Analysis to Determine Which Items Qualify for the Motor Observations

For the item selection we looked at the two most important psychometric qualities of the test: the validity and the reliability.

See table 1.

Developmental factors:

On the far left is the list of items. The next two columns on the left show the percentage of children in our sample at age 5 years 11 months and 8 years 0 months to 11 years --11 months who received a score of a 5 or 4 on each item. These scores are considered excellent and good scores respectively. We were interested in retaining items which could be performed adequately by 75% of our sample, especially in the oldest age group. The developmental trends per item were also evaluated.


For validity we evaluated the differences between our norm group’s individual item scores and those of the children in sensory integration therapy. This is to be seen in the middle column. It was necessary to have P< .05 for the item to be included in our final selection.


Intra class correlations are seen in the second column from the right. In this reliability test we scored 23 children twice during a live Motor Observation. We chose r > .70 and a minimum of .050 for reliability. Out of our final 36 items, 32 items had r > .70.

From our original items of 71, 36 items with high psychometric qualities remained after the item reduction using these criteria.