Mayer-Davis E J, Vitolins M Z, Carmichael S L, Hemphill S, Tsaroucha G, Rushing J, Levin S
Department of Epidemiology and Biostatistics, School of Public Health, University of South Carolina, Columbia 29208, USA.
Ann Epidemiol. 1999 Jul;9(5):314-24. doi: 10.1016/s1047-2797(98)00070-2.
There is limited support for the validity and reproducibility of dietary assessment in culturally diverse populations. The goal of this study was to evaluate the comparative validity and reproducibility of a Food Frequency Questionnaire (FFQ) used in the observational, multi-cultural Insulin Resistance Atherosclerosis Study (IRAS).
Women (n = 186) were approximately equally distributed by ethnicity from one urban center (African Americans and non-Hispanic whites) and one rural center (Hispanics and non-Hispanic whites). The IRAS FFQ was modified from the National Cancer Institute Health Habits and History Questionnaire to include ethnic and regional foods. Validity was assessed by comparing dietary values, including supplements, obtained from the FFQ to the average intake estimated from a series of 8 24-hour dietary recalls collected by telephone over the same 1-year period. Reproducibility was assessed among women who reported no change in their usual diet (n = 133) by comparing data from the original IRAS FFQ (in-person) with the FFQ administered for the validity study (two to four years later, by telephone).
Correlation coefficients for validity were statistically significant for most nutrients (mean r = 0.62 urban non-Hispanic white, 0.61 rural non-Hispanic whites, 0.50 African American, 0.41 Hispanic) and did not differ among subgroups of obesity or diabetes status. The median correlation coefficient for the total sample was 0.49. Correlations were lower for women with less than 12 years of education (mean r = 0.30; median r = 0.25). The lower correlations among Hispanics was largely explained by the lower educational attainment in that sample. For reproducibility, the mean correlation for nutrients evaluated was r = 0.62 (median r = 0.63) and did not differ for subgroups.
Although educational attainment must be considered, the IRAS FFQ appears to be reasonably valid and reliable in a diverse cohort.
在文化多元的人群中，饮食评估的有效性和可重复性的支持有限。本研究的目的是评估在观察性、多文化的胰岛素抵抗动脉粥样硬化研究（IRAS）中使用的食物频率问卷（FFQ）的比较有效性和可重复性。
来自一个城市中心（非裔美国人和非西班牙裔白人）和一个农村中心（西班牙裔和非西班牙裔白人）的女性（n = 186）按种族大致平均分布。IRAS FFQ是从美国国立癌症研究所健康习惯和病史问卷修改而来，以纳入民族和地区食物。通过将从FFQ获得的饮食值（包括补充剂）与在同一1年期间通过电话收集的一系列8次24小时饮食回忆估计的平均摄入量进行比较来评估有效性。通过比较原始IRAS FFQ（面对面）的数据与为有效性研究管理的FFQ（两到四年后，通过电话），在报告其日常饮食无变化的女性（n = 133）中评估可重复性。
大多数营养素的有效性相关系数具有统计学意义（城市非西班牙裔白人平均r = 0.62，农村非西班牙裔白人平均r = 0.61，非裔美国人平均r = 0.50，西班牙裔平均r = 0.41），并且在肥胖或糖尿病状态的亚组之间没有差异。总样本的中位数相关系数为0.49。受教育年限少于12年的女性的相关性较低（平均r = 0.30；中位数r = 0.25）。西班牙裔中较低的相关性在很大程度上是由该样本中较低的教育程度所解释的。对于可重复性，评估的营养素的平均相关性为r = 0.62（中位数r = 0.63），并且在亚组之间没有差异。
尽管必须考虑教育程度，但IRAS FFQ在不同队列中似乎具有合理的有效性和可靠性。
