PURPOSE We evaluated the effect of positive superficial and/or deep margin status on local recurrence (LR) in invasive breast cancer treated with breast-conserving surgery (BCS) followed by radiotherapy. MATERIALS AND METHODS In total, 3,403 stage 1 and 2 invasive breast cancer patients treated with BCS followed by radiotherapy from January 2000 to December 2008 were included in this study. T...

To investigate how cell type proportions are regulated during Dictyostelium development, we have attempted to find out which cell type produces DIF-1, a diffusible signal molecule inducing the differentiation of prestalk-O cells. DIF-1 is a chlorinated alkyl phenone that is synthesized from a C12 polyketide precursor by chlorination and methylation, with the final step catalysed by the dmtA met...

background & objective: autoimmune bullous diseases are associated with autoimmunity against structural components in the skin and mucous membranes. autoantibodies are against the intercellular junctions in pemphigus disease and hemidesmosomal unchoring complex in pemphigiod diseases and epidermolysis bullosa aquisita. the tissue-bound and circulating serum autoantibodies can be detected wi...

in the previous two parts of educational manuscript series in emergency, we explained some screening characteristics of diagnostic tests including accuracy, sensitivity, specificity, and positive and negative predictive values. in the 3rd  part we aimed to explain positive and negative likelihood ratio (lr) as one of the most reliable performance measures of a diagnostic test. to better underst...

Let Y be generated from ∼N(μ υ2), where μ= √ e2·lr−1+υ − υ2, where lr ∈ {x ∈ R : e2·lr−1+υ − υ2 ≥ 0}. Under DGPs of this form, E[Λi(φ∗)] = lr . Thus, varying lr controls how far the deviation is from H0. On the other hand, when lr = 0, varying the parameter υ2 controls how large ω2 is. Setting υ2 = 1 makes ω2 = 0, and setting υ2 far from 1 makes ω2 large. First, I fix lr = 0 and study the null ...

As part of test score validity, differential item functioning (DIF) is a quantitative characteristic used to evaluate potential item bias. In applications where a small number of examinees take a test, statistical power of DIF detection methods may be affected. Researchers have proposed modifications to DIF detection methods to account for small focal group examinee sizes for the case when item...

This article presents a meta-analysis of studies investigating the effectiveness of the Mantel-Haenszel (MH) procedure when used to detect differential item functioning (DIF). Studies were located electronically in the main databases, representing the codification of 3,774 different simulation conditions, 1,865 related to Type I error and 1,909 to statistical power. The homogeneity of effect-si...

BACKGROUND Effect size reporting and interpreting practices have been extensively recommended in academic journals when analyzing primary outcomes of all empirical studies. Accordingly, the sample squared multiple correlation coefficient is the commonly reported strength of association index in practical applications of multiple linear regression. METHOD This paper examines the sample size pr...