• Many interventions include multiple components (e.g., education + peer support + network mapping) and isolating the unique contribution of the network component remains challenging.
• Measures of social networks (structure, position, density, cohesion) are often absent or simplistic, limiting insight into how network change mediates outcomes.
• Intervention‐engagement and retention pose a considerable challenge, especially in digital or adolescent contexts.
• Heterogeneity in effect sizes, populations, behaviours, and follow-up durations means that generalisability is challenging and still emergent rather than established.
• There is a growing need to design interventions with network theory built in (rather than retrofitting network concepts), to test causal mechanisms (who influences whom, how ties change, what the ripple/diffusion effects are) and to integrate network and behaviour change measurement.
• Across chronic disease settings, the evidence on network/support interventions remains weak or very low certainty highlighting the need for more high‐quality RCTs in those domains.