White Subgroups Research Articles

Ethnic-specific obesity cutoffs for diabetes risk: cross-sectional study of 490,288 UK biobank participants.

To compare the relationship between adiposity and prevalent diabetes across ethnic groups in the UK Biobank cohort and to derive ethnic-specific obesity cutoffs that equate to those developed in white populations in terms of diabetes prevalence. UK Biobank recruited 502,682 U.K. residents aged 40-69 years. We used baseline data on the 490,288 participants from the four largest ethnic subgroups: 471,174 (96.1%) white, 9,631 (2.0%) South Asian, 7,949 (1.6%) black, and 1,534 (0.3%) Chinese. Regression models were developed for the association between anthropometric measures (BMI, waist circumference, percentage body fat, and waist-to-hip ratio) and prevalent diabetes, stratified by sex and adjusted for age, physical activity, socioeconomic status, and heart disease. Nonwhite participants were two- to fourfold more likely to have diabetes. For the equivalent prevalence of diabetes at 30 kg/m(2) in white participants, BMI equated to the following: South Asians, 22.0 kg/m(2); black, 26.0 kg/m(2); Chinese women, 24.0 kg/m(2); and Chinese men, 26.0 kg/m(2). Among women, a waist circumference of 88 cm in the white subgroup equated to the following: South Asians, 70 cm; black, 79 cm; and Chinese, 74 cm. Among men, a waist circumference of 102 cm equated to 79, 88, and 88 cm for South Asian, black, and Chinese participants, respectively. Obesity should be defined at lower thresholds in nonwhite populations to ensure that interventions are targeted equitably based on equivalent diabetes prevalence. Furthermore, within the Asian population, a substantially lower obesity threshold should be applied to South Asian compared with Chinese groups.

Sociodemographic and hispanic acculturation factors and isolated anotia/microtia.

It has been observed in several studies that infants with anotia/microtia are more common among Hispanics compared with other racial/ethnic groups. We examined the association between selected Hispanic ethnicity and acculturation factors and anotia/microtia in the National Birth Defects Prevention Study. We examined data from mothers of 351 infants with isolated anotia/microtia and 8435 unaffected infants from the National Birth Defects Prevention Study with an expected delivery date from 1997 to 2007. Sociodemographic, maternal, and acculturation factors (e.g., age, maternal education, household income, body mass index, gestational diabetes, folic acid, smoking, alcohol intake, study center, parental birthplace, and years lived in the United States, maternal language) were assessed as overall risk factors and also as risk factors among subgroups of Hispanics (United States- and foreign-born) versus non-Hispanic whites. Compared with non-Hispanic whites, both United States- and foreign-born Hispanic mothers demonstrated substantially higher odds of delivering infants with anotia/microtia across nearly all strata of sociodemographic and other maternal factors (adjusted odds ratios range: 2.1-11.9). The odds of anotia/microtia was particularly elevated among Hispanic mothers who emigrated from Mexico after age five (adjusted odds ratios = 4.88; 95% confidence interval = 2.93-8.11) or who conducted the interview in Spanish (adjusted odds ratios = 4.97; 95% confidence interval = 3.00-8.24). We observed that certain sociodemographic and acculturation factors are associated with higher risks of anotia/microtia among offspring of Hispanic mothers.

Classification Tree Analysis of Race-Specific Subgroups at Risk for a Central Venous Catheter–Related Bloodstream Infection

