Identification of Aboriginal children using linked administrative data: Consequences for measuring inequalities.

AIM: The aim of this study was to examine the identification of Aboriginal children in multiple administrative datasets and how this may affect estimates of health and development. METHODS: Data collections containing a question about Aboriginal ethnicity: birth registrations, perinatal statistics, Australian Early Development Census and school enrolments were linked to datasets recording developmental outcomes: national literacy and numeracy tests (National Assessment Program - Literacy and Numeracy), Australian Early Development Census and perinatal statistics (birthweight) for South Australian children born 1999-2005 (n = 13 414-44 989). Six algorithms to derive Aboriginal ethnicity were specified. The proportions of children thus quantified were compared for developmental outcomes, including those scoring above the national minimum standard in year 3 National Assessment Program - Literacy and Numeracy reading. RESULTS: The proportion of Aboriginal children identified varied from 1.9% to 4.7% when the algorithm incremented from once to ever identified as Aboriginal, the latter using linked datasets. The estimates of developmental outcomes were altered: for example, the proportion of Aboriginal children who performed above the national minimum standard in year 3 reading increased by 12 percentage points when the algorithm incremented from once to ever identified as Aboriginal. Similar differences by identification algorithm were seen for all outcomes. CONCLUSIONS: The proportion of South Australian children identified as Aboriginal in administrative datasets, and hence inequalities in developmental outcomes, varied depending on which and how many data sources were used. Linking multiple administrative datasets to determine the Aboriginal ethnicity of the child may be useful to inform policy, interventions, service delivery and how well we are closing developmental gaps.

Coverage and accuracy of ethnicity data on three Asian ethnic groups in New Zealand.

OBJECTIVE: Detecting and eliminating ethnic disparities in access to and outcomes of healthcare relies on accurate ethnicity recording. Studies have shown that there are inaccuracies in ethnicity data in New Zealand and elsewhere. This study examined coverage and accuracy of ethnicity data for three Asian ethnic groups. METHODS: Student researchers from, or with links to, the ethnic groups concerned worked with communities to recruit participants. Names and dates of birth, length of residence in New Zealand and immigration status were recorded. Names and dates of birth were sent to the New Zealand Health Information Service, which attempted to link them with National Health Index ethnicity data. RESULTS: Only 72% of participants could be linked to an NHI number, and only 48% of those had their ethnicity recorded accurately. Linkage odds were lower for older people, and accuracy was higher for Chinese people compared to the other ethnicities. Length of residence and immigration status did not affect either coverage or accuracy. CONCLUSION: Most participants who could be linked had their ethnicity recorded in the broader category of "Asian", but accuracy was poor at the sub-group level. IMPLICATIONS: Extreme caution should be applied when examining data about sub-groups within the 'Asian' category.

[Informative value of craniometric data for ethno-racial studies].

Skull measurements differ in terms of discriminative and taxonomic value. Facial signs carry much more taxonomic information than neurocranial structures. Differences in the informative value of selected craniological complexes provide a rationale for differential approach to the interpretation of the results of ethno-racial studies.

Measuring ethnicity in New Zealand: developing tools for health outcomes analysis.

OBJECTIVE: This study examines the development of new tools for analysing links between ethnicity and health outcomes. In a New Zealand context, it focuses on (1) how ethnicity is increasingly articulated as a social construct, (2) how individuals belonging to more than one ethnic group have been recorded and reported in research, and (3) health research and policy implications of the growing proportion of New Zealanders who claim multi-ethnic affiliations. DESIGN: New Zealand provides a microcosm in which to consider ethnicity, indigeneity, migration and intermarriage, and their interacting effects on society, culture, identity and health outcomes. Against a backdrop of historical debates about the measurement of race, and then ethnicity, the paper explores recent changes in the recording and reporting of ethnicity in the five-yearly Census of Population and Dwellings, and in death registrations. These changes are then considered in relation to the study of ethnic health disparities and the development of policies to overcome them. RESULTS: In the 2001 Census, of those who responded to the ethnicity question, at a level 1 classification 7.9% gave more than one response. In relation to the indigenous people of New Zealand, of all those who recorded Maori as one or more of their ethnic groups, only 56% recorded Maori only. In the younger age groups, less than half the Maori ethnic group were Maori only. Single ethnic categories disguise considerable within-group diversity in outcomes. CONCLUSION: While single ethnic group disparity studies have been useful in the past, we suggest that more sophisticated ways of conceptualising and analysing ethnicity data in relation to health disparities are now required in New Zealand. Based on the New Zealand experience, we also suggest that as international migration continues, and as intermarriage becomes more frequent in most countries, there will be pressure to move from single group race-based measures towards culturally-based complex ethnicity measures.

High adult mortality among Hiwi hunter-gatherers: implications for human evolution.

Extant apes experience early sexual maturity and short life spans relative to modern humans. Both of these traits and others are linked by life-history theory to mortality rates experienced at different ages by our hominin ancestors. However, currently there is a great deal of debate concerning hominin mortality profiles at different periods of evolutionary history. Observed rates and causes of mortality in modern hunter-gatherers may provide information about Upper Paleolithic mortality that can be compared to indirect evidence from the fossil record, yet little is published about causes and rates of mortality in foraging societies around the world. To our knowledge, interview-based life tables for recent hunter-gatherers are published for only four societies (Ache, Agta, Hadza, and Ju/'hoansi). Here, we present mortality data for a fifth group, the Hiwi hunter-gatherers of Venezuela. The results show comparatively high death rates among the Hiwi and highlight differences in mortality rates among hunter-gatherer societies. The high levels of conspecific violence and adult mortality in the Hiwi may better represent Paleolithic human demographics than do the lower, disease-based death rates reported in the most frequently cited forager studies.

Emergent properties in small-scale societies.

