Our objective was to conduct a review of literature on social determinants of health (SDoH) in clinical data in order to characterize data quality (DQ) issues specific to this area of research. To reach this objective, we conducted a realist review - a theory-driven, deductive, and systematic literature review. This research is unique because it brings together information about a variety of social determinants variables in order to examine the issues inherent to social informatics as a field of study. It is the first to summarize how specific issues of bias and validity are introduced into social determinants research, and to gather information about how the process of linking datasets has the potential to introduce data quality issues into research that relies on integrated datasets.