Biomedical subjects

Akihito Kamata

Publications and source records attributed to Akihito Kamata.

5 recordsLinked to original sources

PubMed2005

Modeling treatment motivation in substance-abusing women with children.

OBJECTIVES: Children are often considered a primary motivator for women seeking substance abuse treatment. This study tested a model predicting treatment motivation in substance-abusing mothers. METHODS: This study was a secondary analysis of the Drug Absue Treatment Outcome Study (DATOS). It used structural equation modeling to describe factors influencing motivation for treatment. DATOS is a national study of substance abusers entering treatment. Treatment was provided by a sampling of community-based programs, free-standing hospitals, hospital units, county-funded programs, modified therapeutic communities, and criminal justice programs. The subsample of women with children under the age of 18 for whom custody of children could be determined was selected (n=1371). The variables comprising each factor were based on self-report, and standardized scales measuring level of drug involvement, psychological functioning, children, and a desire to stop using drugs were used. RESULTS: Drug involvement was positively related to poorer psychological functioning, child custody issues, and the desire to stop using drugs. Child custody issues had a negative influence, while poorer psychological functioning and a desire to stop using drugs positively influenced treatment motivation. CONCLUSIONS: The negative influence that children have on treatment motivation may reflect the practical or emotional difficulties of having to leave children behind or in some instances having children placed in foster care. Specifically, losing custody of children, particularly with little expectation they will be reunified, may serve as a detriment to motivation. Popular beliefs hold that children serve as a primary source of a mother's treatment motivation; however this study found the opposite was true. Children should not automatically be considered a primary source of motivation for participation in treatment.

Adolescent↗

PubMed2005

The multilevel measurement model: introduction to the special issue.

An introduction to the special issue on the multilevel measurement model (MMM) is provided. The two- and three-level multilevel models for continuous outcomes are reviewed. The extension to the hierarchical generalized linear model and its use as a multilevel measurement model for dichotomous measurement indicators is demonstrated. The six articles in the special issue are described.

Humans↗

PubMed2005

Modeling local item dependence with the hierarchical generalized linear model.

Local item dependence (LID) can emerge when the test items are nested within common stimuli or item groups. This study proposes a three-level hierarchical generalized linear model (HGLM) to model LID when LID is due to such contextual effects. The proposed three-level HGLM was examined by analyzing simulated data sets and was compared with the Rasch-equivalent two-level HGLM that ignores such a nested structure of test items. The results demonstrated that the proposed model could capture LID and estimate its magnitude. Also, the two-level HGLM resulted in larger mean absolute differences between the true and the estimated item difficulties than those from the proposed three-level HGLM. Furthermore, it was demonstrated that the proposed three-level HGLM estimated the ability distribution variance unaffected by the LID magnitude, while the two-level HGLM with no LID consideration increasingly underestimated the ability variance as the LID magnitude increased.

Data Interpretation, Statistical↗

PubMed2005

Test equating in the presence of DIF items.

This paper proposes a multilevel measurement model that controls for DIF effects in test equating. The accuracy and stability of item and ability parameter estimates under the proposed multilevel measurement model were examined using randomly simulated data. Estimates from the proposed model were compared with those resulting from two multiple-group concurrent equating designs, including 1) a design that replaced DIF-items with items with no DIF; and 2) a design that retained DIF items with no attempt to control for DIF. In most of the investigated conditions, the results indicated that the proposed multilevel measurement model performed better than the two comparison models.

Educational Measurement↗

PubMed2003

College women with eating disorders: self-regulation, life satisfaction, and positive/negative affect.

The authors examined the self-regulatory strategies and subjective well-being of students recently diagnosed with eating disorders, at-risk students, and individuals without eating disorders. Fifty-six college students were individually interviewed regarding their use of self-regulatory strategies to lose and maintain their weight; they also completed the Extended Satisfaction with Life Scale (V. C. Alfonzo, D. B. Allison, D. E. Rader, & B. S. Gorman, 1996) and the Positive and Negative Affect Scale (D. Watson, L. A. Clarck, & A. Tellegen, 1988). As hypothesized, students with eating disorders reported more self-regulated strategies for managing their weight, a lower level of life satisfaction, and higher levels of negative affect than did at-risk students or individuals with normal weights. At-risk students reported higher levels of self-regulation and negative affect than did the students with normal weights. These findings may be useful for parents and health practitioners providing care to college students, who must be made aware of the signs and symptoms of these disorders.

Adult↗