156 research outputs found

    Method effects associated with negatively and positively worded items on the 12-item General Health Questionnaire (GHQ-12) : results from a cross-sectional survey with a representative sample of Catalonian workers

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    This study focused on the examination of the latent structure underlying the responses to the GHQ-12, considering the role of method effects associated with both, PW and NW items, and using two alternative parameterisations of the CFA measurement models. What should first be noted is that the studies that have included method effects in the measurement model of the GHQ-12 have been more the exception than the rule in previous research into the factor structure of this questionnaire. According to the results of the present study, we conclude that the GHQ-12 factor structure is best characterised by introducing latent method factors that capture both the method effects associated with NW and PW items (model 7). These results support the conclusion from previous research that the good fit obtained by multidimensional models (mainly the two-factor model and the three-factor Graetz's model) could simply be explained by the artificial grouping of PW and NW items. However, the interpretation of the latent (method) factors as purely integrating method bias due to wording is not straightforward. It is obvious that NW and PW items share the wording. It is also clear that this three bifactor model (one trait and two method factors) fitted the data best. And finally, there is a lot of empirical evidence on these wording effects. However, it is also relevant to discuss the large loadings of many items on the method factors, being these loadings sometimes larger than their loadings in the trait factor. The general factor explains a 52% of the shared variance, but there are some items that deserve careful attention. For example, items 3 ('playing useful part in things') and 4 ('capable of making decisions') had very low loadings on the trait factor. If we understand PW method factor as the only method bias, then it follows that these two items are purely method effects, but surely they must share some trait variance. In the same vein, items 10 ('losing confidence in yourself') and 11 ('thinking of yourself as a worthless person') load very high in the NW method factor and, as a reviewer pointed out, a likely (post-hoc) explanation is that wording bias are still confounded with a confidence/self-image factor. Therefore, the interpretation of these effects as purely method and, accordingly, the interpretation of an overall score for the scale difficult may be compromised. The second aim of this study was to examine the relationship between the method factors associated with both NW and PW items and three demographic variables, namely sex, age and educational level of the respondents. Regarding the sex, we found a statistically significant, but weak, relationship between PW and sex, so that men were more likely than women to endorse PW items. These results are in line with previous works that, in the context of RSES, have found sex differences in wording effects. 56 57 As for the explanatory role of age on method effects, we found that the relationship between age and the NW effect was not statistically significant, which supports previous research using other questionnaires (eg, self-esteem scales, 50 Hospital Anxiety & Depression Scale 64). Moreover, our results give support to previous studies which had stated that, in older adults, the strongest method effects would be associated with PW items, rather than NW items. 55 58 As to the educational level, we found that there was not a significant correlation of this variable on the two method factors. This result supports and extends the evidence obtained in Tomás et al 50 who found that the educational level of the respondents had no effect on the negative method factor using self-esteem questionnaires. This results contradicts previous research on the relationship of the NW factor and the educational level/verbal ability with different questionnaires and samples. 41 64-69 Overall, the significant effects of sex and age on trait and method factors point out that women have a worse well-being, but this effect is partly modified by a method effect on the PW items, whereas the results for age suggest that older respondents have worse well-being and this effect is magnified by a method effect on the PW factor. The results on the individual differences related to the demographic variables considered in this study cannot only help to understand the presence of wording method effects but also to identify respondents who are prone to answering PW and NW items differently. In this sense, the relationship that appears as more evident is for the age and sex variables. Another practical consequence of our study concerns the relationship between the intended measure of the GHQ-12 (ie, the GPH factor) and other constructs of interest. Several studies have shown that method effects can inflate, deflate or have no effect at all on estimates of the relationship between two constructs (see Podsakoff et al 70 for a further review of the effects that method biases have on individual measures and on the covariation between different constructs). Thus, it is desirable that both the constructs of interest as well as the effects of method factors, like PW and NW, are considered in SEM models as a means of controlling these systematic sources of bias, and thus avoiding the drawing of inaccurate conclusions about the relationship between the substantive factors. Previous research on the GHQ-12 31 36 has outlined the asymmetry in the participants' responses as a function of the wording of the items, as well as the different responses scales for the PW and NW items. This asymmetry in the participants' responses as a function of the wording of the items is consistent with results from previous research into wording effects for contrastive survey questions. 71 The extent to which the presence of method effects is linked to the asymmetric pattern of responses and/or to the different response scales for the PW and NW items in the GHQ-12 should be examined in future research. Comparing the current work with previous studies into the factorial structure of the GHQ-12, to our knowledge, this is the first study that tests a comprehensive set of models including method effects associated with both PW and NW items and also explores some demographic correlates of these method effects. Another strength of this work was the fact that it used a large representative sample of workers, but the results might not be generalised to other specific populations, for example, adolescents and elderly retired people. Twitter @jmlosilla, @VivesJ_Research Contributors All authors meet the criteria recommended by the International Committee of Medical Journal Editors (ICMJE). All authors made substantial contributions to conception and design, acquisition of data or analysis and interpretation of data. MFR and JGM: drafted the article. JV and JML: critically revised the draft for important intellectual content. JMT: worked in the statistical analysis and interpretation of data. All authors agreed on the final version. Funding This work was supported by the Grant PGC2018-100675-B-I00, Spanish Ministry of Science, Innovation and Universities (Spain). The funders had no role in the study design, data collection and analysis, decision to publish or preparation of the manuscript. Disclaimer All authors have agreed to authorship in the indicated order. All authors declare that this paper is an original unpublished work and it is not being submitted elsewhere. All authors do not have any financial interests that might be interpreted as influencing the research, and APA ethical standard were followed in the conduct of the study. Competing interests None declared. Patient consent for publication Not required. Ethics approval The research was not submitted to approval by an institutional review board since this is not a requirement at our universities for this type of study. Ethics approval was not sought for this study since this was a secondary analysis of anonymised data. Provenance and peer review Not commissioned; externally peer reviewed. Data availability statement Data are available upon reasonable request.Objective Recent studies into the factorial structure of the 12-item version of the General Health Questionnaire (GHQ-12) have shown that it was best represented by a single substantive factor when method effects associated with negatively worded (NW) items are considered. The purpose of the present study was to examine the presence of method effects, and their relationships with demographic covariates, associated with positively worded (PW) and/or NW items. Design A cross-sectional, observational study to compare a comprehensive set of confirmatory factor models, including method effects associated with PW and/or NW items with GHQ-12 responses. Setting Representative sample of all employees living in Catalonia (Spain). Participants 3050 participants (44.6% women) who responded the Second Catalonian Survey of Working Conditions. Results A confirmatory factor analysis showed that the best fitting model was a unidimensional model with two additional uncorrelated method factors associated with PW and NW items. Furthermore, structural equation modelling (SEM) revealed that method effects were differentially related to both the sex and age of the respondents. Conclusion Individual differences related to sex and age can help to identify respondents who are prone to answering PW and NW items differently. Consequently, it is desirable that both the constructs of interest as well as the effects of method factors are considered in SEM models as a means of avoiding the drawing of inaccurate conclusions about the relationships between the substantive factors