A multi-agent simulation is used to explore the relationship between the micro and the macro levels in small-scale societies. The simulation demonstrates, using an African hunter-gatherer group (the !Kung san) as a case study, the way in which population stability may arise from culturally framed, micro-level decision making by women about spacing of births. According to the simulation, population stability as an emergent property has different implications, depending on resource density. Data on Australian hunter-gatherer groups are presented that support the implications of the simulation. !Kung san micro-level cultural rules on incestuous marriages are shown to have macro-level consequences in the form of marriages between residential camps. Between-camp marriages have significant implications for access to resources and thereby for population dynamics of the group as a whole.

The evolution of social behavior in the prehistoric American southwest.

Long House Valley, located in the Black Mesa area of northeastern Arizona (USA), was inhabited by the Kayenta Anasazi from circa 1800 B.C. to circa A.D. 1300. These people were prehistoric precursors of the modern Pueblo cultures of the Colorado Plateau. A rich paleoenvironmental record, based on alluvial geomorphology, palynology, and dendroclimatology, permits the accurate quantitative reconstruction of annual fluctuations in potential agricultural production (kg maize/hectare). The archaeological record of Anasazi farming groups from A.D. 200 to 1300 provides information on a millennium of sociocultural stasis, variability, change, and adaptation. We report on a multi-agent computational model of this society that closely reproduces the main features of its actual history, including population ebb and flow, changing spatial settlement patterns, and eventual rapid decline. The agents in the model are monoagriculturalists, who decide both where to situate their fields and where to locate their settlements.

Unlocking the numerator-denominator bias. I: Adjustments ratios by ethnicity for 1991-94 mortality data. The New Zealand Census-Mortality Study.

AIM: To determine the extent of the under-reporting of Mäori and Pacific mortality among 0-74 year olds for the period 1991-94. METHODS: A subset (n=22,578) of highly probable linked 1991 census and 1991-94 mortality records were selected from the 31,635 census-mortality links in the New Zealand Census-Mortality Study. The numbers of decedents assigned as Mäori, Pacific, and non-Mäori non-Pacific were compared between mortality and census data. RESULTS: Compared to the death registration form, 29% more 0-74 year old decedents during 1991-94 had self-identified as sole-Mäori on the 1991 census (46% for prioritised-Mäori). This numerator-denominator bias was greater among the young and those living in central and southern New Zealand. Among 0-14, 15-24, 25-44, 45-64, and 65-74 year old decedents, respectively, 91%, 50%, 41%, 26% and 15% more decedents had self-identified as sole-Mäori on the 1991 census. For Northern, Midland, Central and Southern regional health authority areas, respectively, 14%, 17%, 81% and 102% more decedents had self-identified as sole-Mäori. Among Pacific decedents 68% more 0-74 year old decedents had self-identified as sole-Pacific on the 1991 census (78% for prioritised-Pacific group). This bias for Pacific decedents did not notably vary by age and region. CONCLUSIONS: This study confirms substantial underestimation of Mäori and Pacific mortality rates for the period 1991-94, even using the recommended sole-ethnic group denominator. The results from this study should be used to adjust ethnic-specific mortality rates for the early 1990s. Population-based funding formulas that included region-specific Mäori mortality rates would have particularly disadvantaged central and southern regions.

Unlocking the numerator-denominator bias. II: Adjustments to mortality rates by ethnicity and deprivation during 1991-94. The New Zealand Census-Mortality Study.

AIMS: Maori and Pacific mortality rates are underestimated due to different recording of ethnicity between mortality and census data--the so-called numerator-denominator bias. Ethnicity and deprivation are strongly associated with mortality in New Zealand, but it is unclear what are the independent and overlapping effects of each on health. The objectives of this study were first, to determine the effect of adjusting for numerator-denominator bias on ethnic-specific age-standardised all-cause mortality rates among 0-74 year olds during 1991-94: second, to determine the effect of adjusting for numerator-denominator bias on analyses of the independent associations of ethnic group and small area deprivation with all-cause mortality in New Zealand. METHODS: Direct standardisation methods were used to calculate rates of mortality by ethnic and small area deprivation groupings. RESULTS: Unadjusted for numerator-denominator bias, Maori had a 70% and 101% higher standardised mortality rate than non-Maori non-Pacific for males and females, respectively. Adjusting for numerator-denominator bias, the excess Maori mortality burden increased to 126% and 158%. For Pacific people, excess mortality increased from -5% and -13% (ie apparently lower mortality rates) to 58% and 54% after adjustment, for males and females respectively. Using data adjusted for numerator-denominator bias, about a third of the Maori to non-Maori non-Pacific disparity in mortality among 0-54 year olds was explained by small area deprivation. Conversely, about a quarter of the mortality gradient by deprivation in New Zealand was explained by ethnic group. CONCLUSIONS: Numerator-denominator bias causes a marked underestimate of the ethnic disparities in mortality in New Zealand for the 1991-4 period, both overall and within strata of deprivation. The distribution of small area deprivation by ethnicity explains some of the ethnic disparities in mortality.

Evaluación otorrinolaringológica en cinco etnias de la república mexicana / O.R.L. evaluation in five indigenous mexican ethnic groups

Se efectuó un estudio transversal, descriptivo y observacional en cinco etnias de la república mexicana para su evaluación otorrinolaringológica. Se encontró una incidencia global de defectos auditivos del 29.36 por ciento y 305 pacientes con algún tipo de patología otorrinolaringológica (55.96 por ciento), de los cuales la mayor incidencia fue la otitis media serosa (9.27 por ciento). De 545 pacientes estudiados se pudo establecer la necesidad de tratamiento quirúrgico en 106 casos (19.44 por ciento) y de estos prenominaron los tubos de ventilación (9.72 por ciento)