lifting each foot to touch a stool (No. 12), standing in
tandem stance (No. 13), and standing on one leg (No. 14).
During the initial development of the BBS, Berg stated that,
“the lack of an item that requires a postural response to an
external stimulus or uneven support surface. . .will likely
limit the utility of the scale when assessing very active
persons with minimal deficits.”8 Items on theGMFMcould
be considered as more challenging than items on the BBS.
However, items on the BBS and the GMFM were not discrete
enough to enable a therapist to distinguish between
the balance abilities of children with no motor impairment
and children with spastic hemiplegia by using test scores.
After functional classification using the GMFCS, the
ability to use scores on both the BBS and the GMFM to
distinguish among the groups was identical. Functional
classification resulted in more homogeneous groups in
terms of balance abilities. Despite an improved ability to
distinguish among the groups, it was still not possible to
differentiate between children in Level I and children with
no motor impairment by using test scores. This finding
may be due to a lack of items on either test that are discrete
enough to identify subtle deficits in balance in children
who have a mild motor impairment. Items that are more
challenging to balance, such as items requiring speed, or
movement over uneven terrain, may distinguish between
children in Level I and children with no motor impairment.
Neither test has such items.