Studies of racial disparities in patient safety events often do not use race-specific risk adjustment and do not account for reciprocal covariate interactions. These limitations were addressed by using classification tree analysis separately for black patients and white patients to identify characteristics that segment patients who have increased risks for a venous catheter-related bloodstream infection. A retrospective, cross-sectional analysis of 5,236,045 discharges from 103 Florida acute hospitals in 2005-2009 was conducted. Hospitals were rank ordered on the basis of the black/white Patient Safety Indicator (PSI) 7 rate ratio as follows: Group 1 (white rate higher), Group 2, (equivalent rates), Group 3, (black rate higher), and Group 4, (black rate highest). Predictor variables included 26 comorbidities (Elixhauser Comorbidity Index) and demographic characteristics. Four separate classification tree analyses were completed for each race/hospital group. Individual characteristics and groups of characteristics associated with increased PSI 7 risk differed for black and white patients. The average age for both races was different across the hospital groups (p < .01). Weight loss was the strongest single delineator and common to both races. The black subgroups with the highest PSI 7 risk were Medicare beneficiaries who were either < or = 25.5 years without hypertension or < or = 39.5 years without hypertension but with an emergency or trauma admission. The white subgroup with the highest PSI 7 risk consisted of patients < or = 45.5 years who had congestive heart failure but did not have either hypertension or weight loss. Identifying subgroups of patients at risk for a rare safety event such as PSI 7 should aid effective clinical decisions and efficient use of resources and help to guide patient safety interventions.

Does 5HTTLPR long allele prevent hospitalization? Test of Hardy–Weinberg equilibrium

Many studies suggest an association of the serotonin transporter gene polymorphism (5HTTLPR) long allele with better antidepressant treatment response than the short allele. However, there is controversy over these findings. We hypothesized that if the long allele is associated with a better outcome, we would find fewer inpatients with the long allele compared with the short allele. Chart review identified 925 depressed inpatients and 201 outpatients genotyped for 5HTTLPR. The sample was primarily White (>90%). We tested potential departures from Hardy-Weinberg equilibrium for each sample. We analyzed three independent sets of inpatient samples separately and combined, a White subgroup of 791 patients of the total 925 inpatients, and 201 outpatients. There was no departure from Hardy-Weinberg equilibrium with any of these samples. We also compared 5HTTLPR genotype prevalence between 925 inpatients and 201 outpatients, which showed no statistically significant difference.

Associations between γ-glutamyltransferase (GGT) and biomarkers of atherosclerosis: The multi-ethnic study of atherosclerosis (MESA)

ObjectiveTo evaluate associations between total serum γ-glutamyltransferase activity (GGT) and biomarkers of arteriosclerosis in the Multi-Ethnic Study of Atherosclerosis (MESA), including 6783 participants from four ethnic subgroups, i.e., White, Chinese, Black and Hispanic. MethodsAssociations between fasting total serum GGT activity and oxidized low-density lipoproteins (oxLDL), interleukin-6 (IL-6), C-reactive protein (CRP), and soluble intercellular adhesion molecule-1 (sICAM-1) were assessed. Following evaluation of linear trends between GGT and biomarkers of interest, multivariable linear regression models were serially adjusted for age, gender, site, ethnicity (M1); M1+lifestyle variables (M2); M2+traditional cardiovascular risk factors plus medications (M3); and M3+metabolic status (M4). Interactions were evaluated between GGT and age and ethnicity in all models. ResultsLinear trends were positive and significant between GGT and oxLDL, IL-6, CRP and sICAM-1 in crude models, and trends remained significant in all ethnic subgroups for CRP (p<0.0001) and sICAM-1 (p<0.001), and for IL-6 except in the Chinese. Trends between GGT and oxLDL were significant in the entire cohort and the White subgroup (p<0.0001), but not in other ethnic subgroups. Multivariable models demonstrated continuous strong, positive associations between GGT and CRP, IL-6 and sICAM-1. Associations between GGT and oxLDL were attenuated upon adjustment for LDL-C and other traditional risk factors. All models were attenuated with adjustment for metabolic status. No age interactions were evident. ConclusionsOur findings support the hypothesis that total serum GGT activity represents the impact of metabolic disease on vascular injury and atherosclerosis.

Racial/ethnic subgroup differences in cognitive ability test range restriction: Implications for differential validity.

