Differential Item Functioning (DIF) and the Mini-Mental State Examination (MMSE)

Longitudinal Invariance and Construct Validity of the Chinese Version of the Mini-Mental State Examination Across 10 Years in the Elderly Population

Background and Purpose: In this study, we investigate the longitudinal measurement invariance of the Chinese version of the mini-mental state examination (CMMSE). Methods: The factor structure and longitudinal equivalence of the CMMSE were examined by confirmatory factor analysis. Four CMMSE measurements of 13,132 participants from the China Longitudinal Health and Longevity Study between 2008 and 2018 were included. The nested model of longitudinal invariance proves the existence of strict longitudinal invariance. Results: It showed that the factor structure, factor loadings, intercept error variance, and latent factor means of the CMMSE were invariant across four measurements. Conclusion: These findings indicate that the changes in CMMSE scores can be attributed to real structural change, indicating that the CMMSE is a reliable measurement tool for the study of cognitive aging.

The Effects of Aerobic and Resistance Exercises on the Cognitive and Physical Function of Persons with Mild Dementia: A Randomized Controlled Trial Protocol

Dementia causes deterioration in cognitive and physical functions. The scope of this study is to investigate the effect of different exercise programs on cognitive functions and functionality of persons suffering from mild Alzheimer's disease (AD) by generating information on the exercise types and their parameters. A randomized controlled trial (RCT) will be performed involving aerobic and resistance exercise interventions, taking place both at the sample collection center and at home. Participants will be randomly divided into two different intervention groups and a control group. All groups will be assessed twice; once at baseline and once after 12 weeks. The primary outcome shall comprise the effect of exercise programs on cognitive functions using cognitive testing, such as Addenbrooke's Cognitive Examination-Revisited (ACE-R), Mini Mental State Examination (MMSE), Trail Making Test A-Β (TMT A-B), and Digit Span Test (DST): Digit Span Forward (DSF) and Digit Span Backward (DSB). The effect on functionality will be assessed using the Senior Fitness Test (SFT), Berg Balance Scale (BBS), and Instrumental Activities of Daily Living Scale (IADL) questionnaire. Secondary outcomes include the effect of exercise on depression using the Geriatric Depression Scale-15 (GDS-15), on physical activity using the International Physical Activity Questionnaire (IPAQ), as well as the participants' compliance with the intervention. This study will investigate the possible effect of intervention of different exercise types and the comparison between them. Exercise forms a low-cost and reduced-risk intervention.

Multi-Disease Validation of the RUDAS for Cognitive Screening in Alzheimer's Disease, Parkinson's Disease, and Multiple Sclerosis

BACKGROUND

The Rowland Universal Dementia Assessment Scale (RUDAS) is a cognitive test with favorable diagnostic properties for detecting dementia and a low influence of education and cultural biases.

OBJECTIVE

We aimed to validate the RUDAS in people with Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS).

METHODS

We enrolled one hundred and fifty participants (60 with AD, 30 with PD, 60 with MS, and 120 healthy controls (HC)). All clinical groups completed a comprehensive neuropsychological battery, RUDAS, and standard cognitive tests of each disorder: MMSE, SCOPA-COG, and Symbol Digit Modalities Test. Intergroup comparisons between clinical groups and HC and ROC curves were estimated. Random Forest algorithms were trained and validated to detect cognitive impairment using RUDAS and rank the most relevant scores.

RESULTS

The RUDAS scores were lower in patients with AD, and patients with PD and MS showed cognitive impairment compared to healthy controls. Effect sizes were generally large. The total score was the most discriminative, followed by the memory score. Correlations with standardized neuropsychological tests were moderate to high. Random Forest algorithms obtained accuracies over 80-90% using the RUDAS for diagnosing AD and cognitive impairment associated with PD and MS.

CONCLUSION

Our results suggest the RUDAS is a valid test candidate for multi-disease cognitive screening tool in AD, PD, and MS.

Generation and age of immigration on later life cognitive performance in KHANDLE

OBJECTIVES

We examined the association of generational status and age at immigration with later life cognitive outcomes in a diverse sample of Latinos and Asian Americans.

DESIGN

Baseline data were obtained from the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) study, and a prospective cohort is initiated in 2017.

SETTING

Older adults in Northern California.

PARTICIPANTS

Our cohort consisted of Asians (n = 411) and Latinos (n = 340) who were on average 76 years old (SD = 6.8).

MEASUREMENTS

We used multivariable linear regression models to estimate associations between generational status and age at immigration (collapsed into one five-level variable) with measures of verbal episodic memory, semantic memory, and executive function, adjusting for age, gender, race and ethnicity, and own- and parental education.

RESULTS

Generational status and age at immigration were associated with cognitive outcomes in a graded manner. Compared to third-generation or higher immigrants, first-generation immigration in adulthood was associated with lower semantic memory (β = -0.96; 95% CI: -1.12, -0.81) than immigration in adolescence (β = -0.68; 95% CI: -0.96, -0.41) or childhood (β = -0.28; 95% CI: -0.49, -0.06). Moreover, immigration in adulthood was associated with lower executive function (β = -0.63; 95% CI: -0.78, -0.48) than immigration in adolescence (β = -0.49; 95% CI: -0.75, -0.23). Similarly, compared to third-generation individuals, first-generation immigrants had lower executive functioning scores.

CONCLUSIONS

Our study supports the notion that sociocontextual influences in early life impact later life cognitive scores. Longitudinal studies are needed to further clarify how immigration characteristics affect cognitive decline.

Socioeconomic Status, Race/Ethnicity, and Unexpected Variation in Dementia Classification in Longitudinal Survey Data

OBJECTIVES

As dementia affects a growing number of older adults, it is important to understand its detection and progression. We identified patterns in dementia classification over time using a longitudinal, nationally representative sample of older adults. We examined the relationship between socioeconomic status and race/ethnicity, and patterns in dementia classification.

METHODS

Data for 7,218 Medicare beneficiaries from the 2011-2017 National Health and Aging Trends Study (NHATS) were classified into five categories: consistently no dementia, consistently cognitive impairment, "typical" dementia progression, "expected" variation, and "unexpected" variation. Multivariable multinomial logistic regression assessed relative risk of dementia classification by sociodemographic and health factors.

RESULTS

Among NHATS respondents, 59.5% consistently were recorded as having no dementia, 7% consistently cognitively impaired, 13% as having typical progression, 15% as having expected variation, and 5.5% as having unexpected variation. In multivariable models, compared with consistent dementia classification, less education, Medicare-Medicaid-dual enrollment, and identifying as non-Hispanic Black were associated with increased likelihood of unexpected variation (e.g., non-Hispanic Black adjusted risk ratio: 2.12, 95% CI: 1.61-2.78, p < .0001).

DISCUSSION

A significant minority of individuals have unexpected patterns of dementia classification over time, particularly individuals with low socioeconomic status and identifying as non-Hispanic Black. Dementia classification uncertainty may make it challenging to activate resources (e.g., health care, caregiving) for effective disease management, underscoring the need to support persons from at-risk groups and to carefully evaluate cognitive assessment tools to ensure they are equally reliable across groups to avoid magnifying disparities.

Developing an Exposure Burden Score for Chemical Mixtures Using Item Response Theory, with Applications to PFAS Mixtures

BACKGROUND

There are few existing methods to quantify total exposure burden to chemical mixtures, independent of a health outcome. A summary metric could be advantageous for use in biomonitoring, risk assessment, health risk calculators, and mediation models.

