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1.
J Plast Reconstr Aesthet Surg ; 91: 399-406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461624

RESUMO

BACKGROUND: Reporting bias refers to the phenomenon in which the reporting of research findings is influenced by the nature of the results. Without the totality of evidence, clinical practice may be misguided. The objective of this work was to examine the extent of reporting bias in clinical trials of breast reconstruction surgery. METHODS: We searched and extracted data from all completed breast reconstruction clinical trials published in ClinicalTrials.gov from database inception to August 2020. Investigators sought to identify published full manuscripts of the registered trials. The primary outcome was classified as positive or nonpositive and trials were classified as industry or nonindustry funded. Time to publication in a peer-reviewed journal was computed and compared using time-to-event analysis. Trial characteristics associated with publication were evaluated using logistic regression. RESULTS: A total of 156 clinical trials were identified, of which, 53 trials were published. The median time to publication was 22 months (IQR, 13-35 months). Industry-funded studies were associated with a longer time to publication (HR = 2.4, p = 0.023) and publication in lower-impact journals (OR = 3.7, p = 0.048). Randomized clinical trials were associated with faster times to publication than nonrandomized studies (aHR = 3.2, p = 0.030). Statistical significance and the effect size were not associated with time to publication. CONCLUSIONS: We found no evidence that industry-funded trials were more likely to report a positive primary outcome. However, industry-funded trials were associated with a longer time to publication and publication in lower-impact journals.


Assuntos
Modelos Logísticos , Humanos , Bases de Dados Factuais , Ensaios Clínicos como Assunto
2.
J Org Chem ; 76(11): 4392-5, 2011 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-21545125

RESUMO

Sulfur-, selenium-, and nitrogen-containing compounds bearing leaving groups in the ß-position undergo facile substitution chemistry enabled by anchimeric assistance. Here we provide direct comparisons between such systems in the rigid bicyclo[3.3.1]nonane framework easily derived from 1,5-cyclooctadiene. For a series of dichloride electrophiles of this type, the relative reactivities were found to be Se ≫ (alkyl)N > S ≥ (propargyl)N > (phenyl)N, with the reaction rates at the two extremes differing by more than 3 orders of magnitude. For the N-alkyl case, substitution rates were largely independent of the trapping nucleophile but were strongly dependent on solvent, showing that the process is controlled by the formation of the high-energy three-membered cationic intermediate.


Assuntos
Alcanos/química , Compostos Aza/química , Cicloparafinas/química , Selênio/química , Enxofre/química
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