由于人口饮食变化，食物频率调查问卷需要随着时间的推移进行更新，这对前瞻性研究中持续测量饮食提出了分析挑战。在一项正在进行的北美孕前研究中，我们比较了国家癌症研究所基于网络的饮食史问卷（DHQ，III 与 II）的两个版本中营养素之间的可靠性和一致性。我们邀请了 51 名年龄在 21 岁至 45 岁之间的美国女性参与者，以随机顺序在两周内完成两个 DHQ 版本。我们比较了两个 DHQ 版本中的 30 种营养素，并使用组内相关系数 (ICC) 计算了人内可靠性。生成 Bland-Altman 图和 95% 一致性限度 (LOA)，以评估 DHQ 版本之间的营养一致性。我们观察到碳水化合物和胆固醇的能量百分比可靠性最高（ICC：0.88；95% CI：0.80-0.93），蛋白质和维生素 D 的能量百分比可靠性最低（ICC：0.56；95% CI：0.34-0.72）。在群体层面，所有营养素在 LOA 内的观察结果最多。 Bland-Altman 图显示了 DHQ 之间对蛋白质、脂肪、单不饱和脂肪和维生素 D 的评估差异。其余营养素表现出良好的一致性和良好至中等的可靠性。某些营养素可能需要调整和校准分析，然后才能在 DHQ 版本之间互换使用。© 作者 2024。由牛津大学出版社代表约翰·霍普金斯大学彭博公共卫生学院出版。版权所有。如需权限，请发送电子邮件至：journals.permissions@oup.com。

Food frequency questionnaires require updating over time, due to population changes in diet, posing analytical challenges in consistently measuring diet in prospective studies. We compared reliability and agreement between nutrients in two versions of the National Cancer Institute's web-based Diet History Questionnaire (DHQ, III vs. II) in an ongoing North American preconception study. We invited 51 consecutively-enrolled U.S. female participants aged 21-45 years to complete both DHQ versions within a 2-week period, in a randomized order. We compared 30 nutrients from both DHQ versions and calculated within-person reliability using intraclass correlation coefficients (ICCs). Bland-Altman plots and 95% limits of agreement (LOA) were generated to assess nutrient agreement between DHQ versions. We observed highest reliability in percent energy from carbohydrates and cholesterol (ICCs: 0.88; 95% CI: 0.80-0.93) and lowest for percent energy from protein and vitamin D (ICCs: 0.56; 95% CI: 0.34-0.72). At the group level, all nutrients had most observations within the LOA. Bland-Altman plots showed assessment differences between DHQs for protein, fat, monounsaturated fat, and vitamin D. The remaining nutrients showed good agreement and good-to-moderate reliability. Some nutrients may require adjustment and calibration analysis before using them interchangeably across DHQ versions.© The Author(s) 2024. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.