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Studying Vulnerable Populations: Lessons From the Roma Minority

Kósa, Karolina*; Ádány, Róza

doi: 10.1097/01.ede.0000258919.15281.4f

There are important disparities in health outcomes between racial/ethnic minorities and majorities in all countries where minority health has been investigated. This holds true for the largest minority population of Europe, the Roma, although research data related to Roma are scarcer and more contested than for other minorities. We discuss major obstacles that hinder or prevent the collection of reliable data in Roma and other minorities. The definitions and classification systems on race/ethnicity vary widely, pointing to the social construction of both race and ethnicity. Imprecision in taxonomy and definition of target groups is compounded by challenges in data collection, analysis, and interpretation, along with ethnocentricity that shapes the perspectives and approaches of the researchers. However, administrative data collection on race/ethnicity serves legitimate purposes although such data must comply with less-stringent quality requirements as opposed to data meant for scientific analysis. Research on minorities should consider race/ethnicity as proxy indicators of complex health determinants, and should aim at dissecting these determinants into separate items. Careful documentation of methodology and active involvement of the minorities themselves can increase trust between the investigators and the research subjects, which can in turn improve research on minority health.

Supplemental Digital Content is Available in the Text.

From the *Division of Health Promotion and †Department of Preventive Medicine, Faculty of Public Health, University of Debrecen, Hungary.

Editors’ Note:Epidemiology and Society provides a broad forum for epidemiologic perspectives on health research, public policy, and global health.

Submitted 21 July 2006; accepted 4 December 2006.

Supported by grants ISZKF-206/2004 of the Ministry of Environmental Protection; ETT 445/2003 of the Ministry of Health, Social and Family Affairs; and NKFP-1B/0013/2002 of the Ministry of Education, Hungary.

Supplemental material for this article is available with the online version of the journal at; click on “Article Plus.”

Correspondence: Karolina Kósa, Division of Health Promotion, Department of Preventive Medicine, Faculty of Public Health, University of Debrecen, POB 2., Debrecen 4012, Hungary. E-mail:

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Health inequalities (or health disparities)1,2 constitute a major focus of attention for both epidemiologic research and health policy. The number of English-language papers in PubMed under the medical subject headings of “socioeconomic factors” and “health” increased from 1279 in 1968–1980 to 9352 in 1993–2005.3 The documentation of strong associations between health and economic development has in turn led to increased interest in health inequalities among policy makers.4

Research into health inequalities according to race and ethnicity has shown consistent disadvantages in health status, morbidity, and mortality for various racial/ethnic groups in minority positions.5–8 The causes of inequalities between blacks and whites in the United States and among a range of ethnic groups in the United Kingdom have been attributed in varying degree to racism and to cultural and socioeconomic differences.9–12 The extent and determinants of health inequalities in other minorities (particularly those among the Roma minority in Europe) have been less extensively investigated.

Roma people (also known as Gypsy, Sinti, or Tzigane) constitute Europe's largest minority. Their number is estimated between 6.3 and 8.5 million people,13 roughly the population of Sweden or Austria. Roma migrated in several waves from northern India, their presence in Europe being documented as early as the 12th century.14 They have been among the poorest people in Europe, and the collapse of socialist regimes around 1990 in central and eastern European countries—where the largest populations of Roma live—has had an especially harsh impact, worsening their already unfavorable living conditions and health.15

Literature reviews have documented unfavorable health status, lower life expectancy, and greater communicable disease burden for Roma compared with non-Roma in the Czech and Slovak Republics,16 Spain,17 and Hungary.18,19 Roma have higher infant mortality rates,20 with higher rates of low birth weight, preterm birth, and intrauterine growth retardation.21 Average blood lead levels in Spain were found to be substantially higher in Gypsy compared with white children.22 Access to health care and provision of services for Roma in several countries has been burdened by limited coverage and discrimination.23

Several factors have contributed to heightened interest in the welfare of Roma in Europe24,25 including increasing marginalization of Roma (in both economic and social terms),26 higher birth rates compared with majority populations, and increased mobility within the European Union. This has led to the launch, in 2005, of a large-scale initiative, “The Decade of Roma Inclusion,” involving 8 national governments and several international organizations, including World Bank, United Nations Development Program, Open Society Institute, and European Roma Rights Center.27

Despite the vulnerability of Roma and increased political interest in their welfare, there remains a dearth of research data on their health status.17,20,24,28,29 This work presents an overview of issues that hamper the collection of reliable health data for Roma and other minorities.

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Who Are The Subjects?

