Most studies on social ties and health use individual-level data, as surveys typically collect information from one member per household. However, social ties, by definition, involve more than one person. Studies that include dyads show that individuals in the same relationship often experience and report on their relationship in quite different ways (Proulx and Helms 2008). Independent reports, as well as discrepancies between reports, may be linked to health outcomes. We should take advantage of existing longitudinal data sets that include more than one focal individual. New data collection efforts should go beyond the individual to include data from a range of linked social ties. As recent work shows, including reports from several network members may reveal important relationship/health linkages that go beyond one individual (Smith and Christakis 2008).