Recent meta-analyses demonstrated that the observed correlation between cognitive ability test scores and performance criteria was lower for Black and Hispanic subgroups than for Asian and White subgroups in college admissions, civilian employment, and military domains (i.e., differential validity). Given mean score differences between racial/ethnic subgroups, these observed validities may have been confounded by subgroup differences in range restriction. The present study draws on data from hundreds of cognitive ability test validity studies including more than 1 million persons to investigate whether Asian, Black, Hispanic, and White subgroups have differed in amounts of range restriction. We first replicated observed differential validity results and also extended them by presenting the first meta-analytic evidence that observed cognitive ability test validity is lower for the Hispanic subgroup in civilian employment settings. All subgroups were approximately equivalently restricted in range in college admissions and civilian employment domains, but the Black subgroup was more restricted in range than the White subgroup in military studies. In all 3 domains, any differences in range restriction could not account for observed validity differences between subgroups. We also provide estimates of range-restriction-corrected validities; Black and Hispanic subgroups' corrected validities were 11.3-18.0% lower than White corrected validities across domains.

Gender disparities in utilization and outcome of comprehensive substance abuse treatment among racial/ethnic groups

This study examined gender differences within Black, Latino, and White subgroups in the utilization of comprehensive services and their relation to posttreatment substance use. Survey data were collected during the National Treatment Improvement Evaluation Study (NTIES), a prospective, longitudinal, multisite study of substance abuse treatment programs and their clients in the United States. The analytic sample consisted of 1,812 Blacks (734 women and 1,078 men), 486 Latinos (147 women and 339 men), and 844 Whites (147 women and 339 men) from 59 service delivery organizations. Results related to service utilization indicated that compared to men, women in all racial and ethnic groups needed and received more services targeted to their needs and reported more positive relations with service providers. Gender was a significant moderator of the relationship between service receipt and treatment outcomes for all racial and ethnic groups, but especially for the Latino subsample. Findings point to the need to consider race-specific gender differences in the development of culturally competent, comprehensive substance abuse treatment.

Duration of untreated psychosis in adolescents: Ethnic differences and clinical profiles

BackgroundDuration of Untreated Psychosis (DUP) is an important measure associated with outcome of psychosis. This first study in the UK compared DUP between adolescent and adult-onset individuals and explored whether the adolescent-onset group showed variations in DUP that could be accounted for by sociodemographic and selected risk factors. MethodsThis naturalistic cohort study included 940 new first-episode psychosis cases aged 14–35years (136 adolescent-onset versus 804 adult-onset psychotic individuals) referred to nine Early Intervention Services for Psychosis in London (2003–2009). Sociodemographic characteristics, age of onset, family history of mental illness, duration of untreated psychosis, suicidality and substance use information were collected at entry to the services. ResultsAdolescents presented with significantly greater median DUP (179days) than adults (81days, p=0.005). Large differences in DUP were found amongst adolescent ethnic groups (median DUP: White: 454days; Black: 103days; Asian and mixed: 28.5days). In addition, younger age of onset and higher lifetime cannabis use were associated with longer treatment delay amongst adolescents. ConclusionsThis study of DUP in adolescent-onset psychosis found it to be approximately twice the length of DUP amongst adults. For the adolescent White sub-group, DUP was far greater than the UK Department of Health target (<3months). Both the high rates of lifetime cannabis use and the lower age of onset might explain the long DUP in this ethnic group. Physicians need to be particularly vigilant about identifying and managing early psychosis in adolescents.

Can racial/ethnic subgroup criterion‐to‐test standard deviation ratios account for conflicting differential validity and differential prediction evidence for cognitive ability tests?

Differential validity and differential prediction analyses have come to conflicting conclusions regarding whether the relationship between cognitive ability tests and performance is the same across racial/ethnic subgroups. A prominent criticism of differential validity analyses is that they are confounded by subgroup differences in the ratio of criterion‐to‐test standard deviations (SDs). We investigated whether subgroup differences in these ratios can account for this conflicting evidence. Drawing on data from over 1 million participants, we find that subgroup differences in criterion‐to‐test SD ratios in general only account for a relatively small portion of subgroup differences in test‐criterion correlations.Practitioner points Cognitive ability tests exhibit differential validity for Asian, Black, Hispanic, and White subgroups. In most domains, subgroup differences in criterion‐to‐test SD ratios only account for a relatively small portion of these validity differences and thus do not explain why validities differ across subgroups. Still, because a portion of the already‐small validity differences are accounted for by SD ratios, the magnitude of any subgroup regression slope differences is small and is unlikely to result in underprediction of criterion performance for Asian, Black, and Hispanic subgroups.