OBJECTIVE

We developed a novel exposure burden score method for chemical mixtures, applied it to estimate exposure burden to per- and polyfluoroalkyl substances (PFAS) mixtures, and estimated associations of PFAS burden scores with cardio-metabolic outcomes in the general U.S.

POPULATION

METHODS

We applied item response theory (IRT) to biomonitoring data from 1,915 children and adults 12-80 years of age in the 2017-2018 National Health and Examination Survey to quantify a latent PFAS burden score, using serum concentrations of eight measured PFAS biomarkers, each considered an "item." The premise of IRT is that through using both information about a participant's concentration of an individual PFAS biomarker, as well as their exposure patterns for the PFAS mixture, we can estimate the participant's latent PFAS exposure burden, independent of a health outcome. We used linear regression to estimate associations of the PFAS burden score with cardio-metabolic outcomes and compared our findings to results using summed PFAS concentrations as the exposure metric.

RESULTS

PFAS burden scores and summed PFAS concentrations had moderate-high correlation (ρ=0.75). Isomers of PFOS [n-perfluorooctane sulfonic acid (n-PFOS) and perfluoromethylheptane sulfonic acid isomers (Sm-PFOS)] were the most informative to the PFAS burden scores. PFAS burden scores and summed PFAS concentrations were both significantly associated with cardio-metabolic outcomes, but associations were generally closer to the null for summed PFAS concentrations vs. the PFAS burden score. Adjusted associations (95% CIs) with total cholesterol (in milligrams per deciliter) were 8.6 (95% CI: 5.2, 11.9) and 2.4 (95% CI: 0.5, 4.2) per interquartile range increase in the PFAS burden score and summed concentrations, respectively. Sensitivity analyses showed similar associations with cardio-metabolic outcomes when only a subset of PFAS biomarkers was used to estimate PFAS burden. In a validation study, associations between PFAS burden scores and cholesterol were consistent with primary analyses but null when using summed PFAS concentrations.

DISCUSSION

IRT offers a straightforward way to include exposure biomarkers with low detection frequencies and can reduce exposure measurement error. Further, IRT enables comparisons of exposure burden to chemical mixtures across studies even if they did not measure the exact same set of chemicals, which supports harmonization across studies and consortia. We provide an accompanying PFAS burden calculator (https://pfasburden.shinyapps.io/app_pfas_burden/), enabling researchers to calculate PFAS burden scores based on U.S. population exposure reference ranges. https://doi.org/10.1289/EHP10125.

Description and clinical application of comprehensive geriatric assessment scales: A rapid systematic review of reviews

OBJECTIVE

This work aims to describe the main scales used in comprehensive geriatric assessment through a narrative analysis detailing their clinical application in relation to their advantages and disadvantages in terms of their psychometric properties (mental assessment) and biases in their application. The scales selected were: Barthel Index, Katz Index, Lawton and Brody Scale, Mini-Mental State Examination, Clock Test, Geriatric Depression Scale, and the Social Resources Scale.

METHODS

We conducted a rapid systematic review of reviews in MEDLINE (PubMed) up to January 2021, reporting findings using PRISMA, 2020. MeSH language, keywords, and the Boolean operators AND and OR were used to construct the reproducible search strategy.

RESULTS

Thirty-one works were selected that met the eligibility criteria: 18 systematic reviews, 12 literature reviews, and one scoping review. Multiple versions were found for some of the scales and biases in their interpretation were observed. Short, easy-to-administer questionnaires are recommended and cut-off points should be defined by formal education.

CONCLUSION

Comprehensive geriatric assessment scales are inexpensive, effective, and useful instruments for identifying problems and potential problems in the elderly. They should be easy to apply, not extensive, valid for multiple cultures and different levels of formal education, and applicable to individuals with different degrees of disability. It is recommended that health professionals be instructed in their use to avoid biases in the interpretation of the results.

Automated Analysis of Drawing Process to Estimate Global Cognition in Older Adults: Preliminary International Validation on the US and Japan Data Sets

BACKGROUND

With the aging of populations worldwide, early detection of cognitive impairments has become a research and clinical priority, particularly to enable preventive intervention for dementia. Automated analysis of the drawing process has been studied as a promising means for lightweight, self-administered cognitive assessment. However, this approach has not been sufficiently tested for its applicability across populations.

OBJECTIVE

The aim of this study was to evaluate the applicability of automated analysis of the drawing process for estimating global cognition in community-dwelling older adults across populations in different nations.

METHODS

We collected drawing data with a digital tablet, along with Montreal Cognitive Assessment (MoCA) scores for assessment of global cognition, from 92 community-dwelling older adults in the United States and Japan. We automatically extracted 6 drawing features that characterize the drawing process in terms of the drawing speed, pauses between drawings, pen pressure, and pen inclinations. We then investigated the association between the drawing features and MoCA scores through correlation and machine learning-based regression analyses.

RESULTS

We found that, with low MoCA scores, there tended to be higher variability in the drawing speed, a higher pause:drawing duration ratio, and lower variability in the pen's horizontal inclination in both the US and Japan data sets. A machine learning model that used drawing features to estimate MoCA scores demonstrated its capability to generalize from the US dataset to the Japan dataset (R²=0.35; permutation test, P<.001).

CONCLUSIONS

This study presents initial empirical evidence of the capability of automated analysis of the drawing process as an estimator of global cognition that is applicable across populations. Our results suggest that such automated analysis may enable the development of a practical tool for international use in self-administered, automated cognitive assessment.

The Impact of Education on Depression Assessment: Differential Item Functioning Analysis

A person's level of education can affect their access to health care, and their health outcomes. Increasing rates of depression are another looming public health concern. Therefore, vulnerability is compounded for individuals who have a lower level of education and depression. Assessment of depressive symptoms is integral to many domains of health care including primary care and mental health specialty care. This investigation examined the degree to which education influences the psychometric properties of self-report items that measure depressive symptoms. This study was a secondary data analysis derived from three large internet panel studies. Together, the studies included the Beck Depression Inventory-II, the Center for Epidemiologic Studies Depression Scale, the Patient Health Questionnaire, and the Patient Reported Outcomes Measurement Information System measures of depression. Using a differential item functioning (DIF) approach, we found evidence of DIF such that some items on each of the questionnaires were flagged for DIF with effect sizes ranging from McFadden's Pseudo R2 = .005 to .022. For example, results included several double-barreled questions flagged for DIF. Overall, questionnaires assessing depression vary in level of complexity, which interacts with the respondent's level of education. Measurement of depression should include consideration of possible educational disparities, to identify people who may struggle with a written questionnaire, or may be subject to subtle psychometric biases associated with education.

Factors associated with resident-to-resident elder mistreatment in nursing homes

BACKGROUND

Resident-to-resident elder mistreatment (RREM) in nursing homes has serious physical and psychological consequences, but factors related to RREM occurrence remain unclear. This study identifies individual and environmental characteristics associated with involvement in RREM episodes.

METHODS

The design was an observational study carried out in five urban and five suburban New York state nursing homes randomly selected on the basis of size and location. The sample consisted of 2011 residents in 10 facilities; 83% of facilities and 84% of eligible residents participated. RREM and potential correlates were identified through resident interviews, staff interviews, shift coupons, observation, chart review, and accident or incident reports.

