Confirmatory factor analysis of the Wechsler Memory Scale-Revised in a sample of clients with alcohol dependency

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.

Confirmatory factor analysis of the behavioral dyscontrol scale in a mixed clinical sample

The Behavioral Dyscontrol Scale (BDS) is a brief measure of executive functioning originally designed for use primarily with older adults. Previous research suggests that factors derived from exploratory factor analysis of the BDS have clinical utility and are theoretically meaningful; however, the factor structure has not been previously submitted to confirmatory analysis, and there are several potential methodological problems with the previous exploratory factor analysis. In this study, we conducted a confirmatory factor analysis of the BDS. Findings were largely consistent with the original exploratory analysis (Grigsby, Kaye, & Robbins, 1992) in suggesting a three-factor model, although the three-factor model was a better fit if factors were allowed to correlate with one another. The findings of this study lend support to the current practice of using factor scores in clinical and research applications.

Factor analysis of asthma and atopy traits shows 2 major components, one of which is linked to markers on chromosome 5q

BACKGROUND

A variety of definitions of asthma and atopy traits have been used in genetic studies. The variables used may be correlated, increasing the likelihood of type I error.

OBJECTIVE

We sought to clarify and quantify phenotypes that may be characterized by related traits. Principal components and factor analysis were applied to the correlation matrix of asthma and atopy traits before linkage analysis.

METHODS

Factor analysis was performed on 468 Hispanic and non-Hispanic white children enrolled in the Tucson Children's Respiratory Study, with complete information on 24 items, including skin test response to 7 allergens, total serum IgE levels, presence or absence of asthma attacks, wheezing episodes, hay fever, and cough. Factor score coefficients were then applied to all siblings (n = 877), and quantitative factor scores were derived. Single-point and multipoint nonparametric sib-pair analyses were performed to assess linkage to markers on chromosome 5q31-33. Analyses were also performed for individual items.

RESULTS

Two main factors were identified: Factor I had high loadings on atopic items, including skin test responses, IgE, and hay fever, and Factor II had high loadings that included asthma diagnosis, wheezing, cough, and Alternaria species skin test response. Factors I and II were correlated at an r value of 0.19. For the quantitative factor scores, significant single-point linkage (P < .0001) was demonstrated only for atopic Factor I, and a peak multipoint LOD score of 2.7 was seen for marker D5S479. Multipoint LOD scores for individual items were 1.1 or less.

CONCLUSION

These analyses suggest evidence for a locus or loci mapping to chromosome 5q31-33 associated with this composite atopic phenotype.