792 resultados para Confirmatory Factor-analysis
Resumo:
Dealing with latent constructs (loaded by reflective and congeneric measures) cross-culturally compared means studying how these unobserved variables vary, and/or covary each other, after controlling for possibly disturbing cultural forces. This yields to the so-called ‘measurement invariance’ matter that refers to the extent to which data collected by the same multi-item measurement instrument (i.e., self-reported questionnaire of items underlying common latent constructs) are comparable across different cultural environments. As a matter of fact, it would be unthinkable exploring latent variables heterogeneity (e.g., latent means; latent levels of deviations from the means (i.e., latent variances), latent levels of shared variation from the respective means (i.e., latent covariances), levels of magnitude of structural path coefficients with regard to causal relations among latent variables) across different populations without controlling for cultural bias in the underlying measures. Furthermore, it would be unrealistic to assess this latter correction without using a framework that is able to take into account all these potential cultural biases across populations simultaneously. Since the real world ‘acts’ in a simultaneous way as well. As a consequence, I, as researcher, may want to control for cultural forces hypothesizing they are all acting at the same time throughout groups of comparison and therefore examining if they are inflating or suppressing my new estimations with hierarchical nested constraints on the original estimated parameters. Multi Sample Structural Equation Modeling-based Confirmatory Factor Analysis (MS-SEM-based CFA) still represents a dominant and flexible statistical framework to work out this potential cultural bias in a simultaneous way. With this dissertation I wanted to make an attempt to introduce new viewpoints on measurement invariance handled under covariance-based SEM framework by means of a consumer behavior modeling application on functional food choices.
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Workaholism is defined as the combination of two underlying dimensions: working excessively and working compulsively. The present thesis aims at achieving the following purposes: 1) to test whether the interaction between environmental and personal antecedents may enhance workaholism; 2) to develop a questionnaire aimed to assess overwork climate in the workplace; 3) to contrast focal employees’ and coworkers’ perceptions of employees’ workaholism and engagement. Concerning the first purpose, the interaction between overwork climate and person characteristics (achievement motivation, perfectionism, conscientiousness, self-efficacy) was explored on a sample of 333 Dutch employees. The results of moderated regression analyses showed that the interaction between overwork climate and person characteristics is related to workaholism. The second purpose was pursued with two interrelated studies. In Study 1 the Overwork Climate Scale (OWCS) was developed and tested using a principal component analysis (N = 395) and a confirmatory factor analysis (N = 396). Two overwork climate dimensions were distinguished, overwork endorsement and lacking overwork rewards. In Study 2 the total sample (N = 791) was used to explore the association of overwork climate with two types of working hard: work engagement and workaholism. Lacking overwork rewards was negatively associated with engagement, whereas overwork endorsement showed a positive association with workaholism. Concerning the third purpose, using a sample of 73 dyads composed by focal employees and their coworkers, a multitrait-multimethod matrix and a correlated trait-correlated method model, i.e. the CT-C(M–1) model, were examined. Our results showed a considerable agreement between raters on focal employees' engagement and workaholism. In contrast, we observed a significant difference concerning the cognitive dimension of workaholism, working compulsively. Moreover, we provided further evidence for the discriminant validity between engagement and workaholism. Overall, workaholism appears as a negative work-related state that could be better explained by assuming a multi-causal and multi-rater approach.
