Case Ascertainment of Sickle Cell Disease Using Surveillance or Single Administrative Database Case Definitions

In the absence of access to surveillance system data, single-source administrative databases are often used to study health care utilization and health outcomes among people with sickle cell disease (SCD). We compared the case definitions from single-source administrative databases with a surveillance case definition to identify people with SCD.

We used data from Sickle Cell Data Collection programs in California and Georgia (2016-2018). The surveillance case definition for SCD developed for the Sickle Cell Data Collection programs uses multiple databases, including newborn screening, discharge databases, state Medicaid programs, vital records, and clinic data. Case definitions for SCD in single-source administrative databases varied by database (Medicaid and discharge) and years of data (1, 2, and 3 years). We calculated the proportion of people meeting the surveillance case definition for SCD that was captured by each single administrative database case definition for SCD, by birth cohort, sex, and Medicaid enrollment.

In California, 7117 people met the surveillance case definition of SCD from 2016 through 2018; 48% of this group was captured by the Medicaid case definition and 41% by the discharge case definition. In Georgia, 10 448 people met the surveillance case definition of SCD from 2016 through 2018; 45% of this group was captured by the Medicaid case definition and 51% by the discharge case definition. These proportions differed by years of data, birth cohort, and length of Medicaid enrollment.

The surveillance case definition identified twice as many people with SCD as the single-source administrative database definitions during the same period, but trade-offs exist in using single administrative databases for decisions on policy and program expansion for SCD.