USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, 1100 Bates Street, Houston, TX 77030-2600, USA.
Public Health Nutr. 2011 Mar;14(3):418-25. doi: 10.1017/S1368980010002193. Epub 2010 Nov 15.
To test the effect of image size and presence of size cues on the accuracy of portion size estimation by children.
Children were randomly assigned to seeing images with or without food size cues (utensils and checked tablecloth) and were presented with sixteen food models (foods commonly eaten by children) in varying portion sizes, one at a time. They estimated each food model's portion size by selecting a digital food image. The same food images were presented in two ways: (i) as small, graduated portion size images all on one screen or (ii) by scrolling across large, graduated portion size images, one per sequential screen.
Laboratory-based with computer and food models.
Volunteer multi-ethnic sample of 120 children, equally distributed by gender and ages (8 to 13 years) in 2008-2009.
Average percentage of correctly classified foods was 60·3 %. There were no differences in accuracy by any design factor or demographic characteristic. Multiple small pictures on the screen at once took half the time to estimate portion size compared with scrolling through large pictures. Larger pictures had more overestimation of size.
Multiple images of successively larger portion sizes of a food on one computer screen facilitated quicker portion size responses with no decrease in accuracy. This is the method of choice for portion size estimation on a computer.
测试图像大小和大小提示的存在对儿童准确估计份量的影响。
儿童被随机分配到有或没有食物大小提示（餐具和方格桌布）的图像中，并一次呈现十六个食物模型（儿童常吃的食物），大小不一。他们通过选择数字食物图像来估计每个食物模型的份量。相同的食物图像以两种方式呈现：（i）在一个屏幕上显示所有小的、分级的份量图像，或（ii）在一个大的、分级的份量图像上滚动，每个图像显示在一个连续的屏幕上。
基于实验室的计算机和食物模型。
2008-2009 年间，志愿者的多民族样本中有 120 名儿童，按性别和年龄（8 至 13 岁）平均分配。
正确分类食物的平均百分比为 60.3%。任何设计因素或人口特征都没有差异。与滚动大图片相比，一次在屏幕上显示多个小图片估计份量的时间缩短了一半。较大的图片会导致更大的尺寸估计误差。
在一个计算机屏幕上同时显示多个逐渐增大的食物份量的图像可以更快地做出份量大小的反应，且准确性不会降低。这是在计算机上进行份量估计的首选方法。
