A Randomized Placebo-Controlled Study on the Effectiveness of the "Three Good Things for Others" Intervention.

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 2 weeks, follow-up after 4 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).