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51.
Mediation analysis uses measures of hypothesized mediating variables to test theory for how a treatment achieves effects on outcomes and to improve subsequent treatments by identifying the most efficient treatment components. Most current mediation analysis methods rely on untested distributional and functional form assumptions for valid conclusions, especially regarding the relation between the mediator and outcome variables. Propensity score methods offer an alternative whereby the propensity score is used to compare individuals in the treatment and control groups who would have had the same value of the mediator had they been assigned to the same treatment condition. This article describes the use of propensity score weighting for mediation with a focus on explicating the underlying assumptions. Propensity scores have the potential to offer an alternative estimation procedure for mediation analysis with alternative assumptions from those of standard mediation analysis. The methods are illustrated investigating the mediational effects of an intervention to improve sense of mastery to reduce depression using data from the Job Search Intervention Study (JOBS II). We find significant treatment effects for those individuals who would have improved sense of mastery when in the treatment condition but no effects for those who would not have improved sense of mastery under treatment. 相似文献
52.
In this paper we study some questions concerning ?ukasiewicz implication algebras. In particular, we show that every subquasivariety of ?ukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite ?ukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains. 相似文献
53.
54.
Although homework completion is said to be rather important to achievement, nowadays there is a growing concern of educators about the increasing number of students who do not engage properly on doing the homework tasks and the subsequent impact on school failure rates. Focusing on English as a Foreign Language (EFL) and using a sample of 591 Portuguese fifth and sixth graders, the present study analyses the role played by a number of homework variables on students' achievement (proximal and distal), and their mediating role on the use of self-regulated learning strategies and perceived self-efficacy in the domain. Data confirm the indirect effect of homework on school achievement, by means of the referred cognitive and motivational variables (use of self-regulated learning strategies and self-efficacy). These findings are further discussed in order to highlight the significant role homework completion can play on fighting school failure. 相似文献
55.
The purpose of this work was to determine the epidemiological evolution of the Oppositional Defiant Disorder (ODD) in adolescents, using a sample of Secondary School students of the region of Campo de Gibraltar (Cadiz). The students' age ranged from 12 to 16 years old. Two evaluations were completed, the first one during the school year 2001-2002 and the second one in the school year 2006-2007. The sample comprised 2310 students in the first study and 2351 students in the second one. We used a comparative-selective approach. The results of the comparison revealed a prevalence ranging from 3.77% to 3.83% of students with this disorder, maintaining the main symptoms and with some changes in its distribution as a function of the school grade. Indeed, the data showed more cases in the final courses (1st study) in contrast with a higher concentration of cases in the initial courses (2nd study). With regard to the frequency of ODD by sex, we found that whereas in the earlier study (2001-2002), the relationship between boys and girls was 3.5:1, in the school year 2006/2007, the number of boys with ODD quadrupled the number of girls. 相似文献
56.
Calderón-Garcidueñas L Engle R Mora-Tiscareño A Styner M Gómez-Garza G Zhu H Jewells V Torres-Jardón R Romero L Monroy-Acosta ME Bryant C González-González LO Medina-Cortina H D'Angiulli A 《Brain and cognition》2011,77(3):345-355
Exposure to severe air pollution produces neuroinflammation and structural brain alterations in children. We tested whether patterns of brain growth, cognitive deficits and white matter hyperintensities (WMH) are associated with exposures to severe air pollution. Baseline and 1 year follow-up measurements of global and regional brain MRI volumes, cognitive abilities (Wechsler Intelligence Scale for Children-Revised, WISC-R), and serum inflammatory mediators were collected in 20 Mexico City (MC) children (10 with white matter hyperintensities, WMH+, and 10 without, WMH−) and 10 matched controls (CTL) from a low polluted city. There were significant differences in white matter volumes between CTL and MC children - both WMH+ and WMH− - in right parietal and bilateral temporal areas. Both WMH− and WMH+ MC children showed progressive deficits, compared to CTL children, on the WISC-R Vocabulary and Digit Span subtests. The cognitive deficits in highly exposed children match the localization of the volumetric differences detected over the 1 year follow-up, since the deficits observed are consistent with impairment of parietal and temporal lobe functions. Regardless of the presence of prefrontal WMH, Mexico City children performed more poorly across a variety of cognitive tests, compared to CTL children, thus WMH+ is likely only partially identifying underlying white matter pathology. Together these findings reveal that exposure to air pollution may perturb the trajectory of cerebral development and result in cognitive deficits during childhood. 相似文献
57.
Douglas N. Morris Jo Stecher Kayla M. Briggs-Peppler Chelsea M. Chittenden Joseph Rubira Lindsay K. Wismer 《Journal of religion and health》2014,53(1):27-36
This mixed-method study examined the responses of 97 occupational therapists on the subject of spirituality in occupational therapy practice. The inclusion of spirituality into the Occupational Therapy Practice Framework (2008) implies that clinicians address spirituality as a component of client-centered practice. This research revealed a gap between education, theory, and practice as evidenced in the quantitative and qualitative data. Although occupational therapy is intended to be holistic, therapists require a more complete understanding of what spirituality is and what the role of the occupational therapist is when addressing spirituality in evaluation or treatment. The discussion of this research provides information for future occupational therapy educators and educational programs as they seek to incorporate the construct of spirituality into curricula. 相似文献
58.
Luciana Burgugi Banin Nadielle Brandani Suzart Fernando Augusto Garcia Guimarães Alessandra L. G. Lucchetti Marcos Antonio Santos de Jesus Giancarlo Lucchetti 《Journal of religion and health》2014,53(3):917-928
The present study aims to understand the relation between religious beliefs, physicians’ behavior and patients’ opinions regarding “Spirituality, religiosity and health (S/R)” issues, and what makes a patient more prone to accept a physician to address his/her spiritual issues. A cross-sectional study was carried out in outpatients from a tertiary hospital, and a path analysis was used to examine the direct and indirect relationships between the variables. For the final analysis, 300 outpatients were evaluated. Most patients would like their doctors to address S/R issues but did not feel comfortable to ask them. In contrast, they reported most doctors have never addressed S/R issues, and they believe doctors are not prepared to address these issues. The path analysis revealed that patients’ previous experiences with their doctors may be as important as their religious/spiritual beliefs in proneness to accept a physician to address his/her spiritual issues. 相似文献
59.
Saveria Colonna Michel Charolles Laure Sarda Joël Pynte 《Journal of psycholinguistic research》2014,43(6):771-790
A challenge for psycholinguistics is to describe how linguistic cues influence the construction of the mental representation resulting from the comprehension of a text. In this paper, we will focus on one of these linguistic devices: the sentence-initial positioning of spatial adverbials such as In the park.... Three self-paced reading experiments were conducted to test the ‘Discourse Framing Hypothesis’ according to which preposed adverbials can be seen as frame builders announcing that incoming contents satisfy the same informational criterion specified by the adverbial. Our results indicate that spatial adverbials do not play the same role when they are in sentence-initial and in sentence-final position. These results are discussed in the framework of Zwaan’s Event Indexing Model. 相似文献
60.
Significant changes in endogenous plasma hormone levels are required to sustain pregnancy which provides a unique opportunity to study their effect on cognitive function. 相似文献