CONCLUSIONS
By combining family network data with data from a field experiment, we showed that network‐based financial incentive programmes for a behavioural health intervention might be more efficient than individual‐based programmes. While the field experiment was conducted in 2018, it is likely that our findings continue to apply in the current context since they are based on long‐standing social relationships among participants. Future HIV testing studies should assess interventions targeted at networks. More generally, public health studies should leverage data on participants’ social networks to generate new insights about population health and to spur on the development of new intervention approaches.