The aim of our study was to test the effectiveness of the “three good things for others” intervention. We used the randomized controlled trial method, with four measurements (pretest, posttest, follow-up after two weeks, follow-up after four weeks) and with random assignment of participants to experimental and placebo control groups. We investigated the effects of the intervention on prosocial behavior, and in addition on positive and negative affect, and positive orientation (a general tendency to approach reality in a positive way). The results showed an increase in positive affect and a decrease in negative affect in the experimental group a day after the intervention. These effects, however, did not endure over the next two or four weeks. We also observed a statistically significant increase in prosocial behavior in the placebo control group, in which participants engaged in a task of recalling childhood memories. The results are discussed and recommendations for future studies are proposed.

中文翻译：

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一项关于“对他人有益的三项干预措施”有效性的随机安慰剂对照研究

我们研究的目的是检验“对他人有益的三件事”干预的有效性。我们使用了随机对照试验方法，进行了四项测量（前测，后测，两周后随访，四周后随访），并将参与者随机分配到实验组和安慰剂对照组。我们调查了干预对亲社会行为的影响，以及对正面和负面影响以及正面倾向（以积极方式接近现实的总体趋势）的影响。结果表明，干预后一天，实验组的积极影响增加而消极影响减少。但是，这些影响在接下来的两到四周内不会持续。我们还观察到安慰剂对照组的亲社会行为有统计学上的显着增加，参与者从事回忆童年记忆的任务。讨论了结果，并提出了进一步研究的建议。