Race/ethnicity: who is counting what?

Abstract--Misclassification of race and ethnicity in administrative data may produce misleading results if it is overlooked or ignored. In this study, we examined the racial/ethnic classifications of 1,084 veterans with stroke in Florida who received inpatient and outpatient services within the Department of Veterans Affairs (VA) healthcare system and who were also eligible for Medicare between 2000 and 2001. We compared the reliability of racial/ethnic classifications between VA inpatient data, VA outpatient data, and Medicare data. Our results showed that (1) the rate of unknown racial/ethnic classification in VA outpatient and inpatient data was high, (2) minimizing the unknowns by substituting known values from other data when available would greatly enhance the overall and individual classification reliability, (3) black and white classifications in the VA data had stronger agreement with Medicare data, and (4) Medicare data may under-represent Hispanic patients. Key words: administrative data, ethnicity, Department of Veterans Affairs, Medicare, race, racial/ethnic classification, reliability, Social Security Administration, stroke, validity, veterans. INTRODUCTION Stroke is one of the leading causes of death and major cause of serious and long-term disability in the United States population [1] as well as in the veteran population [2-3]. Numerous studies have shown racial/ ethnic disparities in stroke. In a recent study using a continuous annual household-based survey of the United States population from 1999 to 2001, McGruder et al. reported that racial/ethnic disparities existed in stroke prevalence, risk behaviors, and medical history [4]. In a recent selective review of literature published between 1991 and 2003, Stansbury et al. provided a broad perspective on race/ethnicity across the continuum of stroke care [5]. Their review confirmed the increased stroke incidence and mortality among black Americans and demonstrated the higher prevalence of hypertension among black and Hispanic patients and atrial fibrillation among non-Hispanic white stroke patients. Within the Department of Veterans Affairs (VA) healthcare system, Jones et al. examined racial variation and initial stroke severity among 982 veteran patients who received acute stroke care [6]. Using the Canadian Neurological Scale, Jones et al. showed that unadjusted scores were significantly lower for black patients than for white patients (7.96 vs 9.32, p = 0.04), which indicated greater stroke severity among black patients. Reports on racial/ethnic disparities in the use of stroke-related procedures and services showed mixed results. In an earlier study among a national sample of veterans with ischemic stroke, Oddone et al. reported that the likelihood of angiography for black patients was 47 percent that of white patients and Hispanic patients were only 75 percent as likely as non-Hispanic white patients to receive the procedure [7]. On the contrary, Goldstein et al. found no significant differences between white and nonwhite patients in the use of a variety of stroke-related procedures and services among 1,073 veterans diagnosed with acute ischemic stroke [8]. In two separate studies on racial/ethnic disparities in poststroke rehabilitation outcomes, Horner et al. showed that black veteran patients had greater residual physical deficits from stroke than white patients [9] and that low-income black veteran patients experienced poorer functional recovery over a 12-month period [10]. Most of these studies were based on data extracted from the VA inpatient and/or outpatient databases. Less, however, is known about the agreement of racial/ethnic classification for stroke patients between the VA inpatient and outpatient databases and Medicare data. Although the overall veteran population has been declining, VA healthcare enrollees have been increasing. The number of veteran patients age 65 and over is projected to increase rapidly in the next 10 years. …