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Untersucht werden Prozess-Ergebnis-Zusammenhänge einer kognitiv-verhaltenstherapeutischen Gruppentherapie für Diabetes und Depression im Rahmen der DAD-Studie. rnAufgrund des Mangels an geeigneten Erhebungsinstrumenten der validen, ökonomischen und komplementären Sitzungsbewertung von Gruppenpatienten und -therapeuten wurden angelehnt an einen Patienten- (GTS-P) zwei Therapeutenstundenbögen entwickelt: der GTS-T zur Bewertung der Gesamtgruppe und der GTS-TP zur Bewertung einzelner Patienten. Die GTS-Bögen zeigen bei der Überprüfung der Testgüte insgesamt gute Itemparameter und Reliabilitäten. Das in den exploratorischen Faktorenanaylsen des GTS-P identifizierte zweifaktorielle Modell (1. wahrgenommene Zuversicht hinsichtlich der Gruppentherapie, 2. wahrgenommene persönliche Beteiligung) kann in den konfirmatorischen Faktorenanalysen bestätigt werden. Dazu wurden GTS-P-Daten aus einer Untersuchung mit Patienten mit somatoformen Störungen (Schulte, 2001) einbezogen. Den Ergebnissen der Item- und Faktorenanalysen folgend, wurden zwei Items des GTS-P und zwei weitere Items des GTS-T aus den Instrumenten ausgeschlossen. Für den GTS-T zeigt sich eine einfaktorielle, für den GTS-TP eine zum GTS-P parallele zweifaktorielle Struktur. rnIn den Mehrebenenanalysen zur Vorhersage des Therapieergebnisses (Post-Depressionssymptomatik) zeigt sich die Skala Zuversicht des GTS-P zu Therapiebeginn (1.-4. Sitzung) kontrolliert an der Skala Beteiligung und der Prä-Symptomatik, als valider Prädiktor. Das Item 5 „Anregungen“ (Skala Zuversicht) und Item 2 „Aktive Mitwirkung“ (Skala Beteiligung) sind am stärksten an diesem Effekt beteiligt, da diese Itemkombination das Therapieergebnis ebenfalls valide vorhersagen kann. Die Prognose ist schon durch die Werte der ersten Gruppentherapiesitzungen in der Remoralisierungsphase (Howard et al., 1993) möglich und verbessert sich nicht bei Berücksichtigung aller 10 Gruppensitzungen. Die Therapeutenbögen zeigen keine prädiktive Validität. Bedeutsame Zusammenhänge der Patienten- und Therapeutenbewertungen finden sich lediglich für den GTS-P und GTS-TP. Weitere Prädiktoren, wie der Diabetestyp, Diabeteskomplikationen und die Adhärenz, konnten nicht zur Verbesserung der Vorhersage beitragen. Für sekundär überprüfte Kriterien gelang die Prognose lediglich für ein weiteres Maß der Depressionssymptomatik und für eine Gesamtbewertung der Gruppentherapie durch die Patienten zu Therapieende. Bei der deskriptiven Betrachtung der Prozessqualität der DAD-Gruppentherapien zeigen sich positive, über den Verlauf der Gruppe zunehmende und nach Therapiephasen differenzierbare Bewertungsverläufe. rnDie Ergebnisse der Studie sprechen für die Relevanz von unspezifischen Wirkfaktoren für das Therapieergebnis von kognitiv-behavioralen Gruppentherapien. Die von den Gruppenpatienten wahrgenommene Zuversicht und Beteiligung als Zeichen der Ansprechbarkeit auf die Therapie sollte mit Hilfe von Stundenbögen, wie den GTS-Bögen, von Gruppentherapeuten zur Prozessoptimierung und Prävention von Therapieabbrüchen und Misserfolgen beachtet werden. rn
Resumo:
In dieser Masterarbeit wird die Frage untersucht, ob sich in den mittel- und osteuropäischen EU-Mitgliedsländern der Erweiterungsrunde von 2004 (Estland, Litauen, Polen, Slowakei, Slowenien, Ungarn, Tschechien) in der Befürwortung verschiedener normativer Demokratiemodelle Unterschiede zwischen der jüngsten und den älteren Generationen finden lassen. Diese demokratischen Wertorientierungen spielen für die Persistenz der noch jungen Demokratien eine entscheidende Rolle. Eine Inkongruenz des mehrheitlich favorisierten Demokratiemodells einerseits und der institutionellen Struktur andererseits kann zu Spannungen und Instabilität des politischen Systems führen. Theoretisch werden zwei Demokratiekonzeptionen unterschieden: Das Modell der liberalen Demokratie und das Modell der sozialistischen Demokratie. Dem Sozialisationsansatz folgend, sollte die jüngste Generation ein liberales Demokratiemodell eher und ein sozialistisches Demokratiemodell weniger befürworten als die älteren Generationen. In der empirischen Analyse auf Basis der Daten der sechsten Welle des European Social Survey von 2012 wird zunächst durch konfirmatorische Faktorenanalysen die konzeptuelle Trennung beider Modelle bestätigt. In der Regressionsanalyse wird der Fokus durch die Untersuchung verschiedener Kohorten gelegt, zusätzlich wird für situative Faktoren und mögliche Alterseffekte kontrolliert. Die Ergebnisse der Modellschätzungen zeichnen ein heterogenes Bild. In keinem der untersuchten Länder zeigt sich eine signifikant höhere Zustimmung zum liberalen Demokratiemodell durch die jüngste Generation, wie es der theoretischen Erwartung entsprechen würde. Stattdessen finden sich entweder keine signifikanten Unterschiede zwischen den Generationen oder sogar signifikant niedrigere Zustimmungswerte durch die jüngste Generation. Bei der Befürwortung eines sozialistischen Demokratiemodells entsprechen die Ergebnisse teilweise der theoretischen Erwartung: In einigen Ländern finden sich signifikant niedrigere Zustimmungswerte in der jüngsten Generation.
