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Andrew J. Mashburn Jason T. Downer Susan E. Rivers Marc A. Brackett Andres Martinez 《Prevention science》2014,15(2):146-155
Social and emotional learning programs are designed to improve the quality of social interactions in schools and classrooms in order to positively affect students’ social, emotional, and academic development. The statistical power of group randomized trials to detect effects of social and emotional learning programs and other preventive interventions on setting-level outcomes is influenced by the reliability of the outcome measure. In this paper, we apply generalizability theory to an observational measure of the quality of classroom interactions that is an outcome in a study of the efficacy of a social and emotional learning program called The Recognizing, Understanding, Labeling, Expressing, and Regulating emotions Approach. We estimate multiple sources of error variance in the setting-level outcome and identify observation procedures to use in the efficacy study that most efficiently reduce these sources of error. We then discuss the implications of using different observation procedures on both the statistical power and the monetary costs of conducting the efficacy study. 相似文献
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Susan Woolhouse Emily Cooper Angela Pickard 《The International journal on drug policy》2013,24(6):550-557
BackgroundInjection drug use (IDU) increases the risk of contracting hepatitis C virus (HCV) yet very few people living with HCV access effective, and potentially curative, treatments. The East Toronto Hepatitis C Program (ETHCP) was developed in 2006 and provides health care, treatment and support to people living with HCV who have complex mental health, physical health and psychosocial needs. The program is anchored in a 16–18 week psychosocial support group located within one of the 3 participating community-based health clinics. The objective of this study was to explore the experiences of individuals engaged in the ETHCP psycho-educational group.MethodsThis phenomenological qualitative study consisted of semi-structured in-depth interviews with twenty randomly selected program participants.ResultsThe three dominant themes that emerged from the analysis were program structure, group cohesion and group as agent for change. The ETHCP “one-stop shopping” model provided a stable foundation allowing for the development of group cohesion. Group cohesion was marked by the formation of intense relationships creating a safe and non-judgmental environment where participants could self-reflect, make social connections and feel cared for and accepted. Three types of relationships characterized group cohesion: relationship to self, relationships with individual group members and relationship to group as a whole. Within the nurturing group environment, participants could challenge themselves and others, ultimately enabling change.ConclusionThe results of our qualitative study suggest that it is the formation of strong group cohesion that facilitated participants’ behavioural change, regardless of their level of substance use. The structure of the group provided stability and was characterized by consistent weekly meetings, knowledge exchange and the provision of multiple services in one location. The support from peers and staff allowed participants to develop personal goals. Participants began to see themselves in a new and changed way; expressing this change in a variety of positive behaviours. 相似文献
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Penny F. Whiting Anne W.S. Rutjes Marie E. Westwood Susan Mallett 《Journal of clinical epidemiology》2013,66(10):1093-1104
ObjectiveTo classify the sources of bias and variation and to provide an updated summary of the evidence of the effects of each source of bias and variation.Study Design and SettingWe conducted a systematic review of studies of any design with the main objective of addressing bias or variation in the results of diagnostic accuracy studies. We searched MEDLINE, EMBASE, BIOSIS, the Cochrane Methodology Register, and Database of Abstracts of Reviews of Effects (DARE) from 2001 to October 2011. Citation searches based on three key papers were conducted, and studies from our previous review (search to 2001) were eligible. One reviewer extracted data on the study design, objective, sources of bias and/or variation, and results. A second reviewer checked the extraction.ResultsWe summarized the number of studies providing evidence of an effect arising from each source of bias and variation on the estimates of sensitivity, specificity, and overall accuracy.ConclusionsWe found consistent evidence for the effects of case–control design, observer variability, availability of clinical information, reference standard, partial and differential verification bias, demographic features, and disease prevalence and severity. Effects were generally stronger for sensitivity than for specificity. Evidence for other sources of bias and variation was limited. 相似文献
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Gabriela Novak Theresa Fan Brian F. O’Dowd Susan R. George 《International journal of developmental neuroscience》2013
The goal of this study was to determine whether two stressors commonly used to model aspects of neuropsychiatric disease in rats have an additive effect on striatal dopamine type 2 receptor (D2R) expression, a key player in the etiology of neuropsychiatric disease. 相似文献