1USDA/ARS Children's Nutrition Research Center,Department of Pediatrics,Baylor College of Medicine,1100 Bates Street,Houston,TX 77030,USA.
2Department of Neurological Surgery,University of Pittsburgh,Pittsburgh,PA,USA.
Public Health Nutr. 2019 May;22(7):1153-1159. doi: 10.1017/S1368980017004293. Epub 2018 Feb 12.
The eButton takes frontal images at 4s intervals throughout the day. A three-dimensional manually administered wire mesh procedure has been developed to quantify portion sizes from the two-dimensional images. The present paper reports a test of the inter-rater reliability and validity of use of the wire mesh procedure.
Seventeen foods of diverse shapes and sizes served on plates, bowls and cups were selected to rigorously test the portion assessment procedure. A dietitian not involved in inter-rater reliability assessment used standard cups to independently measure the quantities of foods to generate the 'true' value for a total of seventy-five 'served' and seventy-five smaller 'left' images with diverse portion sizes.
The images appeared on the computer to which the digital wire meshes were applied.
Two dietitians and three engineers independently estimated portion size of the larger ('served') and smaller ('left') images for the same foods.
The engineers had higher reliability and validity than the dietitians. The dietitians had lower reliabilities and validities for the smaller more irregular images, but the engineers did not, suggesting training could overcome this limitation. The lower reliabilities and validities for foods served in bowls, compared with plates, suggest difficulties with the curved nature of the bowls.
The wire mesh procedure is an important step forward in quantifying portion size, which has been subject to substantial self-report error. Improved training procedures are needed to overcome the identified problems.
eButton 以 4 秒的间隔拍摄一整天的正面图像。现已开发出一种手动的三维金属网格程序，用于从二维图像中定量分析食物份量。本文报告了对金属网格程序使用的组内一致性和有效性的测试。
选择了 17 种不同形状和大小的食物，放在盘子、碗和杯子中，以严格测试部分评估程序。一位不参与组内一致性评估的营养师使用标准杯子独立测量食物的量，以生成总共 75 个“供应”和 75 个较小的“剩余”图像的“真实”值，这些图像具有不同的份量。
图像出现在应用数字金属网格的计算机上。
两位营养师和三位工程师独立地估计了相同食物的较大（“供应”）和较小（“剩余”）图像的份量。
工程师的可靠性和有效性均高于营养师。对于较小的、不规则的图像，营养师的可靠性和有效性较低，但工程师则没有，这表明培训可以克服这一限制。与盘子相比，碗中食物的可靠性和有效性较低，这表明碗的弯曲性质存在困难。
金属网格程序是量化份量的重要一步，份量的报告存在大量的自我报告误差。需要改进培训程序以克服已确定的问题。
