Quantifying multidisciplinary collaboration in Huntington’s disease before and after service redesign: a social network analysis

Effective multidisciplinary collaboration underpins integrated care for people living with Huntington’s disease (HD). Traditional evaluations focus on patient outcomes or self-reported collaboration, which may not capture the underlying structure of team interactions. Social network analysis (SNA) provides an objective method to map collaboration structures and quantify changes associated with service redesign. This study aimed to evaluate structural changes in multidisciplinary team collaboration following service redesign in a specialist HD clinic using encounter-derived SNA. We conducted a retrospective before–after cohort study comparing pre-redesign (2014–2015, Before ) and post-redesign (2018–2019, After ) periods, including all clinic attendees. Provider participation was extracted from electronic health records and aggregated at the patient-day level. Co-occurrence networks were constructed using Pearson correlation coefficients of provider co-occurrence patterns across shared patient-days, generating weighted undirected networks of disciplinary collaboration. Network metrics, including community structure, modularity ( Q , a measure of network division into communities), and local (degree, betweenness) and global (PageRank) centrality measures were used to characterise network structure. Secondary analyses examined patient-level outcomes, including survival, functional decline, non-elective hospital admissions, non-elective residential care placement, emergency services and specialist palliative care involvement, and advance care plan completion. A total of 685 patients contributed 9797 encounters (3926 Before ; 5871 After ). Co-occurrence patterns shifted from more concentrated dyadic co-participation toward more interconnected allied health involvement across patient-days. Network communities decreased from nine ( Q = 0.603) to seven ( Q = 0.262), reflecting reduced fragmentation and increased cross-disciplinary integration. Allied health providers showed the largest increases in degree centrality, while PageRank changes were heterogeneous across disciplines. The neurologist remained structurally central across both periods, while the clinical liaison showed reduced relative centrality. Overall, the network demonstrated increased multidisciplinary integration with sustained medical centrality. Short-term patient outcomes were largely unchanged. Service redesign in a specialist HD clinic was associated with reduced network fragmentation and reorganisation of multidisciplinary collaboration, particularly among allied health providers, alongside minimal short-term changes in patient outcomes. Encounter-derived SNA provides an objective method to assess structural changes in team collaboration, complementing traditional outcome measures and supporting evaluation of multidisciplinary care processes in complex chronic healthcare settings.