The psychometric properties of the Kessler Psychological Distress Scale (K6) in a general population sample of adolescents

The 6-item Kessler Psychological Distress Scale (K6; Kessler et al., 2002) is a screener for psychological distress that has robust psychometric properties among adults. Given that a significant proportion of adolescents experience mental illness, there is a need for measures that accurately and reliably screen for mental disorders in this age group. This study examined the psychometric properties of the K6 in a large general population sample of adolescents (N = 4,434; mean age = 13.5 years; 44.6% male). Factor analyses were conducted to examine the dimensionality of the K6 in adolescents and to investigate sex-based measurement invariance. This study also evaluated the K6 as a predictor of scores on the Strengths and Difficulties Questionnaire (SDQ; Goodman, 1997). The K6 demonstrated high levels of internal consistency, with the 6 items loading primarily on 1 factor. Consistent with previous research, females reported higher mean levels of psychological distress when compared with males. The identification of sex-based measurement noninvariance in the item thresholds indicated that these mean differences most likely represented reporting bias in the K6 items rather than true differences in the underlying psychological distress construct. The K6 was a fair to good predictor of abnormal scores on the SDQ, but predictive utility was relatively low among males. Future research needs to focus on refining and augmenting the K6 scale to maximize its utility in adolescents. (PsycINFO Database Record (c) 2015 APA, all rights reserved)

Ratkaiseeko raha? : Tulospalkkiojärjestelmään ja työympäristöön liittyvien kokemusten yhteys esimiesten työtyytyväisyyteen ja työmotivaatioon

The aim of this study was to investigate the relationship between merit pay system and work environment and foremen´s work satisfaction and work motivation. There has been a lot of investigation on rewarding. Less research has been done on previous surveys among the merit pay systems and motivation investigations. According to former surveys, rewarding systems cannot be released from its context. Therefore this survey expanded to deal with work environment. It was also essential to investigate different dimensions of extrinsic and intrinsic motivation and equity of rewarding. Investigation or work motivation and work satisfaction was challenging because both of these concepts have been investigated under quite traditional frame of reference of work motivation theories. In some surveys, the concepts have not been even separated or they have been used even as synonyms. The data were collected with the 193 foremen working in the profit centers of the different chains of the company in the field of retail trade. The questions were: Are the experiences of merit pay system and work environment related to foremen´s work satisfaction and work motivation? Are the backround variables related to foremen´s work satisfaction and work motivation? The data collection was carried out by an electronic inquiry during May 2010. 137 replied from foremen working under merit pay system. The research material was analyzed with PASW-software. Various analyzing methods were used: factor analyses, regression analyses and group of different parametric and non-parametric analyses. In contrast to theoretical framework in the factor analyses work satisfaction and work motivation clustered into the same dimension. As a main result the atmosphere, possibilities to influence and the atmosphere of leading were strongly positively related to foremen´s work satisfaction and work motivation. According to regression analyses these factors were able to explain 55 % of the foremen´s work satisfaction and work motivation. The best explanatory variable was atmosphere. Instead, the backround variables (age, sex, working years, group of profession, education) were not associated with work satisfaction and work motivation.

Effects of different modes of hot cross-rolling in 7010 aluminum alloy: part II. mechanical properties anisotropy

The influence of microstructure and texture developed by different modes of hot cross-rolling on in-plane anisotropy (A (IP)) of yield strength, work hardening behavior, and anisotropy of Knoop hardness (KHN) yield locus has been investigated. The A (IP) and work hardening behavior are evaluated by tensile testing at 0 deg, 45 deg, and 90 deg to the rolling direction, while yield loci have been generated by directional KHN measurements. It has been observed that specimens especially in the peak-aged temper, in spite of having a strong, rotated Brass texture, show low A (IP). The results are discussed on the basis of Schmid factor analyses in conjunction with microstructural features, namely grain morphology and precipitation effects. For the specimen having a single-component texture, the yield strength variation as a function of orientation can be rationalized by the Schmid factor analysis of a perfectly textured material behaving as a quasi-single crystal. The work hardening behavior is significantly affected by the presence of solute in the matrix and the state of precipitation rather than texture, while yield loci derived from KHN measurements reiterate the low anisotropy of the materials. Theoretic yield loci calculated from the texture data using the visco-plastic self-consistent model and Hill's anisotropic equation are compared with that obtained experimentally.

