Many sexual and reproductive health studies rely on individual level measures, especially those concerned with behavioural outcomes. However, it has been demonstrated in other fields of health research that area level factors matter, above and beyond individual level measures (see for example studies 17–20 cited by Smith and Subramanian¹). The need to simultaneously consider factors at individual and partnership levels, as well as sexual networks and variations across subpopulations to better understand STI/HIV epidemiology has recently been emphasised.² The study by Smith and Subramanian thus provides important evidence in …