    Assessment of the mobility of metals in a mining-impacted coastal area (Spain, Western Mediterranean)

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    A study on metal mobilisation (Zn, Pb and As) from contaminated sediments in Portman Bay (SE Spain) was carried out. Thisarea has suffered a major impact from mining activity, as millions of tons of mine tailings have been dumped into the bay over a long period, gradually filling the bay. A three-step sequential extraction procedure, modified from the BCR (Community Bureau of Reference) method, as well as selective extractions (H2O, 0.1 N HNO3, citrate–dithionite and 1 M NH4OAc after H2O2 attack) were applied to selected samples in order to evaluate the potential mobility of fixed metals. Acid volatile sulfides (AVS) and simultaneously extracted metals (SEM) were also determined. X-ray diffraction (XRD) and scanning electron microscopy coupled to with an energy-dispersion spectrometry (SEM-EDS) were applied to the characterization of both raw samples and the residues remaining after each extraction, providing additional information about the sediment phases carrying the metals studied. Metals associated with sediments showed different behaviour depending on the mineralogical phase they were bound to. Zn was the most labile metal, while Pb and As showed a lower mobility. The fraction of metals associated with jarosites presented a high stability under different physicochemical conditions, while metals associated with mineralogical phases that are undergoing supergenic alteration processes presented a high mobility. The results obtained may be useful to assess both the short and the long-term environmental impact of such disposal activities as well as supporting decisions for a future remediation of the zone

    SEOM-GEMCAD-TTD clinical guidelines for localized rectal cancer (2021)

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    The management of localized rectal cancer requires a multidisciplinary approach to optimize outcomes, reduce morbidity and prevent under or overtreatments. While early stages may obtain benefit of local resections without any additional therapies, locally advanced rectal cancer becomes a challenge defining the better sequential strategy of surgery, radiotherapy and chemotherapy. The latest results of international phase III studies have positioned the total neoadjuvant therapy as a potential new standard of care in high risk rectal cancers, however, the best schedule is still not well defined

