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C Hertzog

Publications and source records attributed to C Hertzog.

43 records · Page 3Linked to original sources
PubMed1986

Age-related slowing in semantic information processing speed: an individual differences analysis.

This study investigated age differences in the speed of processing semantic information. Thirty young adults and 25 older adults completed five reaction time (RT) tasks: simple RT, two-choice RT to nonverbal stimuli, and three tasks measuring speed of making semantic judgments. The data were used to examine individual differences in RT factors, estimated by means of confirmatory factor analysis. All three semantic RT tasks loaded on a single semantic RT factor, with equivalent factor loadings for young and older participants, indicating that the three tasks were measuring a common factor of semantic memory access speed (SMA). The two groups differed significantly in the covariances among the RT factors; most important, the SMA factor had a higher correlation with a two-choice RT factor in the older group. This finding is taken as support of individual differences in age-related slowing on these two RT factors.

Adult↗
PubMed1985

Repeated-measures analysis of variance in developmental research: selected issues.

This paper presents a review of recent developments in statistical techniques for repeated-measures analysis of variance. Since the literature has emphasized the issue of mixed model assumptions and their violation, we present an updated perspective on the nature of these assumptions and their implications for mixed model, adjusted mixed model, or multivariate significance tests. However, the central theme of the review is that the validity of mixed model assumptions is but one consideration in selection of an appropriate method of repeated-measures ANOVA. In particular, we recommend the avoidance of omnibus significance tests in favor of specific planned comparisons whenever hypotheses more specific than the omnibus null hypothesis may be formulated a priori. The analyst must also consider whether multiple dependent measures are to be analyzed, and the paper discusses alternative approaches to true multivariate repeated-measures designs. It also includes discussion of other relevant issues, including a brief review of the strengths and weaknesses of commonly available statistical software when applied to the analysis of repeated-measures data.

Analysis of Variance↗
PubMed1982

[High frequency ventilation by the inter-cricothyroid approach during ENT endoscopy: report on 83 cases (author's transl)].

The value of high frequency ventilation employing the inter-cricothyroid approach was assessed during general anesthesia for endoscopic examination of the upper respiratory tract passages. The technique for introducing the inter-cricothyroid canula, and the ventilatory apparatus, are described, and results exposed as a function of local effects of puncture and the quality of pulmonary ventilation obtained. Advantages, and other indications for the use of this technique, are discussed.

Adult↗
PubMed1978

Cardiovascular disease and changes in intellectual functioning from middle to old age.

The relationship between cardiovascular disease (CVD) and intellectual functioning was investigated using a categorical division of a previously studied cross-sequential sample into groups with and without clinical cardiovascular diagnoses during the period of assessment. CVD was found to be a significant predictor of performance on several cognitive subtests, even when chronological age (cohort) was included as a factor in the statistical analysis. However, the pattern of effects was not completely consistent with a model relating CVD to intellectual decrement over time. Further breakdown of subjects into CVD subgroups (e.g., hypertension) showed the CVD effect to be specific to some subgroups, but did not fully resolve the inconsistency with the decremental model. The results also suggest CVD to be one of the factors leading to subsequent attrition from the sequential sample.

Aged↗
PubMedDate not supplied

On the differentiation of memory beliefs from memory knowledge: the factor structure of the Metamemory in Adulthood Scale.

This study was designed to test the hypothesis that there are multiple factors of metamemory present in the Metamemory in Adulthood (MIA) questionnaire. Data on seven MIA scales from six separate studies on memory/metamemory relationships (total N = 750) were combined to yield two half-samples for cross-validation purposes. The samples were partitioned into young, middle-aged, and old groups. A multiple group confirmatory factor analysis was then conducted on the data, using the first half sample to develop a model and the second half sample to validate it. Although the models did not fully cross-validate, both analyses indicated that there are at least two higher-order factors in the MIA. The first involves beliefs about self-efficacy in using memory. The second factor combines knowledge about memory and affect concerning memory (e.g., achievement motivation). The analyses also indicated that the factor loadings for the second factor, tentatively labelled Knowledge, were invariant across the three age groups, but that there were age differences in the Self-Efficacy Beliefs factor loadings. The differences were localized to age-related increases in the loadings for the MIA Change and Locus scales. The two factor solution has potential for resolving conflicting results in the literature regarding age differences in both metamemory and metamemory/memory performance relationships.

Adult↗