Role of APOE Genotype in Gait Decline and Disability in Aging

Although apolipoprotein E (APOE) genetic variation may influence risk of gait decline and disability in aging through multiple mechanisms, a systematic examination of this relationship has been lacking. Our objective was to quantify the risk of gait decline and disability associated with the APOE ε4 allele in aging. We evaluated 627 community-dwelling adults aged 70 and older (white 67.8%) with APOE genotype and quantitative gait measurements participating in the Einstein Aging Study over a median follow-up of 3.0 years. Main outcomes were gait speed decline (cm/s/year) and incident disability. APOE ε4 allele frequency was 24.1%. Presence of APOE ε4 was not significantly associated with gait speed decline overall (p = .37) but was associated with faster gait speed decline in older men (estimate: -1.16, 95% CI: -2.31 to -0.01, p = .04). The interaction between the ε4 allele and male sex predicted gait speed decline (estimate: -1.70, 95% CI: -3.33 to -0.07, p = .04). Presence of the APOE ε4 allele was associated with increased risk of disability in older men (HR 3.72, 95% CI: 1.44-9.59, p = .007). Associations of the ε4 allele with study outcomes remained significant even after accounting for several potential confounders including vascular and cognitive status. The strength of the associations was stronger in the white subgroup. This preliminary report suggests that the APOE ε4 allele is associated with increased risk of gait speed decline and disability in older men.

Disparate patterns of hospitalisation reflect unmet needs and persistent ethnic inequalities in mental health care: the Scottish health and ethnicity linkage study

ObjectivesThe presence and extent of mental health inequalities in Scotland is unclear. We investigated ethnic variations in psychiatric hospitalisations and compulsory treatment in relation to socioeconomic indicators.DesignIn a retrospective cohort study design, using data linkage methods, we examined ethnic variations in psychiatric [any psychiatric, mood (affective), and psychotic disorders) hospitalisations and use of the Mental Health (Care and Treatment) (Scotland) Act 2003 (Emergency Detentions (ED), Short-Term Detentions (STD) and Compulsory Treatment Orders (CTO)] using age (and sex for compulsory treatment), car ownership, and housing tenure adjusted risk ratios (RR). 95% CIs for the data below exclude the reference White Scottish group value (100).ResultsCompared to the White Scottish population, Other White British men and women had lower hospitalisation from any psychiatric disorder (RR = 77.8, 95% CI: 71.0–85.2 and 85.8, 95% CI: 79.3–92.9), mood disorder (91.2, 95% CI: 86.9–95.8 and 83.6, 95% CI: 75.1–93.1), psychotic disorder (67.1, 95% CI: 59.9–75.2 and 78.5, 95% CI: 67.6–91.1), CTO (84.6, 95% CI: 72.4–98.9) and STD (88.2, 95% CI: 78.6–99.0). Any Mixed Background women had higher hospitalisation from any psychiatric disorder (137.2, 95% CI: 110.9–169.6) and men and women had a higher risk of psychotic disorder (200.6, 95% CI: 105.7–380.7 and 175.5, 95% CI: 102.3–301.2), CTO (263.0, 95% CI: 105.4–656.3), ED (245.6, 95% CI: 141.6–426.1) and STD (311.7, 95% CI: 190.2–510.7). Indian women had lower risk of any psychiatric disorder (43.2, 95% CI: 28.0–66.7). Pakistani men had lower risk of any psychiatric disorder (78.7, 95% CI: 69.3–89.3), and higher risk of mood disorders (117.5, 95% CI: 100.2–137.9). Pakistani women had similar risk of any psychiatric and mood disorder however, a twofold excess risk of psychotic disorder (227.3, 95% CI: 195.8–263.8). Risk of STD was higher in South Asians (136.9, 95% CI: 109.0–171.9). Chinese men and women had the lowest risk of hospitalisation for any psychiatric disorder (35.3, 95% CI: 23.2–53.7 and 44.5, 95% CI: 30.3–65.5) and mood disorder (51.5, 95% CI: 31.0–85.4 and 47.5, 95% CI: 23.2–97.4) but not psychotic disorders and higher risk for CTO (181.4, 95% CI: 121.0–271.0). African women had higher risk of any psychiatric disorder (139.4, 95% CI: 119.0–163.2). African men and women had the highest risk for psychotic disorders (230.8, 95% CI: 177.8–299.5 and 240.7, 95% CI: 163.8–353.9) and were also overrepresented in STD (214.3, 95% CI: 122.4–375.0) and CTO (486.6, 95% CI: 231.9–1021.1). Differences in hospitalisations were not fully attenuated when adjusted for car ownership and housing tenure and the effect of these adjustments varied by ethnic group.ConclusionOur data show disparate patterns of psychiatric hospitalisations by ethnic group in Scotland providing new observations concerning the mental health care experience of Chinese, Mixed background and White subgroups not fully explained by socioeconomic indicators. For South Asian and Chinese groups in particular, our data indicate under and late utilisation of mental health services. These data call for monitoring and review of services.

