Gross Motor Function Classification System (GMFCS) 
This classification system, for children 2 to 18 years of age, is a measure of mobility function.
I. Walks unimpeded without assistive devices; has impairments in advanced gross motor skills.
II. Walks mostly without assistive devices; uses railings for stairs; has difficulty walking outdoors on uneven terrain or in the community.
III. Walks with assistive devices such as crutches or a walker; may use wheelchair for long distances.
IV. Limited self-mobility; transported using wheelchair or uses power chair as primary mobility; may walk for short distances with assistance.
V. Total dependence on others for wheelchair mobility; if using power chair, requires extensive adaptation.
Updated classification schemes with clarifications and revisions and classifications for younger children can be obtained from the CanChild Centre. http://www.netchild.nl/pdf/herziene-gmfcs-2007-met-uitbr-voor-leeftijd12-18%20jaar,gmfcs-er-engels.pdf [CanChild Centre: GMFCS expanded and revised] GMFCS handouts for different age-groups are also available. http://www.rch.org.au/emplibrary/ortho/GMFCSER_6-12.pdf [GMFCS handout: 6-12 years] http://www.rch.org.au/emplibrary/ortho/GMFCSER_12-18.pdf [GMFCS handout: 12-18 years]