RESULTS

A multivariate analysis controlling for relevant covariates found that individuals involved in RREM incidents exhibit milder dementia, show behavioral symptoms, and are less functionally impaired. Although special care units (SCU) for dementia have benefits for residents, one potential hazard for SCU residents is elevated risk for RREM.

CONCLUSIONS

Interventions to prevent and intervene in RREM incidents are greatly needed. The correlates identified in this research point to the need for targeted interventions, specifically for residents with milder impairment and with behavioral symptoms and individuals in SCUs.

Challenges in Measuring Applied Cognition: Measurement Properties and Equivalence of the Functional Assessment in Acute Care Multidimensional Computerized Adaptive Test (FAMCAT) Applied Cognition Item Bank

OBJECTIVE

To present challenges in assessment of applied cognition and the results of differential item functioning (DIF) analyses used to inform the development of a computerized adaptive test (CAT).

DESIGN

Measurement evaluation cohort study. DIF analyses of 107 items were conducted across educational, age, and sex groups. DIF hypotheses informed the evaluation of the results.

SETTING

Hospital-based rehabilitation from a single hospital system.

PARTICIPANTS

A total of 2216 hospitalized patients (N=2216).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Applied cognition item pool from multiple sources.

RESULTS

Many items were hypothesized to show DIF, particularly for age. Information was moderately high in the lower (cognitive disability) tail of the distribution, but some items were not informative. Reliability estimates were high (>0.89) across all studied groups, regardless of estimation method. There were 35 items with DIF of high magnitude and 19 with accompanying supportive hypotheses.

CONCLUSIONS

A key clinical tool in inpatient rehabilitation medicine is assessment of applied functional cognitive ability to inform patient-centered rehabilitation strategies to improve function. This was the first study to evaluate measurement equivalence of the applied cognition item pool across large samples of hospitalized patients. Although about one-third of the item pool evidenced DIF or low discrimination, results supported placement of most items into the bank and its use across groups differing in education, age, and sex. Six items were classified with salient DIF, defined as consistent DIF of high magnitude and or impact, with confirmatory directional DIF hypotheses, generated by content experts. These were recommended for adjustment or removal from the bank; 4 were deleted from the bank and 2 had lowered CAT exposure (administration frequency) rates. Many items hypothesized to show DIF contained content measuring constructs other than applied cognition such as physical frailty, perceptual difficulties, or skills reflective of greater educational attainment. Challenges in measurement of this construct are discussed.

The Colorado Cognitive Assessment (CoCA): Development of an Advanced Neuropsychological Screening Tool

OBJECTIVE

The Colorado Cognitive Assessment (CoCA) was designed to improve upon existing screening tests in a number of ways, including enhanced psychometric properties and minimization of bias across diverse groups. This paper describes the initial validation study of the CoCA, which seeks to describe the test; demonstrate its construct validity; measurement invariance to age, education, sex, and mood symptoms; and compare it to the Montreal Cognitive Assessment (MoCA).

METHOD

Participants included 151 older adults (MAge = 71.21, SD = 8.05) who were administered the CoCA, MoCA, Judgment test from the Neuropsychological Assessment Battery (NAB), 15-item version of the Geriatric Depression Scale (GDS-15), and 10-item version of the Geriatric Anxiety Scale (GAS-10).

RESULTS

A single-factor confirmatory factor analysis model of the CoCA fit the data well, CFI = 0.955; RMSEA = 0.033. The CoCA factor score reliability was .84, compared to .74 for the MoCA. The CoCA had stronger disattenuated correlations with the MoCA (r = .79) and NAB Judgment (r = .47) and weaker correlations with the GDS-15 (r = -.36) and GAS-10 (r = -.15), supporting its construct validity. Finally, when analyzed using multiple-indicators, multiple-causes (MIMIC) modeling, the CoCA showed no evidence of measurement noninvariance, unlike the MoCA.

CONCLUSIONS

These results provide initial evidence to suggest that the CoCA is a valid cognitive screening tool that offers numerous advantages over the MoCA, including superior psychometric properties and measurement noninvariance. Additional validation and normative studies are warranted.

Evaluating the cross-cultural validity of three family quality of life sub-scales

BACKGROUND

Families of children with disabilities often face unique challenges. Developed in a U.S. context, the Beach Center Family Quality of Life measure assesses the effectiveness of supports and services that families receive. This study examines whether items from three sub-scales of the Beach Center instrument perform similarly for two samples, one from Lusaka, Zambia, and the second from a Midwestern U.S. state.

METHODS

This cross-sectional research used secondary data and completed hierarchical ordinal regression analyses on item-level performance within the sub-scales.

RESULTS

Only one item flagged for potential item bias with remaining items performing similarly when controlling for overall sub-scale scores.

CONCLUSIONS

This study extends existing research on the cultural and linguistic appropriateness of the Beach Center measure, providing additional validity evidence about the internal structure of the scales. Findings indicate that these items are acceptable outcome measures for policy and programme evaluations in Zambia.

Healthcare utilization of Mexican-American Medicare beneficiaries with and without Alzheimer's disease and related dementias

Background

Older adults with Alzheimer’s disease and related dementias (ADRD) are high-risk to experience hospitalizations and emergency room (ER) admissions. Mexican-Americans have a high prevalence of ADRD, but there is limited information on the healthcare use of older Mexican-Americans with ADRD. We used data from a cohort of older Mexican-Americans that has been linked with Medicare files to investigate differences in hospitalizations, ER admissions, and physician visits according to ADRD diagnosis. We also identify sociodemographic, health, and functional characteristics that may contribute to differences in healthcare utilization between Mexican-American Medicare beneficiaries with and without an ADRD diagnosis.

Methods and findings

Data came from the Hispanic Established Populations for the Epidemiological Study of the Elderly that has been linked with Medicare Master Beneficiary Summary Files, Medicare Provider Analysis and Review files, Outpatient Standard Analytic files, and Carrier files. The final analytic sample included 1048 participants. Participants were followed for two years (eight quarters) after their survey interview. Generalized estimating equations were used to estimate the probability for one or more hospitalizations, ER admissions, and physician visits at each quarter. ADRD was associated with higher odds for hospitalizations (OR = 1.65, 95%CI = 1.29–2.11) and ER admissions (OR = 1.57, 95%CI = 1.23–1.94) but not physician visits (OR = 1.23, 95%CI = 0.91–1.67). The odds for hospitalizations (OR = 1.24, 95%CI = 0.97–1.60) and ER admissions (OR = 1.27, 95%CI = 1.01–1.59) were reduced after controlling for limitations in activities of daily living and comorbidities.

Conclusions

Mexican-American Medicare beneficiaries with ADRD had significantly higher odds for one or more hospitalizations and ER admissions but similar physician visits compared to beneficiaries without ADRD. Functional limitations and comorbidities contributed to the higher hospitalizations and ER admissions for older Mexican-Americans with ADRD.

DIF in the Spanish Version of the Verbal Selective Reminding Test Using Samples From Hispanics in the United States, Mexicans, and Spaniards

Aim

Before a test can be used in the target population, it is necessary to demonstrate that there is measurement equivalence. One way to do this is by studying differential item functioning (DIF).

Objective

In this study, we used the Mantel-Haenszel procedure and logistic regression to analyze DIF in the Spanish version of the Verbal Selective Reminding Test between Spaniards, Mexicans, and Hispanics in the United States.

