Topic Hijacking in Online Health Communities

Online health communities (OHCs) are conventionally recognized as information commons for mutual exchange among peer users with similar health concerns. Extant research reckons that engagement patterns universally conform to implicit norms guided by social exchange; that is, when a topic owner (i.e., user who initiates a topic thread) receives replies from peer users, they are said to acquire social support. This overlooks topic hijacking, a prevalent phenomenon where peer users solicit instead of providing support to topic owners. Drawing on the territoriality theory, we conceptualize that OHCs, as a form of health information commons, accommodate the emergence of personal territories when a user initiates a topic for support seeking. We posit topic hijacking as territorial infringement, and theorize a fight–flight–flex response framework for topic owners who experience topic hijacking, as well as the contingency of hijacking competitiveness on responses. Using data from 368 topics in an OHC, we develop measures of hijacking and hijacking competitiveness (competitive vs. complementary). Regression analyses attest to our research hypotheses that hijacking triggers (i) defensive responses at both the topic owner territory and community levels, including fight (marking self-presence) and flight (disengagement), and (ii) expansive response at the community level manifested by flex (subsequent hijacking of other topic owners’ territories). Moreover, competitive hijacking intensifies defensive responses, while complementary hijacking fosters territorial expansion. This study advances the OHC literature by recognizing topic hijacking as territorial infringements disrupting topic owner engagement, introducing a novel fight–flight–flex framework that captures both defensive and expansive responses, and identifying hijacking competitiveness as a boundary condition discerning defensive versus expansive responses to hijacking. Our findings offer implications for platform governance by showing how different hijacking forms may disrupt or enhance community vitality.