The log-rank test has been widely used to test treatment effects under the Cox model for censored time-to-event outcomes, though it may lose power substantially when the model's proportional hazards assumption does not hold. In this article, we consider an extended Cox model that uses B-splines or smoothing splines to model a time-varying treatment effect and propose score test statistics for t...

Study results on the association of positive affect with survival are conflicting. This disagreement potentially arises from poor control for health or negative affect and for the various age groups studied. The authors examined if positive affect predicts survival; whether this association is preserved after controlling for negative affect, socioeconomic status, lifestyle, and health; and whet...

BACKGROUND Self-rated health (SRH) has strong predictive value for mortality in different contexts and cultures, but there is inconsistent evidence on ethnoracial disparities in SRH in Latin America, possibly due to the complexity surrounding ethnoracial self-classification. MATERIALS/METHODS We used 370,539 Single Nucleotide Polymorphisms (SNPs) to examine the association between individual ...

BACKGROUND Functional dependency, the need for help in basic activities of daily living, is an important patient-oriented outcome. We aimed to describe the development of dependency in Parkinson's disease (PD) and identify independent prognostic factors for this outcome. METHODS We analyzed data from the Parkinsonism Incidence in North-East Scotland (PINE) study, a prospective, community-base...

Iberian x Meishan F2 piglet's preweaning survivability was analyzed using categorical data regression procedures within the proportional hazards assumption. A frailty sire model was assumed with the litter effect treated as an additional random source of variation. Moreover, the relative birth weight within litter and the litter effect were considered time-dependent covariates that changed thei...

BACKGROUND Controversy persists regarding the correct strategy for bifurcation lesions. Therefore, we combined the patient-level data from 2 large trials with similar methodology: the NORDIC Bifurcation Study (NORDIC I) and the British Bifurcation Coronary Study (BBC ONE). METHODS AND RESULTS Both randomized trials compared simple (provisional T-stenting) versus complex techniques, using drug...

BACKGROUND Recurrent tuberculosis suggests potentially modifiable gaps in tuberculosis treatment and control activities. The frequency of late recurrences following treatment completion has not been well-studied. We determined the frequency of, and risk factors associated with, tuberculosis that recurs at least one year after completion of anti-tuberculosis therapy in California. METHODS The ...

OBJECTIVE To determine the cardiovascular benefits of atorvastatin stratified by blood pressure-lowering regimen, 2.2 years after closure of the lipid-lowering arm (LLA) of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT-LLA). METHODS In ASCOT-LLA, 10,305 hypertensive patients randomized to amlodipine-based or atenolol-based therapy and with a total cholesterol 6.5 mmol/l or less were fu...

Allogeneic hematopoietic cell transplantation is widely used to treat adults with high-risk acute lymphoblastic leukemia. The aim of this study was to analyze whether the results changed over time and to identify prognostic factors. Adult patients treated between 1993 and 2012 with myeloablative allogeneic hematopoietic cell transplantation from HLA matched sibling (n=2681) or unrelated (n=2178...

BACKGROUND AND OBJECTIVES The Initiating Dialysis Early and Late study showed that planned early or late initiation of dialysis, based on the Cockcroft and Gault estimation of GFR, was associated with identical clinical outcomes. This study examined the association of all-cause mortality with estimated GFR at dialysis commencement, which was determined using multiple formulas. DESIGN, SETTING...