Volunteer Bias in Research on Friendship Among Emerging Adults

Five studies ( N = 5,150) relying on an exhaustive procedure addressed whether volunteer bias (VB) exists in friendship research among emerging adults (EAs). Consistently, the studies showed that women are more willing than men to participate in research on same-sex best friendship (SSBF). Studies 2 through 5 showed that friendship duration is not related to volunteering. Studies 3 and 4 showed that the friendships of volunteers were higher in positive friendship experiences compared to nonvolunteers. Finally, Study 5 showed that a significant portion of nonvolunteers ended up participating in research on SSBF. VB in research on friendship is an artifact that presents a concern for the generalizability and validity of findings relative to the friendship experiences of EAs. Recruitment strategies that could alleviate this problem are discussed.