Ontogenetic shifts in natural diet during benthic stages of American lobster (Homarus americanus), off the Magdalen Islands

The natural diet of 506 American lobsters (Homarus americanus) ranging from instar V (4 mm cephalothorax length, CL) to the adult stage (112 mm CL) was determined by stomach content analysis for a site in the Magdalen Islands, Gulf of St. Lawrence, eastern Canada. Cluster and factor analyses determined four size groupings of lobsters based on their diet: <7.5 mm, 7.5 to <22.5 mm, 22.5 to <62.5 mm, and ≥62.5 mm CL. The ontogenetic shift in diet with increasing size of lobsters was especially apparent for the three dominant food items: the contribution of bivalves and animal tissue (flesh) to volume of stomach contents decreased from the smallest lobsters (28% and 39%, respectively) to the largest lobsters (2% and 11%, respectively), whereas the reverse trend was seen for rock crab Cancer irroratus (7% in smallest lobsters to 53% in largest lobsters). Large lobsters also ate larger rock crabs than did small lobsters.

集热栅对太阳能烟囱发电系统效率的影响

采用计算流体动力学（CFD）方法对太阳能烟囱发电装置进行数值模拟，得到装置内部的温度场、速度场、压力场等分布情况。对集热棚的各种几何和物理参数进行研究和分析。结果表明，集热棚直径、太阳辐照强度、覆盖材料的透明度等诸多参数对系统效率有直接而重要的影响。

Development of a general internet attitude scale and internet self-efficacy scale

The measurement of users’ attitudes towards and confidence with using the Internet is an important yet poorly researched topic. Previous research has encountered issues that serve to obfuscate rather than clarify. Such issues include a lack of distinction between the terms ‘attitude’ and ‘self-efficacy’, the absence of a theoretical framework to measure each concept, and failure to follow well-established techniques for the measurement of both attitude and self-efficacy. Thus, the primary aim of this research was to develop two statistically reliable scales which independently measure attitudes towards the Internet and Internet self-efficacy. This research addressed the outlined issues by applying appropriate theoretical frameworks to each of the constructs under investigation. First, the well-known three component (affect, behaviour, cognition) model of attitudes was applied to previous Internet attitude statements. The scale was distributed to four large samples of participants. Exploratory factor analyses revealed four underlying factors in the scale: Internet Affect, Internet Exhilaration, Social Benefit of the Internet and Internet Detriment. The final scale contains 21 items, demonstrates excellent reliability and achieved excellent model fit in the confirmatory factor analysis. Second, Bandura’s (1997) model of self-efficacy was followed to develop a reliable measure of Internet self-efficacy. Data collected as part of this research suggests that there are ten main activities which individuals can carry out on the Internet. Preliminary analyses suggested that self-efficacy is confounded with previous experience; thus, individuals were invited to indicate how frequently they performed the listed Internet tasks in addition to rating their feelings of self-efficacy for each task. The scale was distributed to a sample of 841 participants. Results from the analyses suggest that the more frequently an individual performs an activity on the Internet, the higher their self-efficacy score for that activity. This suggests that frequency of use ought to be taken into account in individual’s self-efficacy scores to obtain a ‘true’ self-efficacy score for the individual. Thus, a formula was devised to incorporate participants’ previous experience of Internet tasks in their Internet self-efficacy scores. This formula was then used to obtain an overall Internet self-efficacy score for participants. Following the development of both scales, gender and age differences were explored in Internet attitudes and Internet self-efficacy scores. The analyses indicated that there were no gender differences between groups for Internet attitude or Internet self-efficacy scores. However, age group differences were identified for both attitudes and self-efficacy. Individuals aged 25-34 years achieved the highest scores on both the Internet attitude and Internet self-efficacy measures. Internet attitude and self-efficacy scores tended to decrease with age with older participants achieving lower scores on both measures than younger participants. It was also found that the more exposure individuals had to the Internet, the higher their Internet attitude and Internet self-efficacy scores. Examination of the relationship between attitude and self-efficacy found a significantly positive relationship between the two measures suggesting that the two constructs are related. Implication of such findings and directions for future research are outlined in detail in the Discussion section of this thesis.

