Bohlscheid-Thomas S, Hoting I, Boeing H, Wahrendorf J
Division of Epidemiology, German Cancer Research Centre, Heidelberg, Germany.
Int J Epidemiol. 1997;26 Suppl 1:S71-81. doi: 10.1093/ije/26.suppl_1.s71.
For use in the German part of the European Prospective Investigation into Cancer and Nutrition (EPIC) a self-administered, optically readable food frequency questionnaire (FFQ) was developed to assess individuals' usual food and nutrient intake over the past year. The food list comprised 158 food items for which the typical portion size, the consumption frequency (1-6 times) and the time period (day, week, month, or year) were requested. This paper reports the results of the reproducibility and relative validity of nutrient intakes obtained by this instrument.
The study was carried out from October 1991 to October 1992. During this period, 104 men and women, aged 35-64 years, completed a 24-hour recall once a month, and the FFQ in the middle and at the end of this study. A short questionnaire on global consumption patterns was used to adjust the food consumption frequency given in the FFQ.
Reproducibility correlations varied from 0.59 for saturated fat to 0.88 for alcohol, with most values falling between 0.60 and 0.70. Energy-adjustment decreased the observed correlations for all nutrients. Correlations between nutrient intake values from the 12-day average of dietary recalls and the FFQ corrected for food consumption frequency ranged from 0.42 for polyunsaturated fat to 0.88 for alcohol, followed by 0.65 for dietary fibres. After de-attenuation and energy-adjustment the range of correlations was somewhat wider (0.43-0.75, without alcohol). With regard to classification, on average, 36% of subjects fell into the same quintile, and 75% into within-one quintile when classified by the frequency-corrected FFQ compared to the quintiles based on recalled data.
In summary, the newly developed FFQ showed fairly good reproducibility and relative validity for most evaluated nutrients. The between-subject variation of nutrients in the German cohort (including the participants from East Germany) is likely to be greater than that among the subjects of the pilot phase. A revised version of the FFQ corrected for food consumption frequency is used in the EPIC study.
为用于欧洲癌症与营养前瞻性调查（EPIC）的德国部分，开发了一种自我管理的、光学可读的食物频率问卷（FFQ），以评估个体在过去一年中的日常食物和营养摄入量。食物清单包含158种食物，要求填写典型份量、消费频率（1 - 6次）以及时间段（天、周、月或年）。本文报告了通过该工具获得的营养摄入量的重复性和相对有效性结果。
研究于1991年10月至1992年10月进行。在此期间，104名年龄在35 - 64岁的男性和女性每月完成一次24小时膳食回顾，并在研究中期和末期完成FFQ。使用一份关于总体消费模式的简短问卷来调整FFQ中给出的食物消费频率。
重复性相关性从饱和脂肪的0.59到酒精的0.88不等，大多数值在0.60至0.70之间。能量调整降低了所有营养素的观察相关性。膳食回顾12天平均值的营养摄入量值与根据食物消费频率校正后的FFQ之间的相关性，从多不饱和脂肪的0.42到酒精的0.88不等，膳食纤维为0.65。去衰减和能量调整后，相关性范围稍宽（0.43 - 0.75，不包括酒精）。关于分类，平均而言，与基于回顾数据的五分位数相比，经频率校正的FFQ进行分类时，36%的受试者落入相同五分位数，75%落入相邻五分位数。
总之，新开发的FFQ对大多数评估营养素显示出相当好的重复性和相对有效性。德国队列（包括东德参与者）中营养素的个体间差异可能大于试点阶段的受试者。EPIC研究中使用了根据食物消费频率校正后的FFQ修订版。
