMENT OF HUMAN PSYCHOMOTOR ACTIVITY" (1981). ETD Collection for Fordham University. AAI8123558.