Reliability of routine clinical measurements of neonatal circumferences and research measurements of neonatal skinfold thicknesses: findings from the Born in Bradford study.

Assessing neonatal size reliably is important for research and clinical practice. The aim of this study was to examine the reliability ofroutine clinical measurements of neonatal circumferences and of skinfold thicknesses assessed for research purposes. Allmeasurements were undertaken on the same population of neonates born in a large maternity unit in Bradford, UK. Technical error of measurement (TEM), relative TEM and the coefficient of reliability are reported. Intra-observer TEMs for routine circumferencemeasurements were all below 0.4 cm and were generally within ± 2-times the mean. Inter-observer TEM ranged from 0.20 to 0.36 cm for head circumference, 0.19 to 0.39 cm for mid upper arm circumference and from 0.39 to 0.77 cm for abdominal circumference. Intra and inter-observer TEM for triceps skinfold thickness ranged from 0.22 to 0.35 mm and 0.15 to 0.54 mm, respectively. Subscapularskinfold thickness TEM values were 0.14 to 0.25 mm for intra-observer measurements and 0.17 to 0.63 mm for inter-observermeasurements. Relative TEM values for routine circumferences were all below 4.00% but varied between 2.88% and 14.23% forresearch skinfold measurements. Reliability was mostly between 80% and 99% for routine circumference measurements and ≥ 70% for most research skinfold measurements. Routine clinical measurements of neonatal circumferences are reliably assessed in Bradford. Assessing skinfolds in neonates has variable reliability, but on the whole is good. The greater intra-observer, compared with inter-observer, reliability for both sets of measurements highlights the importance of having a minimal number of assessors whenever possible.