The purpose of this study is to try to correlate vitamin D dosing and dosing adjustment with Vitamin D levels, measure affects of seizure medications on levels as well as pathologic fractures and bone density in severely cognitively impaired, non-mobile children and adolescents with CP.

Inclusion Criteria:

• Recorded vitamin D supplementation dose (i.e. prescribed diet and any additional sources of vitamin D) with at least two serum vitamin D concentrations recorded in the medical chart from January 1, 2008 to June 30, 2013.
• Resident of HLCCD since 2008

Exclusion Criteria:

• No vitamin D levels recorded.
• History of hyperthyroidism or parathyroid pathology.
• Short gut syndrome that requires TPN.
• Poor medical documentation.
• Heritable disorders that affect vitamin D levels such as Pseudovitamin D deficiency rickets, Vitamin D resistant rickets, autosomal dominant hypophosphatemic rickets and X-linked hypophosphatemic rickets

Severely cognitively impaired, non-mobile children and young adults who are residents at long-term care facility