  Medical referrals between primary care physicians (PC) and specialist care
(SC) physicians profoundly impact patient care regarding quality, satisfaction,
and cost. This paper investigates the influence of professional networks among
medical doctors on referring patients from PC to SC. Using five-year
consultation data from a Portuguese private health provider, we conducted
exploratory data analysis and constructed both professional and referral
networks among physicians. We then apply Graph Neural Network (GNN) models to
learn latent representations of the referral network. Our analysis supports the
hypothesis that doctors' professional social connections can predict medical
referrals, potentially enhancing collaboration within organizations and
improving healthcare services. This research contributes to dissecting the
underlying mechanisms in primary-specialty referrals, thereby providing
valuable insights for enhancing patient care and effective healthcare
management.
