Department of Psychology, University of Sheffield, Sheffield, UK.
Psychol Health. 2010 Mar;25(3):365-81. doi: 10.1080/08870440802642148.
The present study tests the efficacy of a single implementation intention to increase intake over a 6-month period, and investigates whether deploying a second implementation intention at 3 months can sustain the long-term impact, compared with passive and active control groups. Participants (N = 650) completed single-item and FFQ measures of behaviour and motivation at baseline before being randomised to one of six conditions in a between-persons design. Intention to treat analysis revealed that for the single-item measure: (1) a single implementation intention is an effective means of initiating fruit and vegetable increase over a 3-month period, but this effect is not sustained over 6 months; (2) administering a second implementation intention at 3 months was successful in increasing intake over 6 months, and acted as a booster on the initial impact; and (3) neither the passive nor active control condition had any impact on behaviour. However, no effects of the manipulations on fruit and vegetable intake were found when behaviour was assessed by the FFQ measure. Secondary analyses showed that reported increases in intake were not related to demand characteristics. The findings are discussed in relation to their conceptual and practical value.
本研究旨在测试单一实施意向在 6 个月内增加摄入量的效果，并调查与被动和主动对照组相比，在 3 个月时部署第二个实施意向是否可以维持长期影响。在被随机分配到 6 种条件之一的个体间设计之前，参与者（N=650）在基线完成了行为和动机的单项和 FFQ 测量。意向治疗分析表明，对于单项测量：（1）单一实施意向是在 3 个月内启动水果和蔬菜增加的有效手段，但这种效果在 6 个月内无法维持；（2）在 3 个月时实施第二个实施意向成功增加了 6 个月的摄入量，并对初始影响起到了促进作用；（3）被动和主动对照组都对行为没有任何影响。然而，当通过 FFQ 测量评估行为时，没有发现这些操作对水果和蔬菜摄入量的影响。二次分析表明，报告的摄入量增加与需求特征无关。研究结果在概念和实践价值方面进行了讨论。