Self-neglect: development and evaluation of a self-neglect (SN-37) measurement instrument

Aim: To develop and evaluate the psychometric properties of an instrument for the measurement of self-neglect (SN).Conceptual Framework: An elder self-neglect (ESN) conceptual framework guided the literature review and scale development. The framework has two key dimensions physical/psycho-social and environmental and seven sub dimensions which are representative of the factors that can contribute to intentional and unintentional SN. Methods: A descriptive cross-sectional design was adopted to achieve the research aim. The study was conducted in two phases. Phase 1 involved the development of the questionnaire content and structure. Phase 2 focused on establishing the psychometric properties of the instrument. Content validity was established by a panel of 8 experts and piloted with 9 health and social care professionals. The instrument was subsequently posted with a stamped addressed envelope to 566 health and social care professionals who met specific eligibility criteria across the four HSE areas. A total of 341 questionnaires were returned, a response rate of 60% and 305 (50%) completed responses were included in exploratory factor analysis (EFA). Item and factor analyses were performed to elicit the instruments underlying factor structure and establish preliminary construct validity. Findings: Item and factor analyses resulted in a logically coherent, 37 items, five factor solution, explaining 55.6% of the cumulative variance. The factors were labelled: ‘Environment’, ‘Social Networks’, ‘Emotional and Behavioural Liability’, ‘Health Avoidance’ and ‘Self-Determinism’. The factor loadings were >0.40 for all items on each of the five subscales. Preliminary construct validity was supported by findings. Conclusion: The main outcome of this research is a 37 item Self-Neglect (SN-37) measurement instrument that was developed by EFA and underpinned by an ESN conceptual framework. Preliminary psychometric evaluation of the instrument is promising. Future work should be directed at establishing the construct and criterion related validity of the instrument.

Differential predictability of four dimensions of affect intensity.

Individual differences in affect intensity are typically assessed with the Affect Intensity Measure (AIM). Previous factor analyses suggest that the AIM is comprised of four weakly correlated factors: Positive Affectivity, Negative Reactivity, Negative Intensity and Positive Intensity or Serenity. However, little data exist to show whether its four factors relate to other measures differently enough to preclude use of the total scale score. The present study replicated the four-factor solution and found that subscales derived from the four factors correlated differently with criterion variables that assess personality domains, affective dispositions, and cognitive patterns that are associated with emotional reactions. The results show that use of the total AIM score can obscure relationships between specific features of affect intensity and other variables and suggest that researchers should examine the individual AIM subscales.

Dimensionality, Reliability and Validity of the InterRAI Depression Rating Scale in a Canadian Palliative Care Population

A reliable and valid instrument is needed to screen for depression in palliative patients. The interRAI Depression Rating Scale (DRS) is based on seven items in the interRAI Palliative Care instrument. This study is the first to explore the dimensionality, reliability and validity of the DRS in a palliative population. Palliative home care patients (n = 5,175) residing in Ontario (Canada) were assessed with the interRAI Palliative Care instrument. Exploratory factor analysis and Mokken scale analysis were used to identify candidate conceptual models and evaluate scale homogeneity/performance. Confirmatory factor analysis compared models using standard goodness-of-fit indices. Convergent and divergent validity were investigated by examining polychoric correlations between the DRS and other items. The “known groups” test determined if the DRS meaningfully distinguished among client subgroups. The non-hierarchical two factor model showed acceptable fit with the data, and ordinal alpha coefficients of 0.83 and 0.82 were observed for the two DRS subscales. Omega hierarchical (ωh) was 0.78 for the bifactor model, with the general factor explaining three quarters of the common variance. Despite the multidimensionality evident in the factor analyses, bifactor modelling and the Mokken homogeneity coefficient (0.34) suggest that the DRS is a coherent scale that captures important information on sub-constructs of depression (e.g., somatic symptoms). Higher correlations were seen between the DRS and mood and psychosocial well-being items, and lower correlations with functional status and demographic variables. The DRS distinguished in the expected manner for known risk factors (e.g., social support, pain). The results suggest that the DRS is primarily unidimensional and reliable for use in screening for depression in palliative care patients.

Genome-wide gene pathway analysis of psychotic illness symptom dimensions based on a new schizophrenia-specific model of the OPCRIT

Empirically derived phenotypic measurements have the potential to enhance gene-finding efforts in schizophrenia. Previous research based on factor analyses of symptoms has typically included schizoaffective cases. Deriving factor loadings from analysis of only narrowly defined schizophrenia cases could yield more sensitive factor scores for gene pathway and gene ontology analyses. Using an Irish family sample, this study 1) factor analyzed clinician-rated Operational Criteria Checklist items in cases with schizophrenia only, 2) scored the full sample based on these factor loadings, and 3) implemented genome-wide association, gene-based, and gene-pathway analysis of these SCZ-based symptom factors (final N= 507). Three factors emerged from the analysis of the schizophrenia cases: a manic, a depressive, and a positive symptom factor. In gene-based analyses of these factors, multiple genes had q<. 0.01. Of particular interest are findings for PTPRG and WBP1L, both of which were previously implicated by the Psychiatric Genomics Consortium study of SCZ; results from this study suggest that variants in these genes might also act as modifiers of SCZ symptoms. Gene pathway analyses of the first factor indicated over-representation of glutamatergic transmission, GABA-A receptor, and cyclic GMP pathways. Results suggest that these pathways may have differential influence on affective symptom presentation in schizophrenia.