Method

Three balanced samples, matched by age, education, and sex, were studied: Spaniards, Mexicans, and Hispanics [616 healthy participants from Spain (n = 211), Mexico (n = 201), and the United States (n = 205)]. A six-trial version of the Spanish version of the Verbal Selective Reminding Test was administered and scored according to standard procedures.

Results

Statistical analysis showed some DIF between the samples of Spaniards, Mexicans, and Hispanics. A bootstrap validation of results confirmed that the item pollo showed DIF: the Mexicans and Hispanics outperformed the Spaniards, holding a total score constant. The item oído also showed DIF and was remembered in greater measure by the Spaniards.

Conclusion

The Spanish version of the Verbal Selective Reminding Test can be used with Hispanic populations.

Mobility but Not Balance Limitations Are Associated With Cognitive Decline among Older Hispanics

Aging is associated with changes in lower-body functioning. The extent to which lower-body function is associated with cognitive changes over time is unclear, especially among older Hispanics, a high-risk population for declines in physical and cognitive functioning. We sought to determine if the association between lower-body functioning and cognitive decline over 9-years differentially varied with respect to balance, gait speed, lower-body strength (chair stands), or a summary score of the three measures. This retrospective cohort study used clinical performance data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly (H-EPESE). Cognitive function was measured using the Mini-Mental Status Exam. Linear mixed modeling was used to investigate the association between lower-body function and cognitive decline, controlling for patients' demographic and health characteristics. We found that gait speed and timed chair stands but not balance were associated with accelerated cognitive decline in Mexican-Americans age 75 years and older. These parameters of lower-body function can be feasibly measured in any clinic. As limitations in lower-body functioning may be an early marker of cognitive decline, this suggests an opportunity for the development of interventions to slow cognitive and physical disablement and promote successful aging among persons older than 75 years.

Differential item functioning in the cognitive screener used in the Longitudinal Aging Study in India

INTRODUCTION

The Longitudinal Aging Study in India (LASI) was initiated to capture data to be comparable to the Health and Retirement Survey (HRS) and hence used study instruments from the HRS. However, a rigorous psychometric evaluation before adaptation of cognitive tests may have indicated bias due to diversities across Indian states such as education, ethnicity, and urbanicity. In the present analysis, we evaluated if items show differential item functioning (DIF) by literacy, urbanicity, and education status.

METHODS

We calculated proportions for each item and weighted descriptive statistics of demographic characteristics in LASI. Next, we evaluated item-level measurement differences by testing for DIF using the alignment approach implemented using Mplus software.

OBSERVATION

We found that cognitive items in the LASI interview demonstrate bias by education and literacy, but not urbanicity. Items relating to animal (word) fluency show DIF. The model rates correct identification of the prime minister as the most difficult binary response item whereas the day of the week and numeracy items are rated comparatively easier.

CONCLUSIONS

Our study would facilitate comparison across education, literacy and urbancity to support analyses of differences in cognitive status. This would help future instrument development efforts by recognizing potentially problematic items in certain subgroups.

Cohort Differences in Cognitive Impairment and Cognitive Decline Among Mexican-Americans Aged 75 Years or Older

Research suggests that the prevalence and incidence of cognitive impairment among older adults is decreasing. This analysis used data from 9 waves (1993-2016) of the Hispanic Established Populations for the Epidemiologic Study of the Elderly to assess cognitive status and cognitive decline for 2 cohorts of Mexican-Americans aged ≥75 years in 1993-1994 versus 2004-2005. Logistic regression, joint longitudinal survival models, and illness-death models for interval-censored data were used to examine cohort differences in the odds of prevalent cognitive impairment, trajectories of cognitive decline, and the risk of 10-year incident cognitive impairment, respectively. Results indicated that compared with the 1993-1994 cohort, the 2004-2005 cohort had higher odds for prevalent cognitive impairment (odds ratio = 2.51, 95% confidence interval (CI): 1.92, 3.29), particularly among participants with <4 years of education (odds ratio = 2.99, 95% CI: 2.14, 4.18). Conversely, the 2004-2005 cohort exhibited significantly slower rates of cognitive decline (βˆ = 0.50, 95% CI: 0.39, 0.62) and had a significantly lower risk of incident cognitive impairment (hazard ratio = 0.75, 95% CI: 0.62, 0.91) compared with the 1993-1994 cohort. This analysis provides mixed results for cohort trends in the cognitive health of older Mexican-Americans. Continued research is needed to identify risk factors that contribute to these population-level trends.

Interpreting Mini-Mental State Examination Performance in Highly Proficient Bilingual Spanish-English and Asian Indian-English Speakers: Demographic Adjustments, Item Analyses, and Supplemental Measures

PURPOSE

Performance on the Mini-Mental State Examination (MMSE), among the most widely used global screens of adult cognitive status, is affected by demographic variables including age, education, and ethnicity. This study extends prior research by examining the specific effects of bilingualism on MMSE performance.

METHOD

Sixty independent community-dwelling monolingual and bilingual adults were recruited from eastern and western regions of the United States in this cross-sectional group study. Independent sample t tests were used to compare 2 bilingual groups (Spanish-English and Asian Indian-English) with matched monolingual speakers on the MMSE, demographically adjusted MMSE scores, MMSE item scores, and a nonverbal cognitive measure. Regression analyses were also performed to determine whether language proficiency predicted MMSE performance in both groups of bilingual speakers.

RESULTS

Group differences were evident on the MMSE, on demographically adjusted MMSE scores, and on a small subset of individual MMSE items. Scores on a standardized screen of language proficiency predicted a significant proportion of the variance in the MMSE scores of both bilingual groups.

CONCLUSIONS

Bilingual speakers demonstrated distinct performance profiles on the MMSE. Results suggest that supplementing the MMSE with a language screen, administering a nonverbal measure, and/or evaluating item-based patterns of performance may assist with test interpretation for this population.

Age of Migration and the Incidence of Cognitive Impairment: A Cohort Study of Elder Mexican-Americans

BACKGROUND AND OBJECTIVES

To explore nativity and age of migration differentials in the incidence of cognitive impairment among older Mexican-Americans.

RESEARCH DESIGN AND METHODS

We employ maximum-likelihood discrete time hazard models to estimate risk ratios of cognitive impairment in a sample of 2,708 Mexican-Americans 65 and older who were cognitively healthy at baseline over a follow-up period of up to 20 years.

RESULTS

Late-life immigrant women have a 46% higher risk of cognitive impairment compared to U.S.-born Mexican-American women. Conversely, midlife immigrant men have a 29% lower risk of cognitive impairment compared to U.S.-born Mexican-American men. The incidence of cognitive impairment did not differ for early-life and midlife immigrant women relative to U.S.-born women or for early- and late-life immigrant men compared to U.S.-born men.

DISCUSSION AND IMPLICATIONS

Differences in cognitive impairment risk between U.S.-born and foreign-born Mexican-American subgroups may be partly due to health selectivity. Cognitive impairment is more prevalent among immigrant groups which may result in a higher burden on family members and/or high dependency on public resources. Programs are needed that can detect decline at earlier stages and reduce the risk for cognitive impairment among older immigrants entering their last decades of life.

Bayesian Multilevel MIMIC Modeling for Studying Measurement Invariance in Cross-group Comparisons

BACKGROUND

Recent methodological advancements should catalyze the evaluation of measurement invariance across groups, which is required for conducting meaningful cross-group comparisons.

OBJECTIVE

The aim of this study was to apply a state-of-the-art statistical method for comparing latent mean scores and evaluating measurement invariance across managers' and frontline workers' ratings of the organization of hospital care.

