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991.
Devin Incerti Michael T. Bretscher Ray Lin Chris Harbron 《Pharmaceutical statistics》2023,22(1):162-180
While randomized controlled trials (RCTs) are the gold standard for estimating treatment effects in medical research, there is increasing use of and interest in using real-world data for drug development. One such use case is the construction of external control arms for evaluation of efficacy in single-arm trials, particularly in cases where randomization is either infeasible or unethical. However, it is well known that treated patients in non-randomized studies may not be comparable to control patients—on either measured or unmeasured variables—and that the underlying population differences between the two groups may result in biased treatment effect estimates as well as increased variability in estimation. To address these challenges for analyses of time-to-event outcomes, we developed a meta-analytic framework that uses historical reference studies to adjust a log hazard ratio estimate in a new external control study for its additional bias and variability. The set of historical studies is formed by constructing external control arms for historical RCTs, and a meta-analysis compares the trial controls to the external control arms. Importantly, a prospective external control study can be performed independently of the meta-analysis using standard causal inference techniques for observational data. We illustrate our approach with a simulation study and an empirical example based on reference studies for advanced non-small cell lung cancer. In our empirical analysis, external control patients had lower survival than trial controls (hazard ratio: 0.907), but our methodology is able to correct for this bias. An implementation of our approach is available in the R package ecmeta . 相似文献
992.
Research among adolescent samples has consistently demonstrated that a hopeful mindset is associated with resilience and global well-being. Further, research suggests that hope is influenced from an early age from connections with supportive caregivers. However, because older youth in the child welfare system may lack supportive caregivers, alternative sources of hope may be needed. To test a theory that supportive child welfare caseworkers can serve as external sources of hope, we conducted a cross-sectional study of youth in the child welfare system from a single state (N = 149). Using surveys with established scales to measure the variables of interest, the study tested a structural equation model of (1) youth's external hope in their caseworker as a driver of (2) internal hope in themselves leading to (3) more positive perceptions of academic success. Perceptions of academic success were chosen as the final consequence of the model because academic success has been linked to many other variables of well-being across the lifespan. The results indicate that the proposed structural model fits the data well (χ2 = 327.9, df = 150; P < 0.001; root-mean-square error of approximation [RMSEA] = 0.09 [90% confidence interval – CI: 0.076, 0.103]; comparative fit index [CFI]: 0.920; standardized root-mean-square residual [SRMR]: 0.05). The results indicate that youths' hope in themselves had origins in external hope in the caseworker. Moreover, the final consequence was an increase in perceptions of academic success. Such results have implications by revealing how case management services can positively influence foster youths' hope and thereby influence their academic success. 相似文献
993.
994.
A comparison of evolutionary and environmental theories of erotic response part II: Empirical arenas
Evidence from studies of ethnic differences in sexual conservativeness and Papanicolaou (Pap) testing behaviors suggests that there may be culture-linked differences in rates of participation in physically invasive sexuality studies, resulting in volunteer bias. The effects of ethnicity and acculturation on participation in female psychophysiological sexual arousal research were investigated in a sample of Euro-Canadian (n = 50) and East Asian (n = 58) women. Participants completed a battery of questionnaires and were given either course credits or $10 for their participation. Participants were then informed about the opportunity to participate in a second phase of the study, which involved psychophysiological sexual arousal testing and which was completely optional. Contrary to expectations, the results showed that the East Asian women were more likely to participate in Phase 2 than the Euro-Canadian women. Among the East Asian women, greater heritage acculturation and lower mainstream acculturation predicted a lower likelihood of Phase 2 participation. The findings suggest the need to be wary of overgeneralizing female psychophysiological sexual arousal research results and may have implications for improving Pap testing behaviors in East Asian women. 相似文献
995.
Abstract The most important issue which surrounds attitude theory today is the so called “consistency issue.” It is an issue which focuses on the failure of attitude theory and research to demonstrate the kind of causal relationship between attitudes and behavior which has been traditionally asserted in the logical underpinnings of that theory. For some time, the critics of attitude theory and research have suggested that the inconsistency between attitudes and acts would not be reduced until attitudes were rooted in the social process within which human behavior occurs. This criticism has been responded to by contemporary attitude specialists who have made notable modifications in theory and research to take account of social variables which influence the assumed relationship between attitudes and behavior. However, some of the criticisms of attitude theory have gone beyond pointing out the lack of a “socialized” conception of the problem to attack the logical underpinnings of the entire enterprise. While this paper is not a renewal of these criticisms of attitude theory, it is an attempt to identify and explicate a conception of attitudes which is a true sociological alternative to more traditional psychological conceptions. 相似文献
996.
