Piwoz E G, Creed de Kanashiro H, Lopez de Romaña G, Black R E, Brown K H
Department of International Health, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, MD 21205.
Eur J Clin Nutr. 1994 May;48(5):333-40.
(i) To examine the components of variation in infant energy intake. (ii) To calculate the precision of estimates of energy intake from different sources. (iii) To estimate the number of dietary studies required to estimate true energy intake with varying degrees of precision.
Energy intakes were determined from monthly 12-h observations with test-weighing of breastmilk and all foods consumed. Variance components were evaluated by pooling results of studies performed when infants were 1-4, 5-8 and 9-12 months old.
Pueblo Joven Huáscar, a low-income, peri-urban community in Lima, Peru.
124 infants who were enrolled at birth and followed monthly.
Within-to-between infant variance ratios were > 1.0 for total energy and energy from solid foods, and < 1.0 for energy from breast- and non-human milks during the 4-month periods examined. Total energy and energy from breastmilk were estimated to within 13-24% of infants' true intake. Non-breastmilk energy was estimated to within 19-143% of true intake. Four dietary studies per age period are required to estimate total energy and breastmilk energy consumption with 20-30% precision. At least 16 studies are required to estimate infants' average energy intake from solid foods from 5-8 months with 30% precision.
The degree of precision achieved during assessment of infants' usual energy intake changes with age and composition of the diet. Thus, the number of dietary studies required to obtain a fixed level of precision differs according to these characteristics.
（i）研究婴儿能量摄入的变异成分。（ii）计算来自不同来源的能量摄入估计值的精度。（iii）估计以不同精度估计真实能量摄入所需的膳食研究数量。
通过每月12小时的观察并对母乳和所有摄入食物进行称重来确定能量摄入量。通过汇总婴儿1 - 4个月、5 - 8个月和9 - 12个月大时进行的研究结果来评估方差成分。
秘鲁利马一个低收入的城郊社区普韦布洛·霍文·瓦斯卡尔。
124名出生时登记并每月随访的婴儿。
在所研究的4个月期间，婴儿内部与婴儿之间的方差比对于总能量和来自固体食物的能量大于1.0，对于来自母乳和非母乳的能量小于1.0。估计总能量和来自母乳的能量在婴儿真实摄入量的13% - 24%以内。估计非母乳能量在真实摄入量的19% - 143%以内。每个年龄段需要四项膳食研究来以20% - 30%的精度估计总能量和母乳能量消耗。至少需要16项研究来以30%的精度估计5 - 8个月婴儿从固体食物中摄入的平均能量。
评估婴儿日常能量摄入时所达到的精度程度随年龄和饮食组成而变化。因此，根据这些特征，获得固定精度水平所需的膳食研究数量也不同。