METHODS

On the 87 nursing units in a single institution, French-speaking and Dutch-speaking nursing unit managers' and staff nurses' ratings of their work environment were measured using the multidimensional 32-item practice environment scale of the nursing work index (PES-NWI). Measurement invariance and latent mean scores were evaluated in the form of a Bayesian 2-level multiple indicators multiple causes model with covariates at the individual nurse and nursing unit level. Role (manager, staff nurse) and language (French, Dutch) are of primary interest.

RESULTS

Language group membership accounted for 7 of 11 PES-NWI items showing measurement noninvariance. Cross-group comparisons also showed that covariates at both within-level and between-level had significant effects on PES-NWI latent mean scores. Most notably, nursing unit managers, when compared with staff nurses, hold more positive views of several PES-NWI dimensions.

CONCLUSIONS

Using a widely used instrument for measuring nurses' work environment, this study shows that precautions for the potential threat of measurement noninvariance are necessary in all stages of a study that relies on survey data to compare groups, particularly in multilingual settings. A Bayesian multilevel multiple indicators multiple causes approach can accommodate for detecting all possible instances of noninvariance for multiple covariates of interest at the within-level and between-level jointly.

Effects of Education on Differential Item Functioning on the 15-Item Modified Korean Version of the Boston Naming Test

OBJECTIVE

Education is expected to have an effect on differential item functioning (DIF) on the 15-item Modified Boston Naming Test in the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet (BNT-KC). However, no study has examined DIF in the BNT-KC.

METHODS

We used the item response theory to investigate the impact of education on the DIF in the BNT-KC among elderly individuals with or without dementia (n=720). A two-parameter item response model was used to determine the difficulty and discrimination parameters of each item. The Benjamini-Hochberg procedure was used to address the risk of Type I errors on multiple testing.

RESULTS

Four items, "mermaid," "acorn," "compass," and "pomegranate" continued to demonstrate DIF after controlling for multiple comparisons. Those with low education levels were more likely to error on "mermaid" and "compass," while those with high education levels were more likely to error on "acorn" and "pomegranate." "Hand" and "red pepper" were too easily identified to be used for detecting dementia patients. "Monk's hat" and "pomegranate" were less discriminating than other items, limiting their usefulness in clinical setting.

CONCLUSION

These findings may provide useful information for the development of a revised version of the BNT-KC to help clinicians make diagnostic decisions more accurately.

Systematic review of dementia prevalence and incidence in United States race/ethnic populations

OBJECTIVE

To identify incidence and prevalence of dementia in racial and ethnic populations in the United States.

METHODS

A systematic review of literature.

RESULTS

A total of 1215 studies were reviewed; 114 were included. Dementia prevalence rates reported for age 65+ years from a low of 6.3% in Japanese Americans, 12.9% in Caribbean Hispanic Americans, 12.2% in Guamanian Chamorro and ranged widely in African Americans from 7.2% to 20.9%. Dementia annual incidence for African American (mean = 2.6%; SD = 1%; range, 1.4%-5.5%) and Caribbean Hispanic populations were significantly higher (mean, 3.6%; SD, 1.2%; range, 2.3%-5.3%) than Mexican American and Japanese Americans and non-Latino white populations (0.8%-2.7%), P < .001.

CONCLUSIONS

Data are needed for American Indian, most Asian, and Pacific Islander populations. Disaggregation of large race/ethnic classifications is warranted due to within-population heterogeneity in incidence and prevalence. African American and Caribbean Hispanic studies showed higher incidence of dementia. A nationwide approach is needed to identify communities at high risk and to tailor culturally appropriate services accordingly.

Relationship between metabolic and vascular conditions and cognitive decline among older Mexican Americans

OBJECTIVE

Metabolic and vascular conditions have been independently associated with dementia and cognitive decline among older adults, but research on the combined effects that these conditions have on cognitive decline, especially among older Mexican Americans, is lacking. The purpose of this study was to examine the relationship between metabolic and vascular conditions and cognitive decline among older Mexican Americans.

METHODS

The final sample included 2767 participants of the Hispanic Established Populations for the Epidemiologic Study of the Elderly. Linear mixed-effects regression was used to model cognitive decline across six examinations (1993-2007) according to the number (zero, one, two, and three to four) of metabolic and vascular conditions (hypertension, diabetes, stroke, and heart attack).

RESULTS

Of the 2767 participants included in the final sample, 777 had zero conditions, 1314 had one condition, 553 had two conditions, and 123 had three to four conditions. Participants with two or three to four conditions had significantly greater cognitive decline compared with participants with zero or one condition. Stroke had the largest effect size on cognitive decline based on the proportion of variance that stroke accounted for in the linear mixed-effects model.

CONCLUSION

Mexican American older adults with multiple metabolic and vascular conditions exhibit greater cognitive decline than those with zero or one condition. Public health interventions designed to reduce the prevalence of chronic metabolic and vascular conditions, in particular stroke, may limit the severity of cognitive decline among older Mexican Americans.

Re-assessing the dimensional structure of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE): empirical evidence for a shortened Brazilian version

BACKGROUND

The dimensional structure, effective number of item responses and item redundancies are controversial features of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) requiring more light. The aims of the present study are to revisit the dimensional structure and propose a shorter version of the instrument.

METHODS

The sample comprised 652 elderly and their informants, either attending a geriatric service of a public university clinic or enrolled in a health care provider database in Rio de Janeiro, Brazil. A Confirmatory Factor Analysis (CFA) first tested the originally proposed one-dimensional structure comprised of 26 items. This was followed by sequential Exploratory Structural Equation Model (ESEM) to evaluate alternative models, in particular a bi-dimensional solution. The identification of residual correlations (RC) lead to a shortened 20-item model, which was tested further via CFA.

RESULTS

The original model fitted poorly (RMSEA = 0.073; 90% CI: 0.069-0.077). Regarding the two-dimensional model, the exploratory procedure (ESEM) indicated several RCs and a lack of factor-based discriminant validity. The ensuing CFA on the one-dimensional model with freely estimated RCs showed an adequate fit (RMSEA = 0.051; 90% CI: 0.047-0.055). Addressing the identified RCs, the CFA on the abridged 20-item version also showed an adequate fit (RMSEA = 0.058; 90% CI: 0.053-0.064) and no further RCs.

CONCLUSION

A one-factor dimensional structure and a reduced version with 20 locally independent items were the most tenable solution. However, although promising, this simpler structure requires further examination before it may be fully supported and recommended.

Differential Item Functioning by Education and Sex in Subtests of the Repeatable Battery Assessment of Neuropsychological Status

The main objective of this study is to evaluate functions of the items changing with the gender and educational level in the List Learning and the Picture Naming subtests in the Repeatable Battery Assessment of Neuropsychological Status. The study was implemented on 315 volunteers consisting of 157 women and 158 males in the 20–79 age group with three different educational levels (107 graduates of primary school, 102 graduates of high school, and 106 graduates of university). Logistic Regression method was used to determine the items that included differential item functioning (DIF). As a result of the analyses, DIF was encountered in the Picture Naming that could cause bias in several items in levels B and C based on the gender and education variables. Although DIF was not found in the List Learning based on the gender variable, DIF was found in some items based on the education variable.

