MECHANICAL MEASUREMENT OF THE MOTOR ACTIVITY OF INSTITUTIONALIZED MENTALLY RETARDED PERSONS (ASSESSMENT)
Mechanical measurements of motor activity are more precise, and may be less reactive, than judgments provided by human observers in the behavioral diagnosis and treatment of activity disorders frequently displayed by mentally retarded persons (e.g., hyperactivity, hypoactivity). The actometer (Schulman & Reisman, 1959) is a modified self-winding watch capable of objectively and reliably transducing the forcefulness of the wearer's body movements. Actometers were attached to four body sites (left and right wrists and ankles) of 18 institutionalized, profoundly mentally retarded men and women (ages 21 to 49). Measurements were taken twice daily during 30 minute intervals (mid-morning and mid-afternoon) under structured conditions, to provide a replicable context for the measurement of participants' activity levels. This study addressed questions of methodological importance in using the actometer with members of this subject population. Large amounts of day-to-day variability prompted use of a digital filtering procedure described by Tryon (1983) to reduce extraneous variability (noise), while preserving systematic variations (signals) in each participant's time series. A repeated measures analysis of variance was performed to investigate the variables of interest in this study (a.m. or p.m. time of day, upper or lower body torso, left or right side of the body, five-day blocks of recording trials, sex of participant). Time of day was the only significant main effect (morning activity levels were higher than afternoon values). Site of attachment of the actometer exerted a marked influence on the activity recordings obtained for individual subjects, in terms of the percentage distribution scores calculated for each body site and intercorrelations computed among scores. Results suggested that scores from left and right side of the same torso region overlapped to such an extent that little information would be lost by monitoring only two contralateral sites from different torso regions. Subjects differed appreciably in behavioral stability, as well as their characteristic activity dispositions. However, 20 days of recording was a sufficiently long interval to obtain stable estimates of each participant's mean level of activity.
PFADT, ALBERT GOTTFRIED, "MECHANICAL MEASUREMENT OF THE MOTOR ACTIVITY OF INSTITUTIONALIZED MENTALLY RETARDED PERSONS (ASSESSMENT)" (1984). ETD Collection for Fordham University. AAI8506353.