by M. Rhonda Folio+ Rebecca R. Fewell
Reliability and validity have been determined empirically. The normative sample consisted of 2,003 persons residing in 46 states. The PDMS-2 can be used by occupational therapists, physical therapists, diagnosticians, early intervention specialists, adapted physical education teachers, psychologists, and others who are interested in examining the motor abilities of young children.
- Reflexes: This 8-item subtest measures a child's ability to automatically react to environmental events. Because reflexes typically become integrated by the time a child is 12 months old, this subtest is only given to children birth through 11 months.
- Stationary: This 30-item subtest measures a child's ability to sustain control of his or her body within its center of gravity and retain equilibrium.
- Locomotion: This 89-item subtest measures a child's ability to move from one place to another. The actions measured include crawling, walking, running, hopping, and jumping forward.
- Object Manipulation: This 24-item subtest measures a child's ability to manipulate balls. Examples of the actions measured include catching, throwing, and kicking. Because these skills are not apparent until a child has reached the age of 11 months, this subtest is only given to children ages 12 months and older.
- Grasping: This 26-item subtest measures a child's ability to use his or her hands. It begins with the ability to hold an object with one hand and progresses up to actions involving the controlled use of the fingers of both hands.
- Visual-Motor Integration: This 72-item subtest measures a child's ability to use his or her visual perceptual skills to perform complex eye-hand coordination tasks such as reaching and grasping for an object, building with blocks, and copying designs.
Fine Motor Quotient: This composite is a combination of the results of the subtests that measure the use of the small muscle systems: Grasping (all ages), Visual-Motor Integration (all ages).
Gross Motor Quotient: This composite is a combination of the results of the subtests that measure the use of the large muscle systems:
- Reflexes (birth-11 months only)
- Stationary (all ages)
- Locomotion (all ages)
- Object Manipulation (12 months and older)
Total Motor Quotient: This composite is formed by a combination of the results of the gross and fine motor subtests. Because of this, it is the best estimate of overall motor abilities.
Psychometrically, the second edition of the PDMS has improved in the following ways:
- All of the new normative data were collected in the Winter of 1997 and the Spring of 1998.
- Characteristics of the normative sample relative to geography, gender, race, and other critical variables are the same as those reported in the Statistical Abstract of the United States (U.S. Bureau of the Census, 1997) and are therefore representative of the current U.S. population.
- The normative information has been stratified by age.
- Studies showing the absence of gender and racial bias have been added.
- Reliability coefficients were computed for subgroups of the normative sample (e.g., individuals with motor disabilities, African Americans, Hispanic Americans, females, and males) as well as for the entire normative sample.
- New validity studies have been conducted; special attention has been devoted to showing that the test is valid for a wide variety of subgroups as well as for the general population.
- Each item was evaluated using both conventional item analyses to choose “good” statistical items and the new differential item functioning analyses to find biased items.
The second edition of the PDMS has also improved or added the following user-friendly components:
- The new Profile/Summary Forms enable the examiner to record the child's PDMS-2 scores and graphically display the child's performance in two formats. First, the examiner records the child's name and calculates his or her age. Second, the PDMS-2 raw scores, percentiles, age equivalents, and standard scores for subtests and composites are recorded. Third, PDMS-2 standard scores for the subtests and composites can be plotted on the Profile section to get a gross estimate of the child's strengths and weaknesses. Finally, each item on which the child met the criterion for mastery during testing is marked on the Profile of Item Mastery section. This enables the examiner to compare the child's performance on the items he or she has mastered with that of the normative sample.
- The new Examiner Record Booklets contain all of the items to be given to the child. Booklets contain abbreviated instructions for administering items once the examiner is thoroughly familiar with the more detailed instructions found in the Illustrated Guide for Administering and Scoring the PDMS-2 Items. The booklets contain clearly marked entry points to be used to locate the beginning item for each subtest.
- descriptions of every item in the PDMS-2. The items are referenced by number within each subtest and each item description includes: (a) the age at which 50% of the children in the normative sample have mastered the item, (b) the position the child should be in when the item is administered, (c) the stimulus (if needed) for presenting the item, (d) the procedure used to test the item, (e) the criterion used to score the item, and (f) the illustration of a child performing the item.
- The Peabody Motor Activities Program (P-MAP) is the instruction/treatment program for the PDMS-2. It contains units organized developmentally by skill area. After a child's motor skills have been assessed and the examiner has completed all sections of the Profile/ Summary Form, the examiner selects units from the P-MAP to use to facilitate the child's development in specific skill areas.
- The new Peabody Motor Development Chart provides the examiner with a convenient reference for the motor skills measured by the PDMS-2 and the ages at which 50% of the normative sample performed the skill. Each of the subtests is represented along with numerous illustrations of children demonstrating the behaviors described in the text.
- PC, Mac™, and iPad™ compatible PDMS-2 Online Scoring and Report System (includes 5 licenses) reduces scoring and reporting time and errors by (a) calculating basals and ceilings on item-level data; (b) converting PDMS-2 item scores or subtest raw scores into standard scores, percentile ranks, and age equivalents; (c) generating composite quotients; (d) comparing PDMS-2 subtest and composite performance to identify significant intra-individual differences; and (e) providing a printed report of the student's identifying information and PDMS-2 performance, including short-term and long-term treatment goals and objectives.