Nicola Jones, ‘Happiness spreads but depression doesn’t’, http://www2.warwick.ac.uk/newsandevents/pressreleases/happiness_spreads_but/, University of Warwick (bezocht: 31 augustus 2015).

Reduce depression

Results offer implications for improving adolescent mood. In particular they suggest the hypothesis that encouraging friendship networks between adolescents could reduce both the incidence and prevalence of depression among teenagers. (…) Promotion of any friendship between adolescents can reduce depression since having depressed friends does not put them at risk, but having healthy friends is both protective and curative.

DOI

DOI: 10.1098/rspb.2015.1180