In three studies, we developed and validated a self‐report measure of women's sexual working models. In a pilot study we created an initial version of the Women's Sexual Working Models Scale (WSWMS), administered it to an exploratory sample of 470 women, and identified its 5‐factor structure. Study 1 confirmed the 5‐factor structure in a new sample: (1) Fostering commitment; (2) Evaluating a sexual partner's suitability; (3) Promoting frequent sexual activity through positive affect; (4) Restricting sexuality through shamefulness; and (5) Negative emotions that signal incompatibility with relationship goals. In Study 2, 444 Israeli women completed the WSWMS. Confirmatory factor analysis provided cross‐national evidence for the generalizability of the underlying factor structure of the WSWMS. 相似文献
997.
998.
Richard T. Lapan Amanda M. Marcotte Robert Storey Patricia Carbone Sharon Loehr‐Lapan Donna Guerin Teisha Thomas Deidre Cuffee‐Grey Aria Coburn Teresa Pfeiffer Latoya Wilson Stephen Mahoney 《The Career development quarterly》2016,64(2):126-139
An approach is presented for strengthening middle school standards‐based English language arts (ELA) classroom instruction by infusing theory‐ and research‐supported career development constructs and practices. Over an 8‐week period, 90 urban 7th graders participated in an integrated ELA–career development curriculum. Career agency emerged as an important construct for students. It was related to key markers of ELA achievement (i.e., standardized test scores, grades, and positive change in 6th‐ to 7th‐grade test scores) and elaborated on in nuanced ways by students in their written narratives. Four themes related to career agency were identified in student writings: time perspective, challenges of self‐direction, career development, and social and emotional development. Advantages for students and schools related to synergy, scale, and sustainability are discussed. 相似文献
999.
The purpose of this study was to provide an initial investigation into the work–family conflict (WFC) experiences of individuals who hold a second job. Specifically, we proposed two opposing theoretical arguments regarding the relationship between WFC and four measures of well-being: life satisfaction, physical health, emotional exhaustion, and exercise for individuals who hold two jobs. In a sample of individuals working two jobs, we tested whether the effects of WFC arising from the first job and from the second job exerted an additive or interactive effect on employee well-being. Our results indicated that for emotional exhaustion, physical symptoms, and life satisfaction, the effects of WFC from two jobs are interactive; but that for exercise, the effects of WFC from two jobs are additive. In both cases, the additional WFC experienced as a result of working a second job contributed to the prediction of employee well-being over and above WFC from the first job. Results are discussed within the context of relevant theory, and suggestions are made for future research. 相似文献
1000.
Lillian T. Eby Melissa E. Mitchell Cavan J. Gray Laura Provolt Anna Lorys Erica Fortune 《Community, Work & Family》2016,19(5):604-620
This study uses content analysis to provide a qualitative exploration of how life roles are affected by frequent (i.e. at least weekly) gambling, based on in-depth interviews with a community sample of 161 non-treatment-seeking frequent gamblers. Over half (51.6%) of the participants indicated problems associated with gambling and 131 examples were identified. The majority of problems were relational (50.4%), followed by financial (19.8%), work (13.7%), and school related (8.4%). Slightly less than half of participants (41.7%) reported losses due to gambling and 92 examples were provided. The most frequently reported loss was identity related (54.3%), which included self-esteem/shame (38.0%), estrangement from family (34.0%), estrangement from friends (16.0%), and estrangement from work colleagues (6.0%). Additional losses included health (29.3%) and financial (8.7%). Almost two-thirds of participants (64.6%) reported difficulty concentrating in family (18.4%), work (16.8%), and school (9.6%) activities, whereas general concentration problems comprised an additional 48.8% of the examples provided. Half of participants (49.1%) discussed behavioral withdrawal due to gambling, which included withdrawal from work (44.3%), relationships (24.5%), school (15.1%), and personal (6.6%) activities. These findings paint a complex picture of how gambling interferes with different life roles for some frequent gamblers, identifying important areas for future research and practice. 相似文献