Definition, Taxonomy, and Data Collection on Ethnicity

“Ethnic” groups are people classed according to common racial, national, tribal, religious, linguistic, or cultural background.30,31 In this context, “minority” people are “part of a population differing from others in some characteristics and often subjected to differential treatment.”30 Collection of data on ethnicity and race has been a controversial issue. Such data are laden with historical examples of abuse, and contemporary examples of misuse. For example, crime statistics reported on an ethnic basic can reinforce prejudice.11,32 However, controversy around such data is not due simply to their potential for abuse but also to legitimate questions as to what race/ethnicity is, and how people should be classified. As demonstrated by Table 1, there is no theoretical grounding and no standard classification of racial/ethnic/minority groups. The taxonomy is always context-dependent and subject to change with context.33–41







Designation of the same people can change from one country to another, making identification or comparison difficult. The following names have been used to identify Roma people: Sinti/Zigeuner (in Germany), Tsigan (Bulgaria, Romania), Zingari (Italy), Cigány (Hungary), Gitano (Spain), Manoush/Bohemian (France), Tinker/Tinkler (United Kingdom), and Kalderash (worldwide).42 The US National Library of Medicine offers the term “Gypsies” as a medical subject heading in its PubMed database.3 Health research projects have included Roma in the heterogeneous group of Travelers in the United Kingdom and Ireland, although Travelers, having similar traditions, are ethnically distinct from Roma.43,44 These people themselves prefer to be called Roma, the name adopted in 1971 by the first World Romani Congress to denote them as a nation.42

The changing designation of minorities has usually been linked to changes in official (government) recognition, which makes the trend-analysis of minority data, even within the same population, challenging. For example, “Roma” was not among the options for ethnic identity in the census of 1980 in Hungary, although it was an option in censuses before and after that year (ethnicity itself was not an item in the census of 1970).45 Asian Indians were counted as “Hindus” in US censuses from 1920 to 1940, as “white” from 1950 to 1970, and as “Asians or Pacific Islanders” in 1980 and 1990.46

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Self-Reporting of Minority Status

Racial/ethnic classifications offer socially constructed categories that minorities can choose from to identify themselves. One question that arises is whether ethnic or racial groups wish to report themselves as minorities at all. Roma people and their representatives have been divided on this question. Some regard such reporting as necessary for developing sound minority policy, while others are opposed to any data collection by ethnicity on the grounds of past and present misuse of such data.47 Indeed, there has been a long-recognized practice among Roma people not to identify themselves as ethnic minorities in census or official data collection exercises. This has resulted in their chronic underenumeration.13,20,47–49 For this reason, even those countries in which data on ethnicity are collected must resort to estimation when counting Roma.

Reliable population numbers are important in defining sampling frames for research studies, as well as for calculating health indices such as disease rates. Estimates of the total number of Roma people in European countries can vary up to 50%,13,50 which understandably complicates assessment of their health and health needs.

The underestimation that can occur with self-identification of racial/ethnic status was recognized early on in sociological research. An alternative is ethnic/racial identification by an observer. Three constructs for minority status have been described.51 There is internal racial/ethnic identity (the individual's belief), which might or might not be the same as expressed identity (conveyed by speech and deed). These 2 are related but not necessarily the same as external identity (an observer's belief about an individual).51

The problem of underreporting of minority identity is compounded by the fact that self-perception (and self–reporting) of race/ethnicity is fluid. It can shift with age and with changes over time in societal attitudes towards race relations and multiculturality (described in various ethnic groups).20,52–54 Self-reported ethnic identity might even be influenced by the order of relevant questions asked.55

One consequence of this fluidity of minority identity is that “population growth” or “decline” of minorities can occur without changes in birth rates or immigration trends. The number of self-identified Roma in Hungary increased 29-fold between the censuses of 1980 and 2001,56 while the [Native] Indian population in the United States increased 6-fold between 1960 and 1990.57 Such large changes presumably represent major shifts in self-identification.

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Observer Reporting of Minority Status

Compared with self-identification, observer identification has consistently been found to estimate higher numbers of Roma.20 An observer-based estimate by the Slovak state administration in 1989 found 3.2 times more Roma than was reported in the 1991 census based on self-identification.58 Results were similar in Hungary, comparing observer identification of Roma people in a 2003 nationally representative research sample with self-report in the 2001 census.59

However, observer classification of race/ethnicity has its own subjectivity. Observer classifications of race for US infants who die within a year of birth often differ on birth and death certificates for the same baby. Differential racial classification in such cases has been found to be more than 31 times as likely with different-race than with same-race parents and has also been related to the states’ infant mortality rate by race.60

Observer identification is subject to other limitations. A research project on observer identification of race using photographs of multiracial faces found that observed race varies among observers and is influenced by the sex and racial identity of the observer.61 White and Asian men take relatively little time to categorize others, are the least likely to identify people as multiracial, and the most likely to identify people as black. On the other hand, multiracial observers tend to take a longer time to classify race and are more likely to designate people as multiracial.

