To examine whether the association between green space and post-stroke mortality varied according to major roadway proximity, a cross-product term between quartiles of NDVI and the natural logarithm of residential proximity to a major roadway was included in the model. We also used cross-product terms to test whether the associations with green space differed by factors related to biological susceptibility (age475, diabetes, sex) and socioeconomic indicators of vulnerability (median household income in the lowest quartile and percent of adults aged Z25 years without a high school diploma in the highest tertile) individually in separate models.