    CSF Chitinase 3–Like 2 Is Associated With Long-term Disability Progression in Patients With Progressive Multiple Sclerosis

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    Multiple Sclerosis; ChitinaseEsclerosis múltiple; QuitinasaEsclerosi múltiple; QuitinasaObjective This study aimed to identify long-term prognostic protein biomarkers associated with disease progression in patients with progressive multiple sclerosis (MS). Methods CSF samples were collected from a discovery cohort of 28 patients with progressive MS who participated in a clinical trial with interferon beta. Patients were classified into high and low disability progression phenotypes according to numeric progression rates (NPR) and step-based progression rates (SPR) after a mean follow-up time of 12 years. Protein abundance was measured by shotgun proteomics. Selected proteins from the discovery cohort were quantified by parallel reaction monitoring in CSF samples from an independent validation cohort of 41 patients with progressive MS classified also into high and low disability progression phenotypes after a mean follow-up time of 7 years. Results Of 2,548 CSF proteins identified in the discovery cohort, 10 were selected for validation based on their association with long-term disability progression: SPATS2-like protein, chitinase 3–like 2 (CHI3L2), plasma serine protease inhibitor, metallothionein-3, phospholipase D4, beta-hexosaminidase, neurexophilin-1, adipocyte enhancer-binding protein 1, cathepsin L1, and lipopolysaccharide-binding protein. Only CHI3L2 was validated, and patients with high disability progression exhibited significantly higher CSF protein levels compared with patients with low disability progression (p = 0.03 for NPR and p = 0.02 for SPR). CHI3L2 levels showed good performance to discriminate between high and low disability progression in patients with progressive MS (area under the curve 0.73; sensitivity 90% and specificity 63%). Conclusions Although further confirmatory studies are needed, we propose CSF CHI3L2 as a prognostic protein biomarker associated with long-term disability progression in patients with progressive MS.This work was funded by grants from the International Progressive MS Alliance (grant no. PA0020), Asociación Esclerosis Múltiple (EME)—Red Española de Esclerosi múltiple (REEM), REEM (RD16/0015/002 and RD16/0015/003) cofunded by the Instituto de Salud Carlos III and Fondo Europeo de Desarrollo Regional (FEDER, Otra manera de hacer Europa)

    Research at the learning and vision mobile robotics group 2004-2005

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    Spanish Congress on Informatics (CEDI), 2005, Granada (España)This article presents the current trends on wheeled mobile robotics being pursued at the Learning and Vision Mobile Robotics Group (IRI). It includes an overview of recent results produced in our group in a wide range of areas, including robot localization, color invariance, segmentation, tracking, audio processing and object learning and recognition.This work was supported by projects: 'Supervised learning of industrial scenes by means of an active vision equipped mobile robot.' (J-00063), 'Integration of robust perception, learning, and navigation systems in mobile robotics' (J-0929).Peer Reviewe

    HACEK infective endocarditis: epidemiology, clinical features outcome: A case-control study

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    OBJECTIVES: The study aimed to describe the epidemiology, microbiological and clinical features of a population sample of 17 patients with HACEK-IE and to compare them with matched control patients with IE caused by Viridans group Streptococci (VGS-IE). METHODS: Description of definite (14; 82.2%) and possible (3; 17.6%) HACEK-IE included in the 'Infective Endocarditis Hospital Clínic of Barcelona' (IE-HCB) database between 1979 and 2016. Furthermore, a retrospective case-control analysis was performed, matching each case to three VGS-IE controls registered in the same database during the same period of time. RESULTS: Seventeen out of 1,209 IE cases (1.3%, 95%CI 0.69-1.91) were due to HACEK group. The most frequent isolated HACEK species were Aggregatibacter spp (11; 64.7%). Intracardiac vegetations were present in 70.6% of cases. Left heart failure (LHF) was present in 29.4% of cases. Ten patients (58.8%) required in-hospital surgery and none died during hospitalization. In the case-control analysis, there was a trend toward larger vegetations in the HACEK-IE group (median (IRQ) size=11.5 (10.0-20.0) mm vs 9.0 (7.0-13.0) mm; p=0.068). Clinical manifestations, echocardiographic findings, LHF rate, systemic emboli and other complications were all comparable (p >0.05). In-hospital surgery and mortality were similar for both groups. One-year mortality was lower for HACEK-IE (1/17 vs. to 6/48, p=0.006). CONCLUSIONS: HACEK-IE represented 1.3% of all IE cases. Clinical features and outcome were comparable with the VGS-IE control group. Despite the trend to