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The Working Alliance Inventory-Short Revised (WAI-SR) is a recently refined measure of the therapeutic alliance that assesses three key aspects of the therapeutic alliance: (a) agreement on the tasks of therapy, (b) agreement on the goals of therapy and (c) development of an affective bond. The WAI-SR demonstrated good psychometric properties in an initial validation in psychotherapy outpatients in the USA. The generalizability of these findings is limited because in some countries a substantial portion of individual psychotherapy is delivered in inpatient settings. This study investigated and compared the psychometric properties of the WAI-SR in German outpatients (N = 88) and inpatients (N = 243). In both samples reliability (alpha > 0.80) and convergent validity with the Helping Alliance Questionnaire were good (r > 0.64). Confirmatory factor analysis showed acceptable to good model fit for the proposed Bond-Task-Goal model in both samples. Multi-group analysis demonstrated that the same constructs were measured across settings. Alliance ratings of outpatients and inpatients differed regarding the overlap of alliance components and the magnitude of the alliance ratings: The differentiation of the alliance components was poorer in inpatients and they reported lower alliances. Unique aspects of the alliance in inpatient treatment are discussed and a need for further research on the alliance in inpatient settings is pointed out. Overall, the WAI-SR can be recommended for alliance assessment in both settings.
Resumo:
Background Depressive and anxiety symptoms often co-occur resulting in a debate about common and distinct features of depression and anxiety. Methods An exploratory factor analysis (EFA) and a bifactor modelling approach were used to separate a general distress continuum from more specific sub-domains of depression and anxiety in an adolescent community sample (n = 1159, age 14). The Mood and Feelings Questionnaire and the Revised Children's Manifest Anxiety Scale were used. Results A three-factor confirmatory factor analysis is reported which identified a) mood and social-cognitive symptoms of depression, b) worrying symptoms, and c) somatic and information-processing symptoms as distinct yet closely related constructs. Subsequent bifactor modelling supported a general distress factor which accounted for the communality of the depression and anxiety items. Specific factors for hopelessness-suicidal thoughts and restlessness-fatigue indicated distinct psychopathological constructs which account for unique information over and above the general distress factor. The general distress factor and the hopelessness-suicidal factor were more severe in females but the restlessness-fatigue factor worse in males. Measurement precision of the general distress factor was higher and spanned a wider range of the population than any of the three first-order factors. Conclusions The general distress factor provides the most reliable target for epidemiological analysis but specific factors may help to refine valid phenotype dimensions for aetiological research and assist in prognostic modelling of future psychiatric episodes.
Testing the structural and cross-cultural validity of the KIDSCREEN-27 quality of life questionnaire
Resumo:
OBJECTIVES: The aim of this study is to assess the structural and cross-cultural validity of the KIDSCREEN-27 questionnaire. METHODS: The 27-item version of the KIDSCREEN instrument was derived from a longer 52-item version and was administered to young people aged 8-18 years in 13 European countries in a cross-sectional survey. Structural and cross-cultural validity were tested using multitrait multi-item analysis, exploratory and confirmatory factor analysis, and Rasch analyses. Zumbo's logistic regression method was applied to assess differential item functioning (DIF) across countries. Reliability was assessed using Cronbach's alpha. RESULTS: Responses were obtained from n = 22,827 respondents (response rate 68.9%). For the combined sample from all countries, exploratory factor analysis with procrustean rotations revealed a five-factor structure which explained 56.9% of the variance. Confirmatory factor analysis indicated an acceptable model fit (RMSEA = 0.068, CFI = 0.960). The unidimensionality of all dimensions was confirmed (INFIT: 0.81-1.15). Differential item functioning (DIF) results across the 13 countries showed that 5 items presented uniform DIF whereas 10 displayed non-uniform DIF. Reliability was acceptable (Cronbach's alpha = 0.78-0.84 for individual dimensions). CONCLUSIONS: There was substantial evidence for the cross-cultural equivalence of the KIDSCREEN-27 across the countries studied and the factor structure was highly replicable in individual countries. Further research is needed to correct scores based on DIF results. The KIDSCREEN-27 is a new short and promising tool for use in clinical and epidemiological studies.
