Collected Biannually since 1968, the Civil Rights Data Collection (CRDC) represents the U.S. Department of Education's most substantial effort to understand data related to students' educational opportunities throughout K-12 schooling, particularly for historically marginalized student populations. Due to the COVID-19 pandemic, the Department delayed planned data collection in the 2019-20 school year to the 2020-21 school year and released that data in November 2023. Center for Learner Equity (CLE) has produced a series of briefs that use CRDC data to understand the overall state of access and opportunity for students with disabilities in both traditional public and in charter schools. This report describes the methodological decisions necessary to produce the findings across the six briefs, particularly decisions made on variable use, data cleaning, and how to report findings.