Oxytocin, empathy, altruism and charitable giving : experimental evidence from blood donations

We conducted a field experiment in the natural setting of blood donations to test how oxytocin relates to empathy and altruism. We randomly assigned blood donors in the Croatian Institute for Transfusion Medicine to three groups with the aim to induce different levels of empathy by showing a neutral video to the donors from the control group and an emotional to the donors from the first and second treatment groups. In addition to watching the emotional video, donors from the second treatment group are given a gift which relates to the emotional story from the video. We find no effect of our treatment on induced levels of oxytocin. Null effects of our treatments could be explained by the above average baseline levels of oxytocin and inability of our treatments to provoke emotional stimuli in blood donors. Nonetheless, for our empathy measures we find the effect of gift exchange on empathic concerns, but not on perspective taking. After our experimental treatments, we followed the return of our blood donors for a whole year. We find that only variable which consistently predicts return for blood donation in stated period is the number of previous donations. From policy perspective it is an important finding. Especially for hospitals and other blood providers when faced with time and resource constraints.