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This paper presents the German version of the Short Understanding of Substance Abuse Scale (SUSS) [Humphreys et al.: Psychol Addict Behav 1996;10:38-44], the Verstandnis von Storungen durch Substanzkonsum (VSS), and evaluates its psychometric properties. The VSS assesses clinicians' beliefs about the nature and treatment of substance use disorders, particularly their endorsement of psychosocial and disease orientation. The VSS was administered to 160 treatment staff members at 12 substance use disorder treatment programs in the German-speaking part of Switzerland. Because the confirmatory factor analysis of the VSS did not completely replicate the factorial structure of the SUSS, an exploratory factor analysis was undertaken. This analysis identified two factors: the Psychosocial model factor and a slightly different Disease model factor. The VSS Disease and Psychosocial subscales showed convergent and discriminant validity, as well as sufficient reliability.
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Impulsivity is a multifaceted construct that defines a range of maladaptive behavioral styles. The present research aimed to identify different dimensions of impulsive behavior in adolescents from a battery of laboratory behavioral assessments. In one analysis, correlations were examined between two self report and seven laboratory behavioral measures of impulsivity. The correlation between the two self report measures was high compared to correlations between the self report and laboratory behavioral measures. In a second analysis, a principal components analysis was performed with just the laboratory behavioral measures. Three behavioral dimensions were identified -- "impulsive decision-making", "impulsive inattention", and "impulsive disinhibition". These dimensions were further evaluated using the same sample with a confirmatory factor analysis, which did support the hypothesis that these are significant and independent dimensions of impulsivity. This research indicates there are at least three separate subtypes of impulsive behavior when using laboratory behavioral assessments with adolescent participants.
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Health literacy (HL) is context-specific. In public health and health promotion, HL in the private realm refers to individuals' knowledge and skills to prevent disease and to promote health in everyday life. However, there is a scarcity of measurement tools explicitly geared to private realm contexts. Our aim was to develop and test a short survey tool that captures different dimensions of HL in the context of family and friends. We used cross-sectional data from the Swiss Federal Surveys of Adolescents from 2010 to 2011, comprising 7983 males and 366 females between 18 and 25 years. HL was assessed through a set of eight items (self-reports). We used principal component analysis to explore the underlying factor structure among these items in the male sample and confirmatory factor analysis to verify the factor structure in the female sample. The results showed that the tested item set represented dimensions of functional, interactive and critical HL. Two sub-dimensions, understanding versus finding health-relevant information, denoted functional HL. Interactive and critical HL were each represented with two items. A sum score based on all eight items (Cronbach's α: 0.64) showed expected positive associations with own and parental education among males and females (p < 0.05). The short item set appears to be a feasible measurement tool to assess HL in the private realm. Its broader application in survey studies may help to improve our understanding of how this form of HL is distributed in the general population.
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Our study evaluates the dimensionality and equivalence of social trust across cultural contexts, using new data from Switzerland and the World Values Survey 2005–2008. Whereas some scholars assert that trust should be regarded as a coherent concept, others claim that trust is better conceived of as a multidimensional concept. In contrast to the conventional dichotomy of the forms of social trust, we identify three distinct forms of trust, namely, particularized, generalized, and identity-based trust. Moreover, we dispute the view that respondents understand the wording of survey questions regarding social trust differently between different cultural contexts, which would imply that comparative research on trust is a pointless endeavor. Applying multiple-group confirmatory factor analysis to the various constructs of social trust, we conclude that one may study relationships among the three forms of trust and other theoretical constructs as well as compare latent means across cultural contexts. Our analyses therefore provide an optimistic outlook for future comparative analyses that investigate forms of social trust across cultural contexts.
Resumo:
Background: The design of Virtual Patients (VPs) is essential. So far there are no validated evaluation instruments for VP design published. Summary of work: We examined three sources of validity evidence of an instrument to be filled out by students aimed at measuring the quality of VPs with a special emphasis on fostering clinical reasoning: (1) Content was examined based on theory of clinical reasoning and an international VP expert team. (2) Response process was explored in think aloud pilot studies with students and content analysis of free text questions accompanying each item of the instrument. (3) Internal structure was assessed by confirmatory factor analysis (CFA) using 2547 student evaluations and reliability was examined utilizing generalizability analysis. Summary of results: Content analysis was supported by theory underlying Gruppen and Frohna’s clinical reasoning model on which the instrument is based and an international VP expert team. The pilot study and analysis of free text comments supported the validity of the instrument. The CFA indicated that a three factor model comprising 6 items showed a good fit with the data. Alpha coefficients per factor were 0,74 - 0,82. The findings of the generalizability studies indicated that 40-200 student responses are needed in order to obtain reliable data on one VP. Conclusions: The described instrument has the potential to provide faculty with reliable and valid information about VP design. Take-home messages: We present a short instrument which can be of help in evaluating the design of VPs.
