Can you average out the subtests on PDMS to get an overall score?

No, you cannot simply average the subtest scores on the Peabody Developmental Motor Scales (PDMS-2) to get a meaningful overall score. The PDMS-2 provides separate scores for Gross Motor and Fine Motor, and each of those has subtests which contribute to the overall scores. Averaging the individual subtest scores ignores the weighting and standardization inherent in the test's design.

The PDMS-2 is designed to provide standard scores, percentile ranks, and age equivalents for both the Gross Motor Quotient (GMQ) and Fine Motor Quotient (FMQ). These quotients are the appropriate overall scores to use, reflecting the psychometric properties of the test. They are based on the combined performance across the relevant subtests and are norm-referenced, allowing for comparisons to other children of the same age. Simply averaging the subtest raw scores doesn't provide this crucial normative comparison.