Reliability of anthropometric measurements in children with special needs.

OBJECTIVE: To determine the reliability of anthropometric and body composition measurements in children with special needs.

DESIGN: Observational study.

SETTING: Specialist support schools (primary and secondary) in Manchester, UK.

PARTICIPANTS: 53 children with moderate-to-severe learning disability; 30 non-standers (14 boys) and 23 standers (15 boys). Mean ages were 11 years (range 3-20) for non-standers and 12.4 years (range 8-19) for standers.

MEASURES: Anthropometric measures included: height/length, segmental measures, weight, skinfolds, body circumferences and body composition estimated from bioelectrical impedance analysis (BIA). These were measured twice, 2-4 weeks apart.

MAIN OUTCOME MEASURES: Reliability was assessed using the technical error of measurement (TEM).

RESULTS: The TEM for height and supine length was 0.55 cm for standers and 2.47 cm for non-standers, respectively. For non-standers, the TEMs for knee height and tibial length were 0.81 and 1.57 cm, respectively. The TEM for weight was 0.55 kg for standers and 0.75 kg for non-standers. For skinfold thickness, the TEM was smaller for non-standers than standers. The TEM for mid-upper arm circumference for standers and non-standers was 0.91 and 0.82 cm, respectively. The TEM for BIA in standers and non-standers was 34.7 and 54.1 Ω, respectively. Some measurements, including waist circumferences, were difficult to obtain reliably.

CONCLUSIONS: Anthropometric and body composition measurements were feasible to obtain in children with special needs. However, the reliability of these measures differs between non-standers and standers and should be considered when choosing appropriate measures.