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The factorial validity of the SF-36 was evaluated using confirmatory factor analysis (CFA) methods, structural equation modeling (SEM), and multigroup structural equation modeling (MSEM). First, the measurement and structural model of the hypothesized SF-36 was explicated. Second, the model was tested for the validity of a second-order factorial structure, upon evidence of model misfit, determined the best-fitting model, and tested the validity of the best-fitting model on a second random sample from the same population. Third, the best-fitting model was tested for invariance of the factorial structure across race, age, and educational subgroups using MSEM.^ The findings support the second-order factorial structure of the SF-36 as proposed by Ware and Sherbourne (1992). However, the results suggest that: (a) Mental Health and Physical Health covary; (b) general mental health cross-loads onto Physical Health; (c) general health perception loads onto Mental Health instead of Physical Health; (d) many of the error terms are correlated; and (e) the physical function scale is not reliable across these two samples. This hierarchical factor pattern was replicated across both samples of health care workers, suggesting that the post hoc model fitting was not data specific. Subgroup analysis suggests that the physical function scale is not reliable across the "age" or "education" subgroups and that the general mental health scale path from Mental Health is not reliable across the "white/nonwhite" or "education" subgroups.^ The importance of this study is in the use of SEM and MSEM in evaluating sample data from the use of the SF-36. These methods are uniquely suited to the analysis of latent variable structures and are widely used in other fields. The use of latent variable models for self reported outcome measures has become widespread, and should now be applied to medical outcomes research. Invariance testing is superior to mean scores or summary scores when evaluating differences between groups. From a practical, as well as, psychometric perspective, it seems imperative that construct validity research related to the SF-36 establish whether this same hierarchical structure and invariance holds for other populations.^ This project is presented as three articles to be submitted for publication. ^
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Childhood obesity is one of the greatest public health challenges in Western countries. Abnormal eating behavior is thought to be a developmental trajectory to obesity. The Eating Pattern Inventory for Children (EPI-C) has not been used for children as young as eight years, and possible associations with body weight have not yet been established. Five hundred and twenty-one children of the Ulm Birth Cohort Study (UBCS; age eight) filled out the EPI-C and BMI was assessed. Adequacy of the scales was tested with confirmatory factor analysis and a MANOVA and cluster analysis established associations between eating patterns and BMI. The factor structure of the EPI-C was confirmed (GFI = .968) and abnormal eating behavior was associated with overweight (χ2(8) = 79.29, p<.001). The EPI-C is a valid assessment tool in this young age group. Overweight children consciously restrain their eating.
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Das State-Trait-Angstinventar (STAI) ist eines der am häufigsten eingesetzten Erhebungsinstrumente im Bereich der Angstdiagnostik. Die STAI-Skala zur Erfassung von Zustandsangst umfasst 20 Items. Unter bestimmten Erhebungsbedingungen erweist es sich als relativ schwierig, eine große Menge an Items zu bearbeiten oder aber es steht nicht ausreichend Testzeit zur Verfügung. Daher war es das Ziel der vorliegenden Studie, eine Kurzform der State-Version des STAI zu entwickeln. An einer Stichprobe von N = 65 Studierenden wurde aufgrund inhaltlicher und statistischer Kriterien eine Kurzform der State-Version des STAI, das STAI-SKD, mit fünf Items generiert. Eine konfirmatorische Faktorenanalyse an einer zweiten Stichprobe von N = 191 Studierenden zeigte, dass das STAI-SKD die Angstkomponenten Emotionality und Worry abbildet. Die Beziehungen des STAI-SKD zu positivem und negativem Affekt sowie dessen Veränderungssensitivität fielen in einer dritten Stichprobe (N = 80 Studierende) erwartungsgemäß aus. Die neue Kurzform der State-Version des STAI erlaubt eine ökonomische Erfassung der Zustandsangst.