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Identification by Self Versus Observer

Data collection for census or official purposes necessarily rely on self-reporting of identity, while research projects can apply either method of identification. The American National Election Studies, a US research center for collecting data on voting, public opinion, and political participation, used observer identification of respondents’ race until 2002.62

The classification of ancestry by various means (self, proxy, interviewer) in a sample of the US population surveyed in the First National Health and Nutrition Examination Survey (NHANES, 1971–1975) was more likely to vary for persons with multiracial backgrounds.63 Self- and observer classification was found to have low correspondence for American Indians.

The variability of racial identity by self- versus observer-reporting was demonstrated in the US Health Interview Survey of 1978, during which both methods were applied. Six percent of self-reported black, 29% of self-reported Asian, 62% of self-identified American Indians, and 80% of those who perceived themselves as “other” were classified by the observer (interviewer) as white.64

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Invisible Groups

A special category of minority citizens are those without documentation. Illegal immigrants do not identify themselves and will not be available for identification by others. While the numbers of minorities without documentation are unknown, they are believed to be numerous in some countries; there are approximately 7 million illegal immigrants in the United States, representing approximately 10% of ethnic minorities in that country.65

Large groups of Roma in Europe lack either citizenship or documentation necessary for being officially or statistically “visible” (birth certificates, personal identity documents, local residence permits).25 Lack of documents makes not only research projects but also service provision exceedingly cumbersome, even though these groups are likely to have as many health problems (or more) as minorities with documentation.23,66

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How To Collect Data?

Communication is a vital issue when working with minorities. Sometimes there is a language barrier between researchers and the target population. The use of interpreters can increase rapport and communication, although at the expense of reduced structure. Conversely, a strict control of the communication process can reduce the volume and quality of information collected.67

When the target group is heterogeneous in terms of language and literacy, structured face-to-face interviews might yield the best approach, as shown in the survey by the UN Development Program of Roma in 5 countries in Eastern Europe.20 Difficulties of communication can occur even when researchers and respondents ostensibly share the same language. An attempt in the 1970s to include a direct question on ethnicity in the British census provoked such public resistance (due to improper wording) that such a question was not asked again until 1991.68

Tools validated in a given setting might not be appropriate for use in certain minority groups. For example, body mass index calculated from self-reported weight and height greatly underestimates the prevalence of obesity among Mexican Americans compared with European Americans and African Americans.69 An analysis of the validity of self-reported hypertension in the NHANES III showed that self-report was not appropriate for estimating trends in hypertension prevalence among Mexican-Americans.70 Principles of questionnaire validation in cross-cultural settings71 should be applied in cross-ethnic settings as well.72

Even if the barriers of identifying minorities and communicating with minorities can be overcome, the question still remains as to whether minorities will participate in health research projects. Racial/ethnic minorities have low participation rates in medical research projects.73–75 A major reason for nonparticipation is a lack of trust in institutions of medical care, research, and personnel—influenced by the infamous Tuskegee study, and shaped by prior personal encounters with medical care.76,77 Documented racial discrimination towards Roma people in the health care systems of several European countries has limited not only service provision23 but involvement of Roma in health research projects.

Such attitudes may be changing—at least in US minorities.77 Minority groups, mostly African-Americans and Hispanics, are as likely as nonminorities to participate in various intervention trials if they are invited to do so.78 Involving black Americans as implementers of research has been shown to be critically important in increasing the participation of black Americans in research studies.77 Trust and participation of minorities can be increased by the active involvement of their representatives not only in policy design and interventional projects47 but also in health research, especially if they participate in the preparation, conduct and analysis.15,79

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Challenges in Data Analysis and Interpretation

Analysis and interpretation of health data by race/ethnicity should be approached by attention to the importance of methodology, starting with the classification system. Changes in taxonomy require sophisticated methods to compare data recorded in one census with data from another.80,81

Researchers should also take into account the shifting meaning of racial/ethnic categories over time. For example, the term “Hispanic” was introduced in the US census in 1980, with the precise meaning contested ever since.82,83

It is a challenge to separate the effects of known health determinants and risk factors from the effects of unknown determinants represented by race/ethnicity.84 Socioeconomic status (SES) is a well-recognized confounder in relation to race/ethnicity and health outcomes. However, even if SES is taken into account, there can be variations in socioeconomic status categories (eg, quality differences between equal-level schooling), measurement error, or incomparable SES indicators that give rise to residual confounding.52,85 Furthermore, estimates of racial income inequality can depend on whether race is based on self-classification or observer classification.86

Diet in racial/ethnic groups might also appear as a confounder. For example a higher exposure to persistent pollutants and biotoxins among certain groups of Asian and Pacific Islanders was linked to much higher consumption of seafood.87

