Sex Transm Dis

Background:The association between county-level social capital indices (SCIs) and the three most commonly reported sexually transmitted infections (STIs) in the United States is lacking. In this study, we determined and examined the association between two recently developed county-level SCIs (i.e., Penn State social capital index [PSSCI] vs. United States Congress social capital index [USCSCI]) and the three most commonly reported bacterial STIs (chlamydia, gonorrhea and syphilis) using spatial and non-spatial regression techniques.Methods:We assembled and analyzed multi-year (2012\u20132016) cross-sectional data on STIs and two SCIs (PSSCI vs. USCSCI) on counties in all 48 contiguous states. We explored two non-spatial regression models (univariate and multiple generalized linear models) and three spatial regression models (spatial lag model, spatial error model and the spatial autoregressive moving average model) for comparison.Results:Without exception, all the SCIs were negatively associated with all three STI morbidity. A one-unit increase in the SCIs were associated with at least 9% (p