Particular emphasis in creating and maintaining the GMFCS scale rests on evaluating sitting, walking, and wheeled mobility.
Distinctions between levels are based on functional abilities; the need for walkers, crutches, wheelchairs, or canes / walking sticks; and to a much lesser extent, the actual quality of movement.
GMFCS is now the standard in both North America and Western Europe for mobility assessment and ambulatory ability prediction for cerebral palsy.
The examination is done using the "Gross Motor Function Measure", (GMFM), a set of 66 sitting (truncal control) as well as walking exercises conducted during the GMFM assessment that help the specialist classify the person into one of the system's five levels or, sometimes, to classify the person as "in between" two different levels.
• Can walk indoors and outdoors and climb stairs without using hands for support • Can perform usual activities such as running and jumping • Has decreased speed, balance and coordination • Can climb stairs with a railing • Has difficulty with uneven surfaces, inclines or in crowds • Has only minimal ability to run or jump • Walks with assistive mobility devices indoors and outdoors on level surfaces • May be able to climb stairs using a railing • May propel a manual wheelchair and need assistance for long distances or uneven surfaces • Walking ability severely limited even with assistive devices • Uses wheelchairs most of the time and may propel own power wheelchair • Standing transfers, with or without assistance • Has physical impairments that restrict voluntary control of movement • Ability to maintain head and neck position against gravity restricted • Impaired in all areas of motor function • Cannot sit or stand independently, even with adaptive equipment • Cannot independently walk but may be able to use powered mobility The GMFCS has been used to describe study samples in terms of the number of children in each band.