Variability of energy-consumption measures in children with cerebral palsy

Oxygen consumption measurements made on five repeated rests from. five chil dren with cerebral palsy (CP) and five nondisabled children of similar age and size were collected using the Cosmed K2 (Cosmed, Rome, Italy) oxygen-an alysis system at free-walking velocity. Oxygen cost, oxygen consumption, an d physiological cost index (PCI) were measured. There were no statistically significant differences in the percentage of variability of oxygen cost, o xygen consumption, or PCI between the disabled and nondisabled populations. Oxygen cost was the most reliable oxygen-use measurement with an average p ercentage of variability of 13.2% for the CP population and 13.9% for the n ondisabled population. Physiological cost index was found be the least reli able measurement with the average percentages of variabilities of the disab led and nondisabled populations of 20.3 and 20.5%, respectively. Thus becau se of oxygen cost's relatively low variability, it was the most sensitive m easurement of change in gait efficiency.