Williams Geoffrey C, Hurley Thomas G, Thompson Frances E, Midthune Douglas, Yaroch Amy L, Resnicow Ken, Toobert Deborah J, Greene Geoffrey W, Peterson Karen, Nebeling Linda, Patrick Heather, Hardin James W, Hebert James R
Department of Medicine, Clinical and Social Sciences in Psychology, University of Rochester, Rochester, NY 14642, USA.
J Nutr. 2008 Jan;138(1):212S-217S. doi: 10.1093/jn/138.1.212S.
Measurement of percentage energy from fat is important in surveillance of populations and in epidemiologic studies examining relationships between diet and disease as well as for behavioral intervention studies seeking to change dietary behavior. The NCI percentage energy from fat screener (PFat) has adequately predicted percentage of energy from fat compared with 24-h recalls (24HR) in cross-sectional analyses. However, the instrument has not been evaluated for its ability to assess change of percentage energy from fat over time or in response to interventions to change dietary intake of fat. The objective of this analysis is to evaluate the performance of the PFat in assessing change in percentage energy intake from fat in a behavioral intervention setting. Four individual sites participating in the Behavior Change Consortium Nutrition Working Group administered both the PF at and multiple 24HR at baseline and follow-up to 278 participants. A measurement error model was used to assess agreement between the PFat and 24HR at baseline and follow-up. The PFat was consistent with 24HR in finding there was no significant change in percentage energy from fat as a result of the intervention. Both male and female participants in the intervention group demonstrated a significant increase in the correlation between PFat and 24HR from baseline to follow-up. Percentage energy from fat measured by PFat may be useful to provide estimates of change in mean intake of populations over time in longitudinal studies. Further methodologic research is called for in interventions producing significant changes and in diverse populations with adequate sample size.
测量脂肪供能百分比对于人群监测、研究饮食与疾病关系的流行病学研究以及旨在改变饮食行为的行为干预研究都很重要。在横断面分析中，美国国立癌症研究所的脂肪供能百分比筛查工具（PFat）与24小时回顾法（24HR）相比，能充分预测脂肪供能百分比。然而，该工具尚未评估其评估脂肪供能百分比随时间变化或对改变脂肪饮食摄入量干预措施的反应能力。本分析的目的是评估PFat在行为干预环境中评估脂肪供能百分比变化的性能。四个参与行为改变联盟营养工作组的独立研究点在基线和随访时对278名参与者同时使用了PFat和多次24HR。使用测量误差模型评估基线和随访时PFat与24HR之间的一致性。PFat与24HR一致，发现干预后脂肪供能百分比没有显著变化。干预组的男性和女性参与者从基线到随访时，PFat与24HR之间的相关性均显著增加。在纵向研究中，通过PFat测量的脂肪供能百分比可能有助于估计人群平均摄入量随时间的变化。对于产生显著变化的干预措施以及有足够样本量的不同人群，需要进行进一步的方法学研究。