Epidemiologists aim to uncover etiologic relations between various biologic, environmental, cultural, and social factors, and health outcomes. Given the scientifically-ungrounded, heterogeneous, and fluid nature of race/ethnicity, race and ethnicity cannot be treated as if they were risk factors such as smoking or cholesterol level.37,39,79,83,84 Rather, race and ethnicity are proxy measures for a range of critically important health determinants including cultural factors, attitudes, beliefs, values, social network, social support, languages spoken, religion, diet, family traditions, rurality, and a sense of social exclusion.39,41,48,51,88–92 Epidemiologic research that includes racial/ethnic variations in health should aim to collect information on all these potential risk factors, rather than be content with the umbrella term of “race/ethnicity.” Multivariate analysis should be conducted to adjust for all factors known and hypothesized to be etiologically related to the outcome in question.84

Comprehensive analyses that include a wide range of risk factors have sometimes been able to account for racial/ethnic differences in health outcomes. For example, an international comparison of 8 white and 3 black populations did not find higher blood pressure levels in blacks, pointing to the weight of environmental factors.93

Furthermore, considerable differences in blood pressure and risk factors for coronary heart disease were uncovered within a supposedly homogenous ethnic group (“South Asian”) in the United Kingdom, revealing the shortcomings of aggregating data in ethnic groups.94,95

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Who Is Doing The Research?

Ethnocentricity is an important influence in health research. In the United States, debates on the innate versus imposed nature of health disparities between blacks and whites were taking place even 150 years ago, with different viewpoints depending on the racial identity of the parties. Black doctors generally argued that slavery and poor living conditions were the major causes of health disparities, while whites proposed genetic inferiority.39,96

The role of the ethnicity of the researcher was vividly illustrated by Senior and Bhopal52 in their analysis of mortality data in England and Wales. A research group of nonminority researchers had compared mortality in male Indian immigrants and the male population of England and Wales in 5 categories of disease, for which the standardized mortality ratios (SMRs) were 1.7–3.4 times higher in immigrants. The researchers failed to note that those 5 categories of death comprised only 4% of all deaths in immigrants. Another 5 causes of death—the SMRs of which were only marginally increased or lower among the immigrants—comprised 60% of all deaths in the immigrants, as noted by minority researchers.52

There have been examples for which Roma people have been successfully incorporated into research design and implementation. A recent survey of segregated living areas populated by Roma people in Hungary was modified on recommendations of participating Roma field workers who suggested surveying all segregated areas regardless of the ethnicity of its inhabitants. A recent health interview survey among Roma groups employing Roma interviewers resulted in a 92% response rate.92

These examples do not imply that one perspective is better than another; we believe any perspective based on valid data and open to being reshaped is acceptable. However, especially when working with minorities, researchers should be aware of their own perspectives and should aim at widening those perspectives by inviting persons into the project who identify with those to be investigated. Active participation of minorities in research projects is the optimal means to implement social justice, increase trust, and ensure the incorporation of minority perspectives, both in the research project and in the potential utilization of its results.32,47,79

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External race/ethnicity (as reported by an observer) has been prone to variations according to location, time, the observer, and the observed persons. Self-reported race/ethnicity is fluid, and inherently linked to the basic human right of people to reveal—or not reveal—their own racial/ethnic identity.

Classifications of race/ethnicity are socially constructed and depend on the social and geographic context. There is no scientific basis for standardizing these categories across all settings. Nevertheless, race and ethnicity will in all probability remain in use in census and official statistics. Their relative simplicity of application enables data-gathering for purposes of policy-making, such as developing and enforcing measures of positive discrimination. These benefits override shortcomings in data quality.

Even so, the use of “race,” “ethnicity,” or “minority” as variables in research projects should be justified explicitly. Utmost care should be taken to describe the methodology by which the target groups are defined, individuals accessed, and data collected. Analysis should adjust for all relevant confounders, among them socioeconomic position, environmental factors, rurality, diet, social capital, access to health care, and quality of care received. Race and ethnicity in epidemiologic research should be recognized as proxy measures for an as-yet-unknown set of health determinants of primary importance. Scientific investigation should aim at dissecting these proxy measures into separate, operationalizable and interpretable indicators.

To increase trust and implement the principle of social justice, persons racially/ethnically identifying with the target minority group should be involved in the research as co-workers; the results should be fed back to representatives of the target group or to the entire target group if possible. Finally, it should be made clear how the research project serves the interests of those researched.

In short, simplistic categorizations such as “race” and “ethnicity” lead to simplistic research conclusions and, sooner or later, to simplistic policy measures. These are certainly inappropriate in our world of ever increasing complexity.

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The authors thank Monika Devay, Birgit Fillies, Zaida Herrera-Ortiz, and Thierry Louvet for their help with translation of documents in French, Spanish, and German.



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