Maternal and Child Health Bureau ~ 7
3. Measurement considerations for children with special needs
The reference data used to develop the CDC growth charts were drawn from a nationally representative sample. These reference data are not specific for children with special health care needs. Thus, the clinician who uses the CDC growth charts to interpret the growth of a child with special health care needs must understand the potential influence of the specific condition on growth and identify reasons the child's growth might be different than that of other children.
Most important in growth assessment is consistency, using accurate measurement techniques, repeating the measurements, checking for accuracy, and, above all, plotting a series of measurements over time. (For more information, see the modules about Accurately Weighing and Measuring Infants, Children, and Adolescents: Equipment; Technique; and Developing and Rating Your Technique.
Because of their conditions, some children with special needs may be difficult to measure. Problems may include an inability to stand, contractures, scoliosis, lack of head and trunk control, and the need to wear braces. Generally, equipment in primary care clinics may not be adaptable for children with special needs. Conditions that may present problems in measurement are those associated with physical disabilities like cerebral palsy (where contractures interfere with accuracy), and spina bifida (where the child may not be able to stand erect or has scoliosis, which makes measuring stature very difficult).
Children with some conditions, such as Rett syndrome or Prader-Willi syndrome, may present no measurement problems with the available anthropometric equipment, but the resulting data may be difficult to interpret because of altered growth potential.
In the remainder of this section, some potential measurement problems of children with special health care needs are discussed and alternative measurements are reviewed.
Measures of Stature and Length
Children unable to stand should be measured on a recumbent board. Scoliosis and leg contractures decrease the accuracy of the length measurement. Alternative measurements can be used to assess linear growth, including:
crown-rump length and sitting height
upper arm length
lower leg length
Crown-rump length and sitting height Sitting height and crown-rump length are sometimes used in place of stature and length when a child is unable to stand, but can sit erect.
Crown-rump length Crown-rump length is measured using a recumbent length board.
Equipment: recumbent length board