Biomedical subjects

Lance Jolley

Publications and source records attributed to Lance Jolley.

5 recordsLinked to original sources

PubMed2006

Differential item functioning related to education and age in the Italian version of the Mini-mental State Examination.

BACKGROUND: Differential item functioning (DIF) exists when test item responses by members of different demographic groups are statistically different when controlling for ability. DIF may indicate item bias. Our objective was to determine whether items from the Italian Mini-mental State Examination (MMSE) had DIF related to educational attainment, age, gender and occupation. We were also interested in exploring the significance of DIF in screening tests. METHODS: In a two-stage study from Granarolo, Italy, residents over age 61 (n = 495) were evaluated with the Italian MMSE. Those with MMSE scores of 28 or lower were further evaluated for dementia. MMSE results were coded in 10 item bundles. We used ordinal logistic regression to determine whether item bundles had DIF. RESULTS: Six of the 10 MMSE item bundles had DIF in educational attainment subgroups. Four of these six bundles also had DIF related to age. Items that required literacy were much harder for those with lower educational attainment. CONCLUSIONS: DIF related to education appeared at as few as 3 years of formal schooling. These findings suggest cautious interpretation of data from studies using the Italian MMSE in populations with heterogeneous educational backgrounds. DIF is especially troublesome for two-stage studies that use screening tests.

Aged↗

PubMed2006

Differential item functioning analysis with ordinal logistic regression techniques. DIFdetect and difwithpar.

INTRODUCTION: We present an ordinal logistic regression model for identification of items with differential item functioning (DIF) and apply this model to a Mini-Mental State Examination (MMSE) dataset. We employ item response theory ability estimation in our models. Three nested ordinal logistic regression models are applied to each item. Model testing begins with examination of the statistical significance of the interaction term between ability and the group indicator, consistent with nonuniform DIF. Then we turn our attention to the coefficient of the ability term in models with and without the group term. If including the group term has a marked effect on that coefficient, we declare that it has uniform DIF. We examined DIF related to language of test administration in addition to self-reported race, Hispanic ethnicity, age, years of education, and sex. METHODS: We used PARSCALE for IRT analyses and STATA for ordinal logistic regression approaches. We used an iterative technique for adjusting IRT ability estimates on the basis of DIF findings. RESULTS: Five items were found to have DIF related to language. These same items also had DIF related to other covariates. DISCUSSION: The ordinal logistic regression approach to DIF detection, when combined with IRT ability estimates, provides a reasonable alternative for DIF detection. There appear to be several items with significant DIF related to language of test administration in the MMSE. More attention needs to be paid to the specific criteria used to determine whether an item has DIF, not just the technique used to identify DIF.

Bias↗

PubMed2005

Education modifies the effect of apolipoprotein epsilon 4 on cognitive decline.

OBJECTIVES: To assess the influence of education on the association between apolipoprotein E and cognitive change. DESIGN: Prospective cohort. PARTICIPANTS: HMO-based sample of 2168 non-demented community-dwelling elderly followed over 6 years. MEASUREMENTS: Generalized estimating equations were used with the difference between baseline and follow-up cognitive abilities screening instrument (CASI) as the outcome variable. RESULTS: At follow-up, 6% of the sample had a decline of 1.5 S.D. or greater on the CASI. Compared to individuals without an APOE4 allele, individuals with a single APOE4 allele did not have greater CASI decline. By contrast, individuals with two APOE4 alleles experienced greater decline in cognitive performance and the magnitude of that decline decreased as years of educational attainment increased. These relationships held after adjusting for age, gender, ethnicity, depression, diabetes, and history of vascular disease. CONCLUSION: Lower education was associated with steep 4-year cognitive decline for APOE4 homozygotes but not for APOE4 heterozygotes. Potentially modifiable host factors such as education could influence the association of high-risk genotypes and cognitive decline.

Age Factors↗

PubMed2002

Dementia and Alzheimer disease incidence: a prospective cohort study.

CONTEXT: Age-specific incidence rates for dementia and Alzheimer disease (AD) are important for research and clinical practice. Incidence estimates for the United States are few and vary with the population sampled and study design; we present data that will contribute to a consensus of these rates. OBJECTIVES: To provide age-specific incidence estimates for dementia and AD and to estimate the association of sex, educational level, and apolipoprotein E genotype with onset. DESIGN: Prospective cohort study; begun in 1994 with follow-up interviews every 2 years. SETTING: Members of community-based, large health maintenance organization with demographics consistent with the surrounding base population; diagnostic evaluation by university-based study clinicians. SUBJECTS: Random sample of subjects aged 65 years or older from the base population; dementia free, nonnursing home residents. Of 5422 who were eligible, 2581 were enrolled, and 2356 had at least 1 follow-up evaluation (10 591 person-years of observation). MAIN OUTCOME MEASURE: Dementia and Alzheimer disease diagnoses were based on standard criteria. Age-specific incidence rates were calculated using a person-years approach with Poisson distribution confidence intervals. Cox proportional hazards model analysis was used to examine other factors. RESULTS: Two hundred fifteen cases of dementia and 151 cases of AD were diagnosed. Incidence rates for dementia and AD increase across the 5-year age groups; AD rates rise from 2.8 per 1000 person-years (age group, 65-69 years) to 56.1 per 1000 person-years in the older than 90-year age group. The rates nearly triple from the 75-to-79-year and 80-to-84-year age groups, but the relative increase is much less thereafter. Sex was not associated with AD onset. Educational level (>15 years vs <12 years) was associated with a decreased risk of AD; however, the association was also dependent on the baseline cognitive screening test score. CONCLUSIONS: Our dementia and AD incidence rates are consistent with recent US and European cohort studies, providing clinicians and researchers new information concerning the reproducibility of incidence estimates across settings. Increased risk was associated with age and the apolipoprotein E genotype; also with a low baseline cognitive screening test score. Educational level was inversely associated with the risk of dementia and positively associated with the baseline cognitive test score; thus, detection of AD by the screening test could also be influenced by educational level.

Age Factors↗

PubMed2002

Temporal association of children's pesticide exposure and agricultural spraying: report of a longitudinal biological monitoring study.

We measured organophosphorus (OP) pesticide exposures of young children living in an agricultural community over an entire year and evaluated the impact of agricultural spraying on exposure. We also examined the roles of age, sex, parental occupation, and residential proximity to fields. We recruited 44 children (2-5 years old) through a Women, Infants, and Children clinic. We collected urine samples on a biweekly basis over a 21-month period. Each child provided at least 16 urine samples, and most provided 26. We analyzed samples for the dialkylphosphate (DAP) metabolites common to the OP pesticides. DAP concentrations were elevated in months when OP pesticides were sprayed in the region's orchards. The geometric means of dimethyl and diethyl DAPs during spray months were higher than those during nonspray months (p = 0.009 for dimethyl; p = 0.018 for diethyl). Dimethyl DAP geometric means were 0.1 and 0.07 micro mol/L for spray months and nonspray months, respectively (57% difference); diethyl DAP geometric means were 0.49 and 0.35, respectively (40% difference). We also observed differences for sex of the child, with male levels higher than female levels (p = 0.005 for dimethyl; p = 0.046 for diethyl). We observed no differences due to age, parental occupation, or residential proximity to fields. This study reports for the first time the temporal pattern of pesticide exposures over the course of a full year and indicates that pesticide spraying in an agricultural region can increase children's exposure in the absence of parental work contact with pesticides or residential proximity to pesticide-treated farmland.

Agriculture↗