Hebert J R, Hurley T G, Hsieh J, Rogers E, Stoddard A M, Sorensen G, Nicolosi R J
Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, Worcester 01655.
Am J Epidemiol. 1994 Jul 15;140(2):132-47. doi: 10.1093/oxfordjournals.aje.a117224.
This study was conducted to assess the determinants of plasma concentrations of alpha-tocopherol, beta-carotene, retinol, and cholesterol fractions in a randomly selected subset of 203 workers participating in a worksite-based health intervention trial. Workers were from four companies in eastern and central Massachusetts, and all completed an 84-item semiquantitative food frequency questionnaire as part of baseline (preintervention) self-assessment instruments. At the time of fasting blood sampling, each participant also completed a short screening questionnaire for assessment of changes in dietary habits and tobacco exposure and for collection of data on use of vitamins and nutritional supplements. On the basis of the self-reported data, the authors found that they could explain 35% of the variability in plasma beta-carotene, 73% of the variability in alpha-tocopherol, 36% of the variability in retinol, and 19% of the variability in cholesterol. Plasma beta-carotene levels appeared to be affected by the use of supplements that did not contain carotene, indicating a beta-carotene sparing capability of other agents contained in these preparations. Plasma alpha-tocopherol levels were not similarly affected. These results compare favorably with those from studies that used more intensive dietary assessment techniques as the comparison criterion. Results are discussed in terms of implications for use of self-reported data in epidemiologic study analyses.
本研究旨在评估参与一项基于工作场所的健康干预试验的203名随机抽取工人的血浆中α-生育酚、β-胡萝卜素、视黄醇和胆固醇组分浓度的决定因素。这些工人来自马萨诸塞州东部和中部的四家公司，并且所有人都完成了一份84项的半定量食物频率问卷，作为基线（干预前）自我评估工具的一部分。在空腹采血时，每位参与者还完成了一份简短的筛查问卷，以评估饮食习惯和烟草暴露的变化，并收集有关维生素和营养补充剂使用的数据。根据自我报告的数据，作者发现他们可以解释血浆β-胡萝卜素变异性的35%、α-生育酚变异性的73%、视黄醇变异性的36%和胆固醇变异性的19%。血浆β-胡萝卜素水平似乎受到不含胡萝卜素的补充剂使用的影响，表明这些制剂中所含其他成分具有节省β-胡萝卜素的能力。血浆α-生育酚水平未受到类似影响。这些结果与使用更密集的饮食评估技术作为比较标准的研究结果相比具有优势。从在流行病学研究分析中使用自我报告数据的意义方面对结果进行了讨论。