The European general practice research network presents the translations of its comprehensive definition of multimorbidity in family medicine in ten European languages

BACKGROUND

Multimorbidity, according to the World Health Organization, exists when there are two or more chronic conditions in one patient. This definition seems inaccurate for the holistic approach to Family Medicine (FM) and long-term care. To avoid this pitfall the European General Practitioners Research Network (EGPRN) designed a comprehensive definition of multimorbidity using a systematic literature review.

OBJECTIVE

To translate that English definition into European languages and to validate the semantic, conceptual and cultural homogeneity of the translations for further research.

METHOD

Forward translation of the EGPRN's definition of multimorbidity followed by a Delphi consensus procedure assessment, a backward translation and a cultural check with all teams to ensure the homogeneity of the translations in their national context. Consensus was defined as 70% of the scores being higher than 6. Delphi rounds were repeated in each country until a consensus was reached.

RESULTS

229 European medical expert FPs participated in the study. Ten consensual translations of the EGPRN comprehensive definition of multimorbidity were achieved.

CONCLUSION

A comprehensive definition of multimorbidity is now available in English and ten European languages for further collaborative research in FM and long-term care.

Evaluating the Mathematics Interest Inventory Using Item Response Theory

As the United States has begun to lag behind other developed countries in performance on mathematics and science, researchers have sought to explain this with theories of teaching, knowledge, and motivation. We expand this examination by further analyzing a measure of interest that has been linked to student performance in mathematics and intention to enroll in advanced mathematics classes. Using Item Response Theory (IRT), the purpose of this study was to evaluate the psychometric properties of the Mathematics Interest Inventory (MII). Six hundred sixty-six students (47.6% Hispanic, 48.2% Male) formed the sample. Results revealed minimal differential item functioning (DIF) between genders. Substantial DIF emerged between Hispanic and White students. Implications of the differential functioning and the measurement of interest in mathematics are discussed.

The association between health literacy and indicators of cognitive impairment in a diverse sample of primary care patients

OBJECTIVES

To confirm the association of health literacy scores as measured by Health Literacy Assessment Using Talking Touchscreen Technology (Health LiTT) with cognitive ability and education. To determine whether this association differs by cognitive task.

METHODS

Cognitive impairment was measured using the Mini-Cog, which combines a delayed word recall task (WRT) and a clock drawing task (CDT) to yield an overall classification of normal versus cognitively impaired. Participants were recruited from primary care clinics that provide care to underserved patients.

RESULTS

Participants (n=574) were predominantly non-Hispanic black (67%) with a mean age of 46 years, 50% did not have health insurance, 56% had a high school education or less and 21% screened positive for cognitive impairment. Overall cognitive ability and education were significantly associated with health literacy after adjusting for other variables, including race/ethnicity and physical health. We observed a stronger association between the CDT and health literacy than between the WRT and health literacy.

CONCLUSION

By confirming hypothesized associations, this study provides additional support of the validity of Health LiTT.

PRACTICE IMPLICATIONS

Health LiTT is a reliable and valid tool that researchers and clinicians can use to identify individuals who might have difficulty understanding health information.

Sources of variation on the mini-mental state examination in a population-based sample of centenarians

Centenarians represent a rare but rapidly growing segment of the oldest-old. This study presents item-level data from the Mini-Mental State Examination (MMSE) in a cross-sectional, population-based sample of 244 centenarians and near-centenarians (aged 98-108, 16% men, 21% African-American, 38% community dwelling) from the Georgia Centenarian Study (2001-2008) according to age, education, sex, race, and residential status. Multiple-Indicator Multiple-Cause (MIMIC) models were used to identify systematic domain-level differences in MMSE scores according to demographic characteristics in this age group. Indirect effects of age, educational attainment, race, and residential status were found on MMSE scores. Direct effects were limited to concentration for education and race and orientation for residential status. Mean levels of cognitive functioning in centenarians were low, with mean values below most commonly-used cutoffs. Overall scores on the MMSE differed as a function of age, education, race, and residential status, with differences in scale performance limited primarily to concentration and orientation and no evidence of interactions between centenarian characteristics. Adjusting for education was not sufficient to account for differences according to race, and adjusting for residential status was not sufficient to account for differences according to age.

Verbal and physical aggression directed at nursing home staff by residents

CONTEXT

Little research has been conducted on aggression directed at staff by nursing home residents.

OBJECTIVE

To estimate the prevalence of resident-to-staff aggression (RSA) over a 2-week period.

DESIGN

Prevalent cohort study.

SETTING

Large urban nursing homes.

PARTICIPANTS

Population-based sample of 1,552 residents (80 % of eligible residents) and 282 certified nursing assistants.

MAIN OUTCOME MEASURES

Measures of resident characteristics and staff reports of physical, verbal, or sexual behaviors directed at staff by residents.

RESULTS

The staff response rate was 89 %. Staff reported that 15.6 % of residents directed aggressive behaviors toward them (2.8 % physical, 7.5 % verbal, 0.5 % sexual, and 4.8 % both verbal and physical). The most commonly reported type was verbal (12.4 %), particularly screaming at the certified nursing assistant (9.0 % of residents). Overall, physical aggression toward staff was reported for 7.6 % of residents, the most common being hitting (3.9 % of residents). Aggressive behaviors occurred most commonly in resident rooms (77.2 %) and in the morning (84.3 %), typically during the provision of morning care. In a logistic regression model, three clinical factors were significantly associated with resident-to-staff aggression: greater disordered behavior (OR = 6.48, 95 % CI: 4.55, 9.21), affective disturbance (OR = 2.29, 95 % CI: 1.68, 3.13), and need for activities of daily living morning assistance (OR = 2.16, 95 % CI: 1.53, 3.05). Hispanic (as contrasted with White) residents were less likely to be identified as aggressors toward staff (OR = 0.57, 95 % CI: 0.36, 0.91).

CONCLUSION

Resident-to-staff aggression in nursing homes is common, particularly during morning care. A variety of demographic and clinical factors was associated with resident-to-staff aggression; this could serve as the basis for evidence-based interventions. Because RSA may negatively affect the quality of care, resident and staff safety, and staff job satisfaction and turnover, further research is needed to understand its causes and consequences and to develop interventions to mitigate its potential impact.

A staff intervention targeting resident-to-resident elder mistreatment (R-REM) in long-term care increased staff knowledge, recognition and reporting: results from a cluster randomized trial

BACKGROUND

Elder abuse in long-term care has received considerable attention; however, resident-to-resident elder mistreatment (R-REM) has not been well researched. Preliminary findings from studies of R-REM suggest that it is sufficiently widespread to merit concern, and is likely to have serious detrimental outcomes for residents. However, no evidence-based training, intervention and implementation strategies exist that address this issue.

OBJECTIVES

The objective was to evaluate the impact of a newly developed R-REM training intervention for nursing staff on knowledge, recognition and reporting of R-REM.

DESIGN

The design was a prospective cluster randomized trial with randomization at the unit level.

METHODS

A sample of 1405 residents (685 in the control and 720 in the intervention group) from 47 New York City nursing home units (23 experimental and 24 control) in 5 nursing homes was assessed. Data were collected at three waves: baseline, 6 and 12 months. Staff on the experimental units received the training and implementation protocols, while those on the comparison units did not. Evaluation of outcomes was conducted on an intent-to-treat basis using mixed (random and fixed effects) models for continuous knowledge variables and Poisson regressions for longitudinal count data measuring recognition and reporting.

