When a Doctor Knows, It Shows: An Empirical Analysis of Doctors' Responses in a Q&A Forum of an Online Healthcare Portal

Question-and-answer (Q&A) forums are gaining popularity as a user-engagement tool to drive traffic on multiservice portals. In a platform market model, demand-side users seek answers from supply-side users because such answers can indicate value offered, reduce buyer uncertainty, and offer social proof. Analyzing user-generated content on the Q&A forum of a prominent healthcare portal, we find that the introduction of doctors' responses has a significant causal impact on demand-side user perception of medical services offered. More importantly, our research suggests that doctors' specialty, experience, qualifications, transparency in appointment booking, service fees, and response quality moderate the effect of doctors' Q&A responses on user recommendations. These results demonstrate that because of information asymmetry in healthcare, doctors use thoughtful online responses not only to socially interact with patients but also to signal their expertise.