Biomedical subjects

Steven P Reise

Publications and source records attributed to Steven P Reise.

8 recordsLinked to original sources

PubMed2005

Stability and clinical correlates of personality characteristics in recent-onset schizophrenia.

BACKGROUND: While several personality characteristics are implicated in the etiology and phenotypic expression of schizophrenia, little is known about their trait status or clinical correlates during the early course of this disorder. METHOD: The stability of five personality characteristics derived from the MMPI-168 was examined in recent-onset schizophrenia patients (n = 59) during a psychotic period at study entry and at two out-patient assessments over the following 15 months and in non-patient controls (n = 39) at similar time intervals. Among patients, associations between personality characteristics and clinical symptoms and exposure to stressful life events during the study period were also examined. RESULTS: Multilevel modeling analyses indicated that the between-subjects or trait-like variance components for these characteristics among patients were substantial, albeit smaller than those found for controls. Patients reported higher mean levels of Neuroticism, Cynicism, and Psychotic Ideation and lower mean levels of Psychopathic Tendencies and Denial of Somatic Complaints than controls. Among patients, several personality characteristics were systematically related to mean clinical symptom levels as well as frequency of exposure to dependent, but not independent, life events. CONCLUSIONS: Stable individual differences in personality are detectable during the early course of schizophrenia and may help account for heterogeneity in clinical symptoms and functional outcome.

Adult↗

PubMed2005

An illustration of multilevel factor analysis.

The factor analysis of repeated measures psychiatric data presents interesting challenges for researchers in terms of identifying the latent structure of an assessment instrument. Specifically, repeated measures contain both within and between individual sources of variance. Although a number of techniques exist for separating out these 2 sources of variance, all are problematic. Recently, researchers have proposed that exploratory multilevel factor analysis (MFA) be used to appropriately analyze the latent structure of repeated measures data. The chief objective of this report is to provide a didactic step-by-step guide on how MFA may be applied to psychiatric data. In the discussion, we describe difficulties associated with MFA and consider challenges in factor analyzing life event appraisals in psychiatric samples.

Adolescent↗

PubMed2005

Item response theory and the measurement of clinical change.

An instrument's sensitivity to detect individual-level change is an important consideration for both psychometric and clinical researchers. In this article, we develop a cognitive problems measure and evaluate its sensitivity to detect change from an item response theory (IRT) perspective. After illustrating assumption checking and model fit assessment, we detail 4 features of IRT modeling: (a) the scale information curve and its relation to the bandwidth of measurement precision, (b) the scale response curve and how it is used to link the latent trait metric with the raw score metric, (c) content-based versus norm-based score referencing, and (d) the level of measurement of the latent trait scale. We conclude that IRT offers an informative, alternative framework for understanding an instrument's psychometric properties and recommend that IRT analyses be considered prior to investigations of change, growth, or the effectiveness of clinical interventions.

Adult↗

PubMed2004

Three Mahalanobis distances and their role in assessing unidimensionality.

Unidimensionality is the hallmark psychometric feature of a well-constructed measurement scale. However, in determining the degree to which a set of items form a unidimensional scale, aberrant item response patterns may distort our investigations. For example, aberrant response patterns may adversely impact interitem covariances which, in turn, can distort estimates of a scale's dimensionality and reliability. In this study, we investigate and compare the utility of three Mahalanobis distance (M-distance) measures in identifying and downweighting aberrant item response patterns. Our findings indicated that a residual-based M-distance measure had the best properties. Specifically, response patterns having greater residual-based M-distances were responsible for observed violations of unidimensionality. When these response patterns were properly downweighted according to this M-distance, the data fitted a one-factor model better and scale reliability increased. The procedures are illustrated using three real data sets.

Humans↗

PubMed2003

Do health care ratings differ by race or ethnicity?

BACKGROUND: There is growing evidence that Asians and Pacific Islanders perceive their health care more negatively than whites and other racial and ethnic subgroups. This study of differences in health care experiences by race and ethnicity was the first to use nationally representative data. METHODS: Data from the 1998 National Research Corporation Healthcare Market Guide survey were analyzed. A total of 120,855 respondents were included in the study. Four global satisfaction ratings (overall health plan satisfaction, medical care satisfaction, recommend plan to others, and intent to switch plans) and four composite measures (access to care, providers' delivery of care, customer service, and cost/benefits of care) were examined. RESULTS: Nonwhite survey respondents--particularly those in the other/multiracial and Asian/Pacific Islander groups--rated their health plan coverage and medical care lower than whites. DISCUSSION: The results of this study are consistent with those of other recent (and comparable) studies in which these racial and ethnic groups are represented. Most strikingly consistent, however, are the lower ratings of Asians/Pacific Islanders and the comparable (and higher) ratings (compared to whites) of African Americans. Why Asians/Pacific Islanders are considerably less satisfied with their medical care than all other racial and ethnic groups in the United States needs to be explored. Access to care and quality of care improvement efforts should be directed at all ethnic minority groups, particularly for limited English-speaking, other/multiracial, Hispanic, and Asian/Pacific Islander subgroups.

Adolescent↗

PubMed2003

How many IRT parameters does it take to model psychopathology items?

The authors compared the fit of the 2- and 3-parameter logistic models (2PLM; 3PLM) on 15 unidimensional factor scales derived from the Minnesota Multiphasic Personality Inventory--Adolescent item pool. Log-likelihood chi-square deviance tests indicated that a 3PLM provided an improved fit. However, residual statistics indicated that the difference in fit between the 2 models was negligible. An unexpected finding was that from 10% to 30% of the items had substantial lower asymptote parameters (c > or = .10) when the scales were scored in the pathology or nonpathology directions. The authors argue that the large lower asymptote parameters are attributable to item-content ambiguity possibly caused by item-level multidimensionality. These findings suggest that the direction of scoring can critically affect an item response theory analysis.

Adolescent↗

PubMed2003

A discussion of modern versus traditional psychometrics as applied to personality assessment scales.

Item response theory (IRT) methods are used by large testing firms, state agencies, and school districts to construct, analyze, and score most major aptitude, achievement, proficiency, entrance, and professional licensure exams. Personality assessment, in contrast, has not generally adopted these more powerful, modern psychometric techniques. We evaluate the possible role of IRT in the personality domain by highlighting key areas in which IRT and traditional methods differ. Although we conclude that IRT has a significant role to play in future personality measurement, there are many systemic and technical barriers to its routine application.

Forecasting↗

PubMed1993

Confirmatory factor analysis and item response theory: two approaches for exploring measurement invariance.

This study investigated the utility of confirmatory factor analysis (CFA) and item response theory (IRT) models for testing the comparability of psychological measurements. Both procedures were used to investigate whether mood ratings collected in Minnesota and China were comparable. Several issues were addressed. The first issue was that of establishing a common measurement scale across groups, which involves full or partial measurement invariance of trait indicators. It is shown that using CFA or IRT models, test items that function differentially as trait indicators across groups need not interfere with comparing examinees on the same trait dimension. Second, the issue of model fit was addressed. It is proposed that person-fit statistics be used to judge the practical fit of IRT models. Finally, topics for future research are suggested.

Adult↗