RESULTS

There was a significant increase in knowledge post-training, controlling for pre-training levels for the intervention group (p<0.001), significantly increased recognition of R-REM (p<0.001), and longitudinal reporting in the intervention as contrasted with the control group (p=0.0058).

CONCLUSIONS

A longitudinal evaluation demonstrated that the training intervention was effective in enhancing knowledge, recognition and reporting of R-REM. It is recommended that this training program be implemented in long-term care facilities.

A systematic survey instrument translation process for multi-country, comparative health workforce studies

BACKGROUND

As health services research (HSR) expands across the globe, researchers will adopt health services and health worker evaluation instruments developed in one country for use in another. This paper explores the cross-cultural methodological challenges involved in translating HSR in the language and context of different health systems.

OBJECTIVES

To describe the pre-data collection systematic translation process used in a twelve country, eleven language nursing workforce survey.

DESIGN AND SETTINGS

We illustrate the potential advantages of Content Validity Indexing (CVI) techniques to validate a nursing workforce survey developed for RN4CAST, a twelve country (Belgium, England, Finland, Germany, Greece, Ireland, Netherlands, Norway, Poland, Spain, Sweden, and Switzerland), eleven language (with modifications for regional dialects, including Dutch, English, Finnish, French, German, Greek, Italian, Norwegian, Polish, Spanish, and Swedish), comparative nursing workforce study in Europe.

PARTICIPANTS

Expert review panels comprised of practicing nurses from twelve European countries who evaluated cross-cultural relevance, including translation, of a nursing workforce survey instrument developed by experts in the field.

METHODS

The method described in this paper used Content Validity Indexing (CVI) techniques with chance correction and provides researchers with a systematic approach for standardizing language translation processes while simultaneously evaluating the cross-cultural applicability of a survey instrument in the new context.

RESULTS

The cross-cultural evaluation process produced CVI scores for the instrument ranging from .61 to .95. The process successfully identified potentially problematic survey items and errors with translation.

CONCLUSIONS

The translation approach described here may help researchers reduce threats to data validity and improve instrument reliability in multinational health services research studies involving comparisons across health systems and language translation.

Using the Folstein Mini Mental State Exam (MMSE) to explore methodological issues in cognitive aging research

Cognitive scales are used frequently in geriatric research and practice. These instruments are constructed with underlying assumptions that are a part of their validation process. A common measurement scale used in older adults is the Folstein Mini Mental State Exam (MMSE). The MMSE was designed to screen for cognitive impairment and is used often in geriatric research. This paper has three aims. Aim one was to explore four potential threats to validity in the use of the MMSE: (1) administering the exam without meeting the underlying assumptions, (2) not reporting that the underlying assumptions were assessed prior to test administration, (3) use of variable and inconsistent cut-off scores for the determination of presence of cognitive impairment, and (4) failure to adjust the scores based on the demographic characteristics of the tested subject. Aim two was to conduct a literature search to determine if the assumptions of (1) education level assessment, (2) sensory assessment, and (3) language fluency were being met and clearly reported in published research using the MMSE. Aim three was to provide recommendations to minimalize threats to validity in research studies that use cognitive scales, such as the MMSE. We found inconsistencies in published work in reporting whether or not subjects meet the assumptions that underlie a reliable and valid MMSE score. These inconsistencies can pose threats to the reliability of exam results. Fourteen of the 50 studies reviewed reported inclusion of all three of these assumptions. Inconsistencies in reporting the inclusion of the underlying assumptions for a reliable score could mean that subjects were not appropriate to be tested by use of the MMSE or that an appropriate test administration of the MMSE was not clearly reported. Thus, the research literature could have threats to both validity and reliability based on misuse of or improper reported use of the MMSE. Six recommendations are provided to minimalize these threats in future research.

Using the Folstein Mini Mental State Exam (MMSE) to explore methodological issues in cognitive aging research

Cognitive scales are used frequently in geriatric research and practice. These instruments are constructed with underlying assumptions that are a part of their validation process. A common measurement scale used in older adults is the Folstein Mini Mental State Exam (MMSE). The MMSE was designed to screen for cognitive impairment and is used often in geriatric research. This paper has three aims. Aim one was to explore four potential threats to validity in the use of the MMSE: (1) administering the exam without meeting the underlying assumptions, (2) not reporting that the underlying assumptions were assessed prior to test administration, (3) use of variable and inconsistent cut-off scores for the determination of presence of cognitive impairment, and (4) failure to adjust the scores based on the demographic characteristics of the tested subject. Aim two was to conduct a literature search to determine if the assumptions of (1) education level assessment, (2) sensory assessment, and (3) language fluency were being met and clearly reported in published research using the MMSE. Aim three was to provide recommendations to minimalize threats to validity in research studies that use cognitive scales, such as the MMSE. We found inconsistencies in published work in reporting whether or not subjects meet the assumptions that underlie a reliable and valid MMSE score. These inconsistencies can pose threats to the reliability of exam results. Fourteen of the 50 studies reviewed reported inclusion of all three of these assumptions. Inconsistencies in reporting the inclusion of the underlying assumptions for a reliable score could mean that subjects were not appropriate to be tested by use of the MMSE or that an appropriate test administration of the MMSE was not clearly reported. Thus, the research literature could have threats to both validity and reliability based on misuse of or improper reported use of the MMSE. Six recommendations are provided to minimalize these threats in future research.

Are clinical diagnoses of Alzheimer's disease and other dementias affected by education and self-reported race?

A randomized controlled trial examined whether the diagnostic process for Alzheimer's disease and other dementias may be influenced by knowledge of the patient's education and/or self-reported race. Four conditions were implemented: diagnostic team knows (a) race and education, (b) education only, (c) race only, or (d) neither. Diagnosis and clinical staging was established at baseline, at Wave 2, and for a random sample of Wave 3 respondents by a consensus panel. At study end, a longitudinal, "gold standard" diagnosis was made for patients with follow-up data (71%). Group differences in Diagnostic and Statistical Manual of Mental Disorders (4th ed.; American Psychiatric Association, 1994) diagnosis were estimated using logistic regression and generalized estimating equations. Sensitivity and specificity were examined for baseline diagnosis in relation to the gold standard, longitudinal diagnosis. Despite equivalent status on all measured variables across waves, members of the "knows race only" group were less likely than those of other groups to receive a diagnosis of dementia. At final diagnosis, 19% of the "knows race only" group was diagnosed with dementia versus 38% to 40% in the other 3 conditions (p = .038). Examination of sensitivities and specificities of baseline diagnosis in relation to the gold standard diagnosis showed a nonsignificant trend for lower sensitivities in the knowing race conditions (0.3846), as contrasted with knowing education only (0.480) or neither (0.600). The finding that knowledge of race may influence the diagnostic process in some unknown way is timely, given the recent State-of-the-Science conference on Alzheimer's disease prevention, the authors of which called for information about and standardization of the diagnostic process.

Explaining differences in episodic memory performance among older African Americans and Whites: the roles of factors related to cognitive reserve and test bias

Older African Americans tend to perform poorly in comparison with older Whites on episodic memory tests. Observed group differences may reflect some combination of biological differences, measurement bias, and other confounding factors that differ across groups. Cognitive reserve refers to the hypothesis that factors, such as years of education, cognitive activity, and socioeconomic status, promote brain resilience in the face of pathological threats to brain integrity in late life. Educational quality, measured by reading test performance, has been postulated as an important aspect of cognitive reserve. Previous studies have not concurrently evaluated test bias and other explanations for observed differences between older African Americans and Whites. We combined data from two studies to address this question. We analyzed data from 273 African American and 720 White older adults. We assessed DIF using an item response theory/ordinal logistic regression approach. DIF and factors associated with cognitive reserve did not explain the relationship between race, and age- and sex-adjusted episodic memory test performance. However, reading level did explain this relationship. The results reinforce the importance of considering education quality, as measured by reading level, when assessing cognition among diverse older adults.

