BACKGROUND: The Pediatric Epilepsy Research Consortium (PERC) Health Equity Special Interest Group (SIG) used Concept Mapping to begin developing Common Data Elements (CDE) about social determinants of health to standardize data collection and facilitate robust evaluation of health disparities in pediatric epilepsy research. METHODS: Concept Mapping is a structured participatory mixed method suited for developing group consensus. PERC members (1) identified social factors that are important to measure in pediatric epilepsy research, (2) sorted factors into meaningful categories, and (3) rated the factors on importance and ease of measurement. The authors applied multidimensional scaling to the sorting data, created spatial point maps, and used hierarchical cluster analysis to define concepts. A bivariate scatterplot was used to explore importance versus ease of measurement to prioritize factors for inclusion. The PERC Health Equity SIG met on three occasions to interpret research findings and finalize a CDE set. RESULTS: Eighty-one PERC members generated 110 candidate factors. Thirty PERC members completed sorting, and 48 completed rating. The factors grouped into a five-cluster solution: "Household and Neighborhood Resources," "Family Context," "Individual Demographics," "Healthcare Experiences," and "School." Sixty-two items were rated with high importance, of which 34 were rated with high ease. The PERC Health Equity SIG decided by consensus to include most items with high importance and high ease ratings, plus selected additional items. The final CDE set consists of 42 items. CONCLUSIONS: Inclusion of CDE in future pediatric epilepsy research will enable researchers to undertake systematic analyses of health disparities.