Newby P K, Weismayer Christoph, Akesson Agneta, Tucker Katherine L, Wolk Alicja
Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
J Nutr. 2006 Mar;136(3):626-33. doi: 10.1093/jn/136.3.626.
Limited data exist on the reproducibility of food patterns measured by factor analysis as well as on the use of stability of patterns over time. Our primary objective was to explore the long-term stability of food patterns derived by confirmatory factor analysis among 33,840 women participating in the Swedish Mammography Cohort. Our secondary objective was to compare factor solutions from confirmatory factor analysis with those derived by use of exploratory factor analysis. Diet was assessed by a food frequency questionnaire in 1987 and 1997, and food patterns were derived by the use of exploratory and confirmatory factor analysis. We observed four major food patterns (Healthy, Western/Swedish, Alcohol, and Sweets) at both time points. Correlations between confirmed food patterns in 1987 and 1997 were 0.37 for the Healthy pattern, 0.27 for the Western/Swedish pattern, 0.54 for the Alcohol pattern, and 0.44 for the Sweets pattern (P < 0.0001 for all associations). Patterns derived by the use of exploratory factor analysis were strongly associated with those derived by the use of confirmatory factor analysis (r >/= 0.90, P < 0.0001, for all associations). The patterns derived in this study were similar to those derived in other studies, indicating reproducibility of food patterns across populations. Our study suggests that food patterns measured by the use of confirmatory factor analysis are reproducible over time, and weaker correlations observed may reflect natural changes in eating behavior, the food supply, and/or perceptions of what is considered healthy. Testing whether patterns measured over a long time period can be used in analytic studies is the next step in assessing the validity of this method.
关于通过因子分析测量的食物模式的可重复性以及这些模式随时间的稳定性，现有数据有限。我们的主要目标是探讨在参与瑞典乳腺X线摄影队列研究的33840名女性中，通过验证性因子分析得出的食物模式的长期稳定性。我们的次要目标是将验证性因子分析的因子解与通过探索性因子分析得出的因子解进行比较。在1987年和1997年通过食物频率问卷评估饮食情况，并通过探索性和验证性因子分析得出食物模式。在两个时间点我们都观察到四种主要的食物模式（健康型、西方/瑞典型、酒精型和甜食型）。1987年和1997年确定的食物模式之间的相关性，健康型为0.37，西方/瑞典型为0.27，酒精型为0.54，甜食型为0.44（所有关联的P<0.0001）。通过探索性因子分析得出的模式与通过验证性因子分析得出的模式密切相关（所有关联的r≥0.90，P<0.0001）。本研究得出的模式与其他研究得出的模式相似，表明食物模式在不同人群中具有可重复性。我们的研究表明，通过验证性因子分析测量的食物模式随时间具有可重复性，观察到的较弱相关性可能反映了饮食行为、食物供应和/或对健康观念的自然变化。测试在长时间内测量的模式是否可用于分析研究是评估该方法有效性的下一步。
