  Purpose: The purpose of this paper is to identify the factors influencing the
growth of healthcare virtual communities of practice (VCoPs) through a
seven-year longitudinal study conducted using metrics from social-network and
semantic analysis. By studying online communication along the three dimensions
of social interactions (connectivity, interactivity and language use), the
authors aim to provide VCoP managers with valuable insights to improve the
success of their communities. Design/methodology/approach: Communications over
a period of seven years (April 2008 to April 2015) and between 14,000 members
of 16 different healthcare VCoPs coexisting on the same web platform were
analysed. Multilevel regression models were used to reveal the main
determinants of community growth over time. Independent variables were derived
from social network and semantic analysis measures. Findings: Results show that
structural and content-based variables predict the growth of the community.
Progressively, more people will join a community if its structure is more
centralised, leaders are more dynamic (they rotate more) and the language used
in the posts is less complex. Research limitations/implications: The available
data set included one Web platform and a limited number of control variables.
To consolidate the findings of the present study, the experiment should be
replicated on other healthcare VCoPs. Originality/value: The study provides
useful recommendations for setting up and nurturing the growth of professional
communities, considering, at the same time, the interaction patterns among the
community members, the dynamic evolution of these interactions and the use of
language. New analytical tools are presented, together with the use of
innovative interaction metrics, that can significantly influence community
growth, such as rotating leadership.
