Collaboration across countries is a cornerstone of global health research and delivery. One Retinoblastoma World (1RBW) functions as an international consortium of treatment centers providing care to children diagnosed with retinoblastoma. This study sought to quantify collaborative linkages within 1RBW, characterize their scope and form, and examine perceptions of their role in improving retinoblastoma outcomes. A cross-sectional egocentric network study using mixed methods was undertaken. All registered treatment centers (n = 170) were invited to complete an online questionnaire documenting collaborative interactions between their own institution (ego) and partner organizations (alters). Network diagrams were constructed to illustrate relational patterns. Semi-structured interviews were conducted with key informants (n = 18) to contextualize and expand upon reported collaborations. Qualitative data were analyzed using an inductive thematic approach. A total of 56/170 (33%) treatment centers completed the survey. Respondents reported 112 distinct alters, comprising 80 treatment centers and 32 non-clinical organizations, yielding a network of 168 nodes. Collaboration most frequently involved referral pathways, expert consultations, and twinning or capacity-strengthening initiatives. Interview analysis revealed four dominant themes: definitions of partnership, motivations for collaboration, shared obstacles, and perceived advantages of collaborative engagement. While global cooperative efforts to reduce retinoblastoma mortality are well established, further integration of peripheral network members could strengthen overall connectivity.
