MONDAY, July 21, 2025 (HealthDay News) -- Race definitions have limited impact on cancer rates for Whites, Blacks, and Asians, but do impact rates in multiracial individuals, according to a study published online July 21 in Cancer.Mandi Yu, Ph.D., from the National Cancer Institute in Bethesda, Maryland, and colleagues obtained cancer incidence rates from the National Cancer Institute Surveillance, Epidemiology, and End Results Program and cancer deaths from the National Vital Statistics System. Rate ratios were used to compare age-standardized rates of incidence and mortality in 2020 across three definitions: two definitions compliant with the 1997 Office of Management and Budget (OMB) standards (race-alone and race-alone-or-in-combination) and one compliant with the previous 1977 OMB standard (bridged-race).The researchers found that compared with the population data, the proportions of multiracial individuals were lower in the incidence and death data, with the degree varying by age, race, and geography. For Whites, Blacks, and Asians, race definitions had minimal impact on rates. For Native Hawaiians or other Pacific Islanders (NHOPIs), race-alone-or-in-combination rates were lower compared with race-alone rates, indicating an underrepresentation of multiracial NHOPI individuals in incidence data. For American Indians/Alaskan Natives (AI/ANs), race-alone and race-alone-or-in-combination yielded similar rates, but they were significantly lower than their bridged-rate counterparts, indicating a mismatch in classification of AI/AN between incidence and population data."Enhancing the accuracy of patients' self-reported racial identification and incorporating multiracial classifications into hospital data collection systems are essential steps for improving the comparability between cancer incidence and census-based population data," Yu said in a statement.Abstract/Full Text.Sign up for our weekly HealthDay newsletter