Operationalizing diagnostic criteria for Alzheimer's disease and other age-related cognitive impairment-Part 1

In this article, the challenges faced by several noted population studies for Alzheimer dementia in operationalizing current clinical diagnostic criteria for Alzheimer's disease (AD) have been reviewed. Differences in case ascertainment, methodological biases, cultural and educational influences on test performance, inclusion of special populations such as underrepresented minorities and the oldest old, and detection of the earliest symptomatic stages of underlying AD have been considered. Classification of Alzheimer dementia may be improved by the incorporation of biomarkers for AD if the sensitivity, specificity, and predictive value of the biomarkers are established and if they are appropriate for epidemiological studies, as may occur should a plasma biomarker be developed. Biomarkers for AD could also facilitate studies of the interactions of various forms of neurodegenerative disorders with cerebrovascular disease, resulting in "mixed dementia".

The relationship between education level and mini-mental state examination domains among older Mexican Americans

To study the effect of education and language of response at the interview on performance in the Mini-Mental State Examination (MMSE) domains, we studied 2861 Mexican Americans aged 65 and older from the Hispanic Established Populations for Epidemiologic Studies of the Elderly (EPESE) followed from 1993 to 1994 until 2004 to 2005. The MMSE was examined as total score (0-30) or divided into 2 global domains: (1) no-memory (score 0-24): Orientation, attention, and language; and (2) memory (score 0-6): working and delayed memory. Mean age and total MMSE were 72.7 years and 24.6 at baseline, and 81.7 years and 20.5 at 11 years of follow-up. Spanish-speaking participants had less education (4.1 vs 7.4 years, P < .0001), they had significantly higher adjusted mean scores for memory, no-memory, and total MMSE compared with English-speaking participants. In multivariate longitudinal analyses, participants with more years of education performed better than those with less education, especially in total MMSE and no-memory domain. Spanish-speaking participants with 4 to 6 years of education had higher memory scores than those speaking English (estimate 0.40, standard error [SE] = 0.14, P < .001), 7 to 11 (estimate 0.27, standard error = 0.13, P < .01) or 12+ (estimate 0.44, standard error = 0.13, P < .001). Results suggest that cultural factors and variables related to preferred language use determined variations in MMSE performance. Because the memory domain of the MMSE is less affected by education, it may be used along with other cognitive tests for early detection of cognitive decline in older populations with low education.

Interpretation of differential item functioning analyses using external review

Differential item functioning (DIF) analyses are used to determine whether certain groups respond differently to a particular item of a test or questionnaire; however, these do not explain the reasons for observed response differences. Many studies have used external reviews of items, sometimes using blinded reviewers, to help interpret these results. The authors conducted a literature review of this topic to describe the current usage of external reviews alongside DIF analyses. It concentrated on studies of health-related quality of life instruments, but studies in other fields were also considered. Relatively few examples of blinded item reviews were identified, and these were mostly from educational studies. A case study using blinded bilingual reviewers alongside translation DIF analyses of a health-related quality of life instrument is described. Future researchers should consider conducting external item reviews alongside DIF analyses.

Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression

BACKGROUND

Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application.

METHODS

A review of logistic regression DIF analyses in HRQoL was undertaken. Methodological articles from other fields and using other DIF methods were also included if considered relevant.

RESULTS

There are many competing approaches for the conduct of DIF analyses and many criteria for determining what constitutes significant DIF. DIF in short scales, as commonly found in HRQL instruments, may be more difficult to interpret. Qualitative methods may aid interpretation of such DIF analyses.

CONCLUSIONS

A number of methodological choices must be made when applying logistic regression for DIF analyses, and many of these affect the results. We provide recommendations based on reviewing the current evidence. Although the focus is on logistic regression, many of our results should be applicable to DIF analyses in general. There is a need for more empirical and theoretical work in this area.

Partial measurement equivalence of French and English versions of the Canadian Study of Health and Aging neuropsychological battery

Neuropsychological batteries are often translated for use across populations differing in preferred language. Yet, equivalence in construct measurement across groups cannot be assumed. To address this issue, we examined data from the Canadian Study of Health and Aging, a large study of older adults. We tested the hypothesis that the latent variables underlying the neuropsychological battery administered in French or English were the same (invariant). The best-fitting baseline model, established in the English-speaking Exploratory sample (n = 716), replicated well in the English-speaking Validation sample (n = 715), and the French-speaking sample (FS, n = 446). Across the English- and FSs, two of the factors, Long-term Retrieval and Visuospatial speed, displayed invariance, that is, reflected the same constructs measured in the same scales. In contrast, the Verbal Ability factor showed only partial invariance, reflecting differences in the relative difficulty of some tests of language functions. This empirical demonstration of partial measurement invariance lends support to the continued use of these translated measures in clinical and research contexts and illustrates a framework for detailed evaluation of the generality of models of cognition and psychopathology, across groups of any sort.

Cross-cultural comparisons of the Mini-mental State Examination between Japanese and U.S. cohorts

BACKGROUND

The Mini-mental State Examination (MMSE) is widely used in Japan and the U.S.A. for cognitive screening in the clinical setting and in epidemiological studies. A previous Japanese community study reported distributions of the MMSE total score very similar to that of the U.S.A.

METHODS

Data were obtained from the Monongahela Valley Independent Elder's Study (MoVIES), a representative sample of community-dwelling elderly people aged 65 and older living near Pittsburgh, U.S.A., and from the Tajiri Project, with similar aims in Tajiri, Japan. We examined item-by-item distributions of the MMSE between two cohorts, comparing (1) percentage of correct answers for each item within each cohort, and (2) relative difficulty of each item measured by Item Characteristic Curve analysis (ICC), which estimates log odds of obtaining a correct answer adjusted for the remaining MMSE items, demographic variables (age, gender, education) and interactions of demographic variables and cohort.

RESULTS

Median MMSE scores were very similar between the two samples within the same education groups. However, the relative difficulty of each item differed substantially between the two cohorts. Specifically, recall and auditory comprehension were easier for the Tajiri group, but reading comprehension and sentence construction were easier for the MoVIES group.

CONCLUSIONS

Our results reaffirm the importance of validation and examination of thresholds in each cohort to be studied when a common instrument is used as a dementia screening tool or for defining cognitive impairment.

Are comparisons the answer to understanding behavioral aspects of aging in racial and ethnic groups?

The knowledge gained from studying diverse populations should help to address inequities and prepare us to deal with the needs of the increasing number of older minorities in this country. At the same time, research that is not properly conducted threatens to lead us astray and misconstrue relationships and outcomes related to behavioral aspects of aging. In this article, we propose that simple comparisons between groups are neither necessary nor sufficient to advance our understanding of ethnic minorities. We discuss common pitfalls conducted in group-differences research, including a specific treatment on the issue of statistical power issues. Our goal is to encourage the use of multiple methodological designs in the study of issues related to racial and ethnic minorities by demonstrating some of the advantages of lesser employed approaches.