Hu Mengyao, Gremel Garrett W, Kirlin John A, West Brady T
Michigan Program in Survey Methodology, Institute for Social Research, University of Michigan-Ann Arbor, Ann Arbor, MI; and
Michigan Program in Survey Methodology, Institute for Social Research, University of Michigan-Ann Arbor, Ann Arbor, MI; and.
J Nutr. 2017 May;147(5):964-975. doi: 10.3945/jn.116.240697. Epub 2017 Mar 15.
Food acquisition diary surveys are important for studying food expenditures, factors affecting food acquisition decisions, and relations between these decisions with selected measures of health (e.g., body mass index, self-reported health). However, to our knowledge, no studies have evaluated the errors associated with these diary surveys, which can bias survey estimates and research findings. The use of paradata, which has been largely ignored in previous literature on diary surveys, could be useful for studying errors in these surveys. We used paradata to assess survey errors in the National Household Food Acquisition and Purchase Survey (FoodAPS). To evaluate the patterns of nonresponse over the diary period, we fit a multinomial logistic regression model to data from this 1-wk diary survey. We also assessed factors influencing respondents' probability of reporting food acquisition events during the diary process by using logistic regression models. Finally, with the use of an ordinal regression model, we studied factors influencing respondents' perceived ease of participation in the survey. As the diary period progressed, nonresponse increased, especially for those starting the survey on Friday (where the odds of a refusal increased by 12% with each fielding day). The odds of reporting food acquisition events also decreased by 6% with each additional fielding day. Similarly, the odds of reporting ≥1 food-away-from-home event (i.e., meals, snacks, and drinks obtained outside the home) decreased significantly over the fielding period. Male respondents, larger households, households that eat together less often, and households with frequent guests reported a significantly more difficult time getting household members to participate, as did non-English-speaking households and households currently experiencing difficult financial conditions. Nonresponse and underreporting of food acquisition events tended to increase in the FoodAPS as data collection proceeded. This analysis of paradata available in the FoodAPS revealed these errors and suggests methodologic improvements for future food acquisition surveys.
食物获取日记调查对于研究食物支出、影响食物获取决策的因素以及这些决策与选定健康指标（如体重指数、自我报告的健康状况）之间的关系非常重要。然而，据我们所知，尚无研究评估与这些日记调查相关的误差，这些误差可能会使调查估计和研究结果产生偏差。在以往关于日记调查的文献中大多被忽视的辅助数据的使用，可能有助于研究这些调查中的误差。我们使用辅助数据来评估全国家庭食物获取与购买调查（FoodAPS）中的调查误差。为了评估日记记录期间无回应的模式，我们对这项为期1周的日记调查的数据拟合了多项逻辑回归模型。我们还通过使用逻辑回归模型评估了在日记记录过程中影响受访者报告食物获取事件概率的因素。最后，我们使用有序回归模型研究了影响受访者认为参与调查难易程度的因素。随着日记记录期的推进，无回应情况增加，尤其是那些在周五开始调查的人（每增加一个调查日，拒绝的几率增加12%）。每增加一个调查日，报告食物获取事件的几率也会降低6%。同样，在调查期间，报告≥1次外出就餐事件（即在家外获得的餐食、小吃和饮料）的几率显著下降。男性受访者、大家庭、较少一起用餐的家庭以及有常客的家庭报告称，让家庭成员参与调查困难得多，非英语家庭和目前面临财务困难的家庭也是如此。在FoodAPS中，随着数据收集的进行，食物获取事件的无回应和报告不足情况往往会增加。对FoodAPS中可用辅助数据的分析揭示了这些误差，并为未来的食物获取调查提出了方法学上的改进建议。