Spatiotemporal distributions of ambient oxides of nitrogen, with implications for exposure inequality and urban design

Intra-urban differences in concentrations of oxides of nitrogen (NOx) and exposure disparities in the Tampa area were investigated across temporal scales through emissions estimation, dispersion modeling, and analysis of residential subpopulation exposures. A hybrid estimation method was applied to provide link-level hourly on-road mobile source emissions. Ambient concentrations in 2002 at 1 km resolution were estimated using the CALPUFF dispersion model. Results were combined with residential demographic data at the block-group level, to investigate exposures and inequality for select racioethnic, age, and income population subgroups. Results indicate that on-road mobile sources contributed disproportionately to ground-level concentrations and dominated the spatial footprint across temporal scales (annual average to maximum hour). The black, lower income (less than $40K annually), and Hispanic subgroups had higher estimated exposures than the county average; the white and higher income (greater than $60K) subgroups had lower than average exposures. As annual average concentration increased, the disparity between groups generally increased. However, for the highest 1-hr concentrations, reverse disparities were also found. Implications: Current studies of air pollution exposure inequality have not fully considered differences by time scale and are often limited in spatial resolution. The modeling methods and the results presented here can be used to improve understanding of potential impacts of urban growth form on health and to improve urban sustainability. Results suggest focusing urban design interventions on reducing on-road mobile source emissions in areas with high densities of minority and low income groups.

The Role of Range Restriction and Criterion Contamination in Assessing Differential Validity by Race/Ethnicity

Berry et al.’s (J Appl Psychol 96:881–906, 2011) meta-analysis of cognitive ability test validity data across employment, college admissions, and military domains demonstrated that validity is lower for Black and Hispanic subgroups than for Asian and White subgroups. However, Berry et al. relied on observed test-criterion correlations and it is therefore not clear whether validity differences generalize beyond observed validities. The present study investigates the roles that range restriction and criterion contamination play in differential validity. A large dataset (N > 140,000) containing SAT scores and college grades of Asian, Black, Hispanic, and White test takers was used. Within-race corrections for multivariate range restriction were applied. Differential validity analyses were carried out using freshman GPA versus individual course grades as criteria to control for the contaminating influence of individual differences between students in course choice. Observed validities underestimated the magnitude of validity differences between subgroups relative to when range restriction and criterion contamination were controlled. Analyses also demonstrate that validity differences would translate to larger regression slope differences (i.e., differential prediction). Subgroup differences in range restriction and/or individual differences in course choice cannot account for lower validity of the SAT for Black and Hispanic subgroups. Controlling for these factors increased subgroup validity differences. Future research must look to other explanations for subgroup validity differences. The present study is the first differential validity study to simultaneously control for range restriction and individual differences in course choice, and answers a call to investigate potential causes of differential validity.

