Another important finding relates to the role of gender in the spread of alcohol consumption behavior. Our findings suggest that female contacts are significantly more likely to influence the spread of heavy alcohol consumption behavior than male contacts. While differences may have been expected in principals of different genders (i.e. men and women perceiving peer influences and social norms about alcohol differently (36,37)), the effect of contact gender was unexpected. One possible explanation for these effects is that significant increases in drinking behavior among women are much less common and more often associated with dramatic shifts in roles and contexts in life, such as job changes and work stress, thus reflecting an impact of confounding factors (38). A related possibility is that changes in perceived norms towards drinking among women are more powerfully transmitted along social networks, possibly due to women usually being perceived as sharing norms for less alcohol consumption (37, 38). That is, a woman changing her behavior is a stronger stimulus.
