PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 1459164

Component analysis in multivariate aging research.

R E Millsap·W Meredith
View original source ↗Export metadata ↓

Abstract

A method of components analysis, related to principal components analysis, is described for applications in multivariate cross-sectional or longitudinal data. The method may be useful to researchers seeking to reduce the number of observed variables through scale construction. The method creates component variables as weighted sums of the observed variables using weights that are identical across groups and occasions. The statistical and conceptual properties of these components are discussed. The method is contrasted with traditional principal components analysis and factor analysis. An application of the method is presented using longitudinal WAIS and WAIS-R data.

Explore related subjects

Cross-Sectional StudiesFactor Analysis, StatisticalGeriatricsHumansLongitudinal StudiesMultivariate AnalysisWechsler ScalesJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R E Millsap, W Meredith. Component analysis in multivariate aging research.. https://doi.org/10.1080/03610739208260359

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Human pegivirus 1 in healthy blood donors and in acute febrile patients from Mato Grosso, Midwestern Brazil.

The association between Human Pegivirus 1 (HPgV-1, Pegivirus hominis, family Hepaciviridae) with disease etiology remains unclear, yet this virus is widely distributed among people exposed to contaminated blood. This study aimed to identify the prevalence and characterize HPgV-1 genomes obtained from acute febrile patients (n = 92 from 2019) and from blood donors (n = 633 from 2022) sampled in Mato Grosso, Brazil. The serum samples were tested by RT-qPCR for a conserved 5' UTR region of HPgV-1. Nucleic acid of 28 positive samples was converted to ds-cDNA, purified and sequenced with an Illumina NextSeq platform. The prevalence of HPgV-1 among acute febrile patients was 4.35% (4/92), who were mostly female (3/4; 75.00%) mean 28.86 (12-67) years-old; whereas among blood donors it was 3.79% (24/633), which were predominantly male (16/24; 66.67%), aged 30-45 years-old (13/24; 54.17%). Eight HPgV-1 genomic sequences (7,708-9,248) were recovered; two belong to subgenotype 2a and clustered with strains from United States, Brazil, France and Japan, while the remaining six genomes from subgenotype 2b grouped with strains from Pará, Brazil and abroad. HPgV-1 detection in acute febrile patients and in healthy blood donors highlights the necessity to investigate the epidemiological aspects of this infection, as well as the possible impact to public health in Midwestern Brazil.

Cross-Sectional Studies↗
PubMed2026

A cross-sectional study of oxidative stress pathway genotypes and their interactions with environmental pollutant levels identifies associations with gene expression and lung function.

BACKGROUND: Asthma is a heterogeneous disease influenced by genetic and environmental factors. Fine particulate matter (PM2.5) exacerbates asthma, likely through oxidative stress pathways, but whether genetic variation modifies this effect remains unclear. METHODS: We analysed data on 948 adults with asthma from the Severe Asthma Research Program (SARP), linking ZIP-code-level PM2.5 exposure with whole-genome sequencing data. We tested 4337 single nucleotide polymorphisms (SNPs) in 120 oxidative stress pathway genes for gene-environment (GxE) interactions with PM2.5 on lung function (forced expiratory volume in 1 s [FEV1] % predicted) using weighted linear regression. Gene expression data from bronchial epithelial cells (n = 170) were used to assess cis-expression quantitative trait loci (eQTLs). FINDINGS: Higher PM2.5 exposure was associated with lower FEV1% predicted (β per μg/m3 = -0.7, p = 0.01). We identified 20 SNPs across seven genes (OXSR1, PXDN, TPO, LRRK2, APP, MSRA, MSRB2) with significant GxE interactions after multiple-testing correction. Five SNPs were also eQTLs, linking PM2.5-modified gene expression to lung function. Minor alleles in OXSR1 and PXDN were associated with reduced gene expression and worsened FEV1% under high PM2.5 exposure. Conversely, TPO variants were associated with higher baseline expression and lower lung function, but under increasing PM2.5 exposure, minor allele carriers showed suppressed TPO expression and improved FEV1%. INTERPRETATION: This study identified 20 SNPs in oxidative stress pathway genes that modify the effect of PM2.5 on lung function in asthma. These findings highlight the importance of integrating environmental context in genetic studies and suggest potential therapeutic targets for pollution-sensitive asthma phenotypes. FUNDING: Supported by NIH grants.

Cross-Sectional Studies↗
PubMed1992

[Value of laboratory diagnosis of liver function from the insurance medicine viewpoint].

After a brief passage on the reliability and special features of the most important liver values, this paper deals with the diseases of the liver most frequent in everyday rating practice from the angle of specific laboratory patterns and enzyme processes, putting emphasis on prognostic aspects. Special mention is made of the most recent diagnostic findings in the field of virus hepatitis. Furthermore, the influence of alcohol on the liver values is explained in detail. In a résumé, GPT, Gamma-GT and cholinesterase are regarded as sufficient for classifying almost 98% of all diseases of the liver, the limited significance of liver values as "functional parameters" being stressed, however.

Cross-Sectional Studies↗