Buzzard I M, Faucett C L, Jeffery R W, McBane L, McGovern P, Baxter J S, Shapiro A C, Blackburn G L, Chlebowski R T, Elashoff R M, Wynder E L
Department of Preventive Medicine and Community Health, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298, USA.
J Am Diet Assoc. 1996 Jun;96(6):574-9. doi: 10.1016/S0002-8223(96)00158-7.
The purpose of the study was to evaluate two methods of dietary assessment for monitoring change in fat intake in a low-fat diet intervention study.
The two dietary assessment methods were a 4-day food record (4DFR) and an unannounced 24-hour dietary recall conducted by telephone interview (referred to as a telephone recall [TR]). Subjects were assigned randomly to either a low-fat diet intervention group or a control group that received no counseling about fat intake. Dietary data were collected at baseline, 6 months, and 12 months.
Two hundred ninety postmenopausal women with localized breast cancer were recruited at seven clinical centers in the United States.
Analysis of variance was used to test for significant differences in mean fat and energy intakes.
Three sources of error were identified: (a) an instrument effect, suggesting underreporting at baseline of approximately 8% in mean energy intake and 11% in mean fat intake in the TR group compared with the 4DFR group (P = .0001); (b) a repeated measures effect observed for the 4DFR, suggesting underreporting of approximately 7% for energy intake and 14% for fat intake in the control group at 6 and 12 months compared with baseline values (P < .001); and (c) an adherence effect (or compliance bias), suggesting greater compliance to the low-fat intervention diet when subjects were keeping food records than when estimates were based on the unannounced TR. Compared with the TR, the 4DFR overestimated the extent of fat reduction in the low-fat diet intervention group by 41% (P = .08) and 25% (P = .62) at 6 and 12 months, respectively.
Multiple days of unannounced 24-hour recalls may be preferable to multiple-day food records for monitoring dietary change in diet intervention studies.
本研究旨在评估在一项低脂饮食干预研究中，两种膳食评估方法监测脂肪摄入量变化的情况。
两种膳食评估方法分别为4天食物记录（4DFR）和通过电话访谈进行的不预先通知的24小时膳食回顾（称为电话回顾[TR]）。受试者被随机分配到低脂饮食干预组或未接受脂肪摄入咨询的对照组。在基线、6个月和12个月时收集膳食数据。
在美国七个临床中心招募了290名患有局部乳腺癌的绝经后妇女。
采用方差分析来检验平均脂肪和能量摄入量的显著差异。
确定了三个误差来源：（a）仪器效应，表明与4DFR组相比，TR组在基线时平均能量摄入量低报约8%，平均脂肪摄入量低报11%（P = .0001）；（b）4DFR观察到的重复测量效应，表明对照组在6个月和12个月时与基线值相比，能量摄入量低报约7%，脂肪摄入量低报14%（P < .001）；（c）依从效应（或依从性偏差），表明受试者记录食物时比基于不预先通知的TR进行估计时，对低脂干预饮食的依从性更高。与TR相比，4DFR在6个月和12个月时分别高估了低脂饮食干预组脂肪减少程度的4l%（P = .08）和25%（P = .62）。
在饮食干预研究中监测饮食变化时，多日不预先通知的24小时回顾可能比多日食物记录更可取。
