Department of Counseling and Applied Educational Psychology, Bouvé College of Health Sciences, Northeastern University, Boston, MA;
Nicotine Tob Res. 2014 May;16 Suppl 2(Suppl 2):S144-50. doi: 10.1093/ntr/ntt109. Epub 2013 Aug 3.
Ecological momentary assessments (EMA) are increasingly used in studies of smoking behavior. Through EMA, examination of lagged relationships is particularly useful for establishing a temporal order of events and for identifying types and timing of risk factors. The time-varying effect model (TVEM) handles EMA data challenges and addresses unique questions about the time-varying effects.
Generalized TVEM was applied to EMA data from a smoking cessation study to investigate a "time-varying lagged" effect of negative affect on high smoking urges. Participants included 224 smokers with a smoking history of 23.1 years (SD = 9.8) smoking 27.3 cigarettes per day (SD = 10.7), which provided 11,394 EMAs following a quit attempt and prior to a smoking lapse.
The effect of negative affect was found to vary as a function of a time lag, with stronger immediate effects: estimated odds ratio (OR) of 2.7 for the lower nicotine-dependence group (time to first morning cigarette > 5 min, 57.6%) and OR of 2.4 for the higher nicotine-dependence group (≤ 5 min). The magnitude of the effect persisted up to 7 hr while decreasing over time.
This analysis confirmed the importance of negative affect as a precursor of smoking urges while showing that the magnitude of the effect varies over time. An assumption of a constant lagged effect may bias estimates of the relationships and fail to provide a comprehensive outlook of the relational dynamics.
生态瞬时评估（EMA）越来越多地用于吸烟行为的研究。通过 EMA，可以检查滞后关系，这对于确定事件的时间顺序和识别风险因素的类型和时间特别有用。时变效应模型（TVEM）处理 EMA 数据挑战，并解决关于时变效应的独特问题。
广义 TVEM 应用于戒烟研究中的 EMA 数据，以调查负面情绪对高吸烟冲动的“时变滞后”影响。参与者包括 224 名吸烟者，吸烟史为 23.1 年（SD=9.8），每天吸烟 27.3 支（SD=10.7），在戒烟尝试后和吸烟前提供了 11394 次 EMA。
发现负面情绪的影响随时间滞后而变化，即时效应更强：低尼古丁依赖组（第一次早上吸烟时间>5 分钟，57.6%）的估计比值比（OR）为 2.7，高尼古丁依赖组（≤5 分钟）的 OR 为 2.4。该效应的大小持续到 7 小时，同时随时间逐渐减弱。
该分析证实了负面情绪作为吸烟冲动的前兆的重要性，同时表明效应的大小随时间而变化。滞后效应的恒定假设可能会使关系的估计产生偏差，并不能全面了解关系动态。