    Perovskite Photovoltaic Modules: Life Cycle Assessment of Pre-industrial Production Process

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    Photovoltaic devices based on perovskite materials have a great potential to become an exceptional source of energy while preserving the environment. However, to enter the global market, they require further development to achieve the necessary performance requirements. The environmental performance of a pre-industrial process of production of a large-area carbon stack perovskite module is analyzed in this work through life cycle assessment (LCA). From the pre-industrial process an ideal process is simulated to establish a benchmark for pre-industrial and laboratory-scale processes. Perovskite is shown to be the most harmful layer of the carbon stack module because of the energy consumed in the preparation and annealing of the precursor solution, and not because of its Pb content. This work stresses the necessity of decreasing energy consumption during module preparation as the most effective way to reduce environmental impacts of perovskite solar cells

    Depopulation impacts on ecosystem services in Mediterranean rural areas

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    Despite the exponential increase in human population at global scale, some rural areas have experienced a progressive abandonment over the last decades. Under particular socioecological and policy contexts, changes in demography may promote land-use changes and, consequently, alter ecosystem services (ES) supply. However, most studies on this topic have targeted urban population increase, whereas depopulation has been rarely addressed. Here, we examined how shifts in demographic variables (human population, population density, and number of villages) affect provisioning (water supply, food and biomass production) and regulating (soil retention, water and nutrient regulation) ES in Mediterranean rural areas with contrasting environmental, so-cioeconomic and land-use contexts. When depopulation results in underuse of socio-ecological systems, we ex-pected a decrease of provisioning and an increase of regulating ES, whereas we expected the opposite pattern when it results in land-use intensification. To test this hypothesis, we compared demographic data and ES estimated with Soil and Water Assessment Tool (SWAT) linked to land-use changes between the 1950s and 2000s in three rural areas of Arag ́on (NE Spain). Generalized Additive Mixed Models and Linear Mixed-Effect Models were used to analyze demographic trends, ES changes and the relationship between them. We found severe depopulation (− 42% inhabitants) and associated land-use changes in the three areas, which was particularly evident in isolated mountainous zones (− 63% inhabitants). Depopulation trends significantly affected land use and, consequently, all of the ES evaluated. In mountainous depopulated areas, land abandonment and rewilding resulted in the increase in water regulation (>1000%) and soil retention (>400%). In contrast, agriculture was intensified in more fertile and easy-to-access lowland areas, boosting the food production service (>600%). Accordingly, the interactions among depopulation, crop production and regulating ES should be considered in the management schemes and policies targeting rural areas for a balanced and sustainable supply of ES in the long term

    Effectiveness of vancomycin plus cloxacillin compared with vancomycin, cloxacillin and daptomycin single therapies in the treatment of methicillin-resistant and methicillin-susceptible Staphylococcus aureus in a rabbit model of experimental endocarditis

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    Objectives: To investigate if the addition of cloxacillin to vancomycin enhances the activity of both monotherapies for treating MSSA and MRSA experimental endocarditis (EE) in rabbits. Methods: Vancomycin plus cloxacillin was compared with the respective monotherapies and daptomycin. In vitro time-kill studies were performed using standard (105 cfu) and high (108 cfu) inocula of five MRSA, one glycopeptide-intermediate (GISA) and five MSSA strains. One MSSA (MSSA-678) and one MRSA (MRSA-277) strain were selected to be used in the in vivo model. A human-like pharmacokinetics model was applied and the equivalents of cloxacillin 2 g/4 h IV and daptomycin 6 mg/kg/day IV were administered. To optimize vancomycin activity, dosage was adjusted to achieve an AUC/MIC ≥400. Results: Daptomycin sterilized significantly more vegetations than cloxacillin (13/13, 100% versus 9/15, 60%; P = 0.02) and showed a trend of better activity than vancomycin (10/14, 71%; P = 0.09) and vancomycin plus cloxacillin (10/14, 71%; P = 0.09) against MSSA-678. Addition of cloxacillin to vancomycin (13/15, 87%) was significantly more effective than vancomycin (8/16, 50%; P = 0.05) and showed similar activity to daptomycin (13/18, 72%; P = 0.6) against MRSA-277. In all treatment arms, the bacterial isolates recovered from vegetations were re-tested and showed the same daptomycin susceptibility as the original strains. Conclusions: Vancomycin plus cloxacillin proved synergistic and bactericidal activity against MRSA. Daptomycin was the most efficacious option against MSSA and similar to vancomycin plus cloxacillin against MRSA. In settings with high MRSA prevalence, vancomycin plus cloxacillin might be a good alternative for empirical therapy of S. aureus IE
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