Plotnikoff Ronald C, Hotz Stephen B, Johnson Steven T, Hansen Janice S, Birkett Nicholas J, Leonard Lynne E, Flaman Laura M
School of Education, University of Newcastle, HPE Building, University Drive, Callaghan, NSW 2308 Australia.
J Am Diet Assoc. 2009 Aug;109(8):1392-7. doi: 10.1016/j.jada.2009.05.010.
Stages of change are related to dietary fat consumption. Few studies have examined stage occupation within the context of purchasing low-fat foods.
To determine the stage-prevalence of individuals for purchasing low-fat foods; identify the frequency of misclassification into action and maintenance (A/M) stages for purchasing for low-fat foods; and explain the demographic and cognitive-variable differences between pseudo (or false positive) A/M and true A/M individuals.
Data were collected using a self-administered questionnaire among English-speaking adults (n=1,001) who were randomly sampled by mail.
Descriptive statistics were used to compare the characteristics of the stage groups. Groups were compared using chi(2) tests and Student t test.
Of those who reported being in A/M stages, 32% were misclassified by the staging algorithm and were not true A/M low-fat food purchasers.
Individuals who are in A/M stages for buying low-fat foods still purchase high-fat foods. Stage misclassification may be a persistent problem in studies of dietary change using the Transtheoretical Model.
行为改变阶段与膳食脂肪摄入有关。很少有研究在购买低脂食品的背景下考察阶段归属情况。
确定购买低脂食品人群的阶段流行率；识别购买低脂食品时错分为行动和维持阶段的频率；并解释伪（或假阳性）行动/维持阶段人群与真正行动/维持阶段人群在人口统计学和认知变量方面的差异。
通过自填式问卷对通过邮件随机抽样选取的1001名讲英语的成年人收集数据。
采用描述性统计来比较各阶段组的特征。使用卡方检验和学生t检验对各群组进行比较。
在报告处于行动/维持阶段的人群中，32%被阶段划分算法错分，并非真正的购买低脂食品的行动/维持阶段人群。
处于购买低脂食品行动/维持阶段的个体仍会购买高脂食品。在使用跨理论模型进行的饮食变化研究中，阶段错分可能是一个持续存在的问题。