Reviewing, Categorizing, and Analyzing the Literature on Black–White Mean Differences for Predictors of Job Performance: Verifying Some perceptions and Updating/Correcting Others

In both theoretical and applied literatures, there is confusion regarding accurate values for expected Black–White subgroup differences in personnel selection test scores. Much confusion arises because empirical estimates of standardized subgroup differences (d) are subject to many of the same biasing factors associated with validity coefficients (i.e., d is functionally related to a point‐biserial r). To address such issues, we review/cumulate, categorize, and analyze a systematic set of many predictor‐specific meta‐analyses in the literature. We focus on confounds due to general use of concurrent, versus applicant, samples in the literature on Black–White d. We also focus on potential confusion due to different constructs being assessed within the same selection test method, as well as the influence of those constructs on d. It is shown that many types of predictors (such as biodata inventories or assessment centers) can have magnitudes of d that are much larger than previously thought. Indeed, some predictors (such as work samples) can have ds similar to that associated with paper‐and‐pencil tests of cognitive ability. We present more realistic values of d for both researcher and practitioner use. Implications for practice and future research are noted.

Racial Group Comparisons of Conceptualizations of Rap Music Constructs: A Cross-racial Validity Study of the Rap Music Attitude and Perception Scale

Interpretations and perceptions of the effects and content of rap music lyrics have been given considerable attention in the literature in recent years, yet few assessment tools have been developed that can produce reliable and valid inferences about these views. One exception is the Rap-music Attitude and Perception (RAP) Scale. This study examined the cross-racial effects on attitudes toward and perceptions of rap music using a sample of 1,254 college students. A cross-sectional survey design was used to gather these data. Three specific hypotheses were tested and were supported or partially supported. Alpha reliabilities for the full scale and for each of the three sub-scales were good for black and white students separately. Criterion validity for these groups was also good. Finally, tests of factorial equivalence suggested that the factor structure of the RAP was equivalent across racial groups. The RAP is a tool with strong psychometric properties and can be used by practitioners and researchers working with black and white subgroups. Directions for future research on the utility of the RAP are forwarded.

Crossvalidation of Two Heart Rate–based Equations for Predicting V[Combining Dot Above]O2max in White and Black Men

The purpose of this investigation was to crossvalidate 2 equations that use the ratio of maximal heart rate (HRmax) to resting HR (HRrest) for predicting maximal oxygen consumption (VO2max) in white and black men. One hundred and nine white (n = 51) and black (n = 58) men completed a maximal exercise test on a treadmill to determine VO2max. The HRrest and HRmax were used to predict VO2max via the HRindex and HRratio equations. Validity statistics were done to compare the criterion versus predicted VO2max values across the entire cohort and within each race separately. For the entire group, VO2max was significantly overestimated with the HRindex equation, but the HRratio equation yielded no significant difference compared with the criterion. In addition, there were no significant differences shown between VO2max and either HR-based prediction equation for the white subgroup. However, both equations significantly overestimated VO2max in the black group. Furthermore, large standard error of estimates (ranging from 6.92 to 7.90 ml·kg(-1)·min(-1)), total errors (ranging from 8.30 to 8.62 ml·kg(-1)·min(-1)), and limits of agreement (ranging from upper limits of 16.65 to lower limits of -18.25 ml·kg(-1)·min(-1)) were revealed when comparing the predicted to criterion VO2max for both the groups. Considering the results of this investigation, the HRratio and HRindex methods appear to crossvalidate and prove useful for estimating the mean VO2max in white men as a group but not for an age-matched group of black men. However, because of inflated values for error, caution should be exercised when using these methods to predict individual VO2max.

Student Attendance, Mobility, and Mathematics Achievement in an Urban School District

ABSTRACT The authors aim to describe student attendance–mobility within a large urban district in ways that are meaningful and useful to schools and the community. First, the prevalence of mobility and nonattendance in Grades 1–12 across all students and by gender, ethnicity, and socioeconomic subgroups is presented. Second, the impact on student mathematics achievement is examined. Results show that nonattendance–mobility negatively impact mathematics achievement as measured by the state's assessment, even after controlling for socioeconomic status and gender. Interestingly, there is not a differential impact across ethnicities. Black and White subgroups show similar patterns of achievement across attendance and mobility levels. Finally, the authors take a closer look at the 10 district high schools to determine where nonattendance–mobility is of particular concern. Implications for districts are discussed in terms of targeting the extent of the problem and where it is occurring, using that information to improve attendance and reduce mobility, and finally, instituting systematic approaches to deal with student movement in and out of schools.