Herd-level bovine tuberculosis risk factors: assessing the role of low-level badger population disturbance

Bovine TB (bTB) is endemic in Irish cattle and has eluded eradication despite considerable expenditure, amid debate over the relative roles of badgers and cattle in disease transmission. Using a comprehensive dataset from Northern Ireland (>10,000 km²; 29,513 cattle herds), we investigated interactions between host populations in one of the first large-scale risk factor analyses for new herd breakdowns to combine data on both species. Cattle risk factors (movements, international imports, bTB history, neighbours with bTB) were more strongly associated with herd risk than area-level measures of badger social group density, habitat suitability or persecution (sett disturbance). Highest risks were in areas of high badger social group density and high rates of persecution, potentially representing both responsive persecution of badgers in high cattle risk areas and effects of persecution on cattle bTB risk through badger social group disruption. Average badger persecution was associated with reduced cattle bTB risk (compared with high persecution areas), so persecution may contribute towards sustaining bTB hotspots; findings with important implications for existing and planned disease control programmes.

Promoting self-regulated learning in technology enhanced learning environments : keeping a digital track of the learning process

Tese de doutoramento (co-tutela), Psicologia (Psicologia da Educação), Faculdade de Psicologia da Universidade de Lisboa, Faculdade de Psicologia e de Ciências da Educação da Universidade de Coimbra, Technial University of Darmstadt, 2014

Structural Validity of the Wechsler Intelligence Scale for Children (WISC-IV) in a French-speaking Swiss sample

The Wechsler Intelligence Scale for Children-fourth edition (i.e. WISC-IV) recognizes a four-factor scoring structure in addition to the Full Scale IQ (FSIQ) score: Verbal Comprehension (VCI), Perceptual Reasoning (PRI), Working Memory (WMI), and Processing Speed (PSI) indices. However, several authors suggested that models based on the Cattell-Horn-Carroll (CHC) theory with 5 or 6 factors provided a better fit to the data than does the current four-factor solution. By comparing the current four-factor structure to CHC-based models, this research aimed to investigate the factorial structure and the constructs underlying the WISC-IV subtest scores with French-speaking Swiss children (N = 249). To deal with this goal, confirmatory factor analyses (CFAs) were conducted. Results showed that a CHC-based model with five factors better fitted the French-Swiss data than did the current WISC-IV scoring structure. All together, these results support the hypothesis of the appropriateness of the CHC model with French-speaking children.

Development and validation of the Transition to Retirement Questionnaire

The aim of this study was to present the initial validation of a new questionnaire, the Transition to Retirement Questionnaire (TRQ) and to study its relationship with resistance to change and personality dimensions. Based on Schlossberg's typology of the retired, the TRQ is designed to assess five dimensions related to personal perceptions of transition to retirement, retirement, and personal plans and activities. The sample consisted of 1,054 professionally active or retired adults from the Swiss French-speaking Canton of Vaud. Exploratory principal components and confirmatory factor analyses highlighted a five-factor solution that fit coherently with Schlossberg's typology. Moreover, TRQ dimensions were related to resistance to change tendencies and personality dimensions. The TRQ seems to be an interesting tool for use in research but also for interventions with young retirees or people preparing for retirement.

Psychometrics of the Dyadic Coping Inventory in three language groups

This article introduces the Dyadic Coping Inventory (DCI; Bodenmann, 2008) and aims (1) to investigate the reliability and aspects of the validity of the Italian and French versions of the DCI, and (2) to replicate its factor structure and reliabilities using a new Swiss German sample. Based on 216 German-, 378 Italian-, and 198 French-speaking participants, the factor structure of the original German inventory was able to be replicated by using principal components analysis in all three groups after excluding two items in the Italian and French versions. The latter were shown to be as reliable as the German version with the exception of the low reliabilities of negative dyadic coping in the French group. Confirmatory factor analyses provided additional support for delegated dyadic coping and evaluation of dyadic coping. Intercorrelations among scales were similar across all three languages groups with a few exceptions. Previous findings could be replicated in all three groups, showing that aspects of dyadic coping were more strongly related to marital quality than to dyadic communication. The use of the dyadic coping scales in the actor-partner interdependence model, the common fate model, and the mutual influence model is discussed.