Investigating the impact of using an alternate classification method for race and Hispanic ethnicity on rates of reported gonorrhea.

Background We aimed to examine how the classification of gonorrhea cases by race and Hispanic ethnicity (HE) affects the measurement of racial/HE disparities in the rates of reported gonorrhea. Methods We examined gonorrhea cases reported through the National Notifiable Diseases Surveillance System from January 1, 2010, to December 31, 2017, and assigned race and HE using (1) "current classification," where cases with HE are classified as Hispanic regardless of race (e.g., Hispanic, non-Hispanic White, and non-Hispanic Black), and 2) "alternate classification," which separates each race category by HE (e.g., Hispanic White and non-Hispanic White). We estimated annual gonorrhea rates during 2010 to 2017 by race/HE category and calculated disparity measures (index of disparity, population-attributable proportion, and Gini coefficient) for gonorrhea rates under each classification strategy. Results All disparity measures revealed decreases in racial/HE disparities in the rates of reported gonorrhea during 2010 to 2017, regardless of classification strategy; however, the magnitude of the disparity and the percent change in the disparity over time varied across disparity measures. Conclusions Understanding how classification of race/HE affects observed disparities is critical when monitoring interventions to reduce disparities and improve health equity.