Updating the trainability tests literature on Black–White subgroup differences and reconsidering criterion-related validity.

A number of applied psychologists have suggested that trainability test Black–White ethnic group differences are low or relatively low (e.g., Siegel & Bergman, 1975), though data are scarce. Likewise, there are relatively few estimates of criterion-related validity for trainability tests predicting job performance (cf. Robertson & Downs, 1989). We review and clarify the existing (and limited) literature on Black–White group differences on trainability tests, provide new trainability test data from a recent video-based trainability exam, and present archival data about how trainability test scores relate to cognitive ability, Black–White differences, and job performance. Consistent with hypotheses, our results suggest large correlations of trainability tests with cognitive ability (e.g., .80) and larger standardized ethnic group differences than previously thought (ds of 0.86, 1.10, and 1.21 for 3 samples). Results also suggest that trainability tests have higher validity than previously thought. Overall, our analysis provides a substantial amount of data to update our understanding of the use of trainability tests in personnel selection.

Association Between Interleukin‐6 −174 Polymorphism and Aggregatibacter actinomycetemcomitans in Chronic Periodontitis

We previously demonstrated an association between interleukin-6 (IL-6) polymorphisms and the detection of periodontopathogenic bacteria in aggressive and chronic periodontitis on a patient basis (pooled samples). The aim of this study is to comprehensively analyze the relative contribution of IL-6 genetic factors and local (tooth and site) factors on the detection of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) and Porphyromonas gingivalis in patients with chronic periodontitis. Forty patients diagnosed with severe chronic periodontitis had subgingival samples harvested from four sites (the deepest probing depths in each quadrant). All subjects had a blood sample taken to genotype the single nucleotide polymorphism at position -174 in the IL-6 gene promoter. Nested polymerase chain reaction analysis was performed on subgingival plaque samples for the detection of A. actinomycetemcomitans and P. gingivalis in each of the 160 sampled sites. The association between IL-6 -174 genotypes and bacterial detection was investigated with multilevel analysis accounting for the clustering of multiple sites analyzed within patients. Respectively 60%, 62%, and 40% of subjects had A. actinomycetemcomitans, P. gingivalis, and both bacteria concomitantly detected in ≥1 site. The multilevel analysis confirmed that, among all site and subject factors, IL-6 -174 G homozygosity showed the strongest association with the presence of A. actinomycetemcomitans in all subjects and in the subgroup of whites only. No associations were detected for P. gingivalis. This study provides further confirmatory evidence that the detection of A. actinomycetemcomitans is associated with IL-6 genetic factors in chronic periodontitis cases.

UNFAIR TREATMENT VS. CONFIRMATION BIAS? COMMENTS ON SANTELICES AND WILSON

ABSTRACTSantelices and Wilson (2010) claimed to have addressed technical criticisms of Freedle (2003) presented in Dorans (2004a) and elsewhere. Santelices and Wilson's abstract claimed that their study confirmed that SAT® verbal items do function differently for African American and White subgroups. In this commentary, I demonstrate that the Santelices and Wilson article provided no evidence to confirm differential item functioning (DIF) and failed to address my technical criticisms of Freedle. Instead, Santelices and Wilson contained several misrepresentations, including substituting “considered serious” for “more unusual” to describe an effect size and claiming to have studied four editions of the SAT when only two were actually studied. Central to its thesis was a hypothesis about DIF/difficulty correlations that was misattributed to Dorans. Santelices and Wilson based their argument for DIF on correlations between highly correlated variations on an index of DIF with item difficulty. While failing to demonstrate either unfairness in the test items or unfairness in the treatment of Freedle, Santelices and Wilson did contain evidence of confirmation bias.