Acceptability of a Mobile Clinical Decision Tool Among Emergency Department Clinicians: Development and Evaluation of The Ottawa Rules App.

Background: The Ottawa Ankle Rules, Ottawa Knee Rule, and Canadian C-Spine Rule-together known as The Ottawa Rules-are a set of internationally validated clinical decision rules developed to decrease unnecessary diagnostic imaging in the emergency department. In this study, we sought to develop and evaluate the use of a mobile app version of The Ottawa Rules.

Objective: The primary objective of this study was to determine acceptability of The Ottawa Rules app among emergency department clinicians.

Association of skirt size and postmenopausal breast cancer risk in older women: a cohort study within the UK Collaborative Trial of Ovarian Cancer Screening (UKCTOCS).

Objectives: Several studies suggest that overall and central-obesity are associated with increased breast cancer (BC) risk in postmenopausal-women. However, there are no studies investigating changes of central obesity and BC. We report on the association of BC risk with self-reported skirt size (SS; waist-circumference proxy) changes between 20s and postmenopausal-age.

Identifying hopelessness in population research: a validation study of two brief measures of hopelessness.

Objective: Hopelessness is an important construct in psychosocial epidemiology, but there is great pressure on the length of questionnaire measures in large-scale population and clinical studies. We examined the validity and test-retest reliability of two brief measures of hopelessness, an existing negatively worded two-item measure of hopelessness (Brief-H-Neg) and a positively worded version of the same instrument (Brief-H-Pos).

Design: Cohort study.

Gene tree distributions under the coalescent process.

Under the coalescent model for population divergence, lineage sorting can cause considerable variability in gene trees generated from any given species tree. In this paper, we derive a method for computing the distribution of gene tree topologies given a bifurcating species tree for trees with an arbitrary number of taxa in the case that there is one gene sampled per species. Applications for gene tree distributions include determining exact probabilities of topological equivalence between gene trees and species trees and inferring species trees from multiple datasets.

A comparison of methods for estimating the transition:transversion ratio from DNA sequences.

Estimation of the ratio of the rates of transitions to transversions (TI:TV ratio) for a collection of aligned nucleotide sequences is important because it provides insight into the process of molecular evolution and because such estimates may be used to further model the evolutionary process for the sequences under consideration. In this paper, we compare several methods for estimating the TI:TV ratio, including the pairwise method [TREE 11 (1996) 158], a modification of the pairwise method due to Ina [J. Mol.

A statistical framework for combining and interpreting proteomic datasets.

Motivation: To identify accurately protein function on a proteome-wide scale requires integrating data within and between high-throughput experiments. High-throughput proteomic datasets often have high rates of errors and thus yield incomplete and contradictory information. In this study, we develop a simple statistical framework using Bayes' law to interpret such data and combine information from different high-throughput experiments.

Variation among natural isolates of Neurospora on small spatial scales.

Although species of Neurospora are among the most studied model organisms in genetics and biochemistry, basic questions remain with respect to their ecology and population biology. In this study, we sought to clarify relationships among individuals over a small spatial scale, toward assessing both local variation and mode of colonization. Isolates of Neurospora were collected after fires in the Florida Everglades (May 1999), where abundant colonies appeared on diverse plants, including grasses and woody shrubs.

Estimation of evolutionary parameters with phylogenetic trees.

An important issue in the phylogenetic analysis of nucleotide sequence data using the maximum likelihood (ML) method is the underlying evolutionary model employed. We consider the problem of simultaneously estimating the tree topology and the parameters in the underlying substitution model and of obtaining estimates of the standard errors of these parameter estimates. Given a fixed tree topology and corresponding set of branch lengths, the ML estimates of standard evolutionary model parameters are asymptotically efficient, in the sense that their joint distribution is asymptotically normal with the variance-covariance matrix given by the inverse of the Fisher information matrix.

The optimal number of donor biopsy sites to evaluate liver histology for transplantation.

Macrovesicular steatosis (MaS), fibrosis, and inflammation have been associated with poor graft function after liver transplantation. We evaluated histological variation in livers to determine the optimal number of biopsies to estimate pathological characteristics in livers for transplantation. Specimens from autopsies performed during 3 months in 16- to 70-years-olds without known liver disease or drug and/or alcohol abuse were examined.