BACKGROUND Cluster randomized controlled trials increasingly are used to evaluate health interventions where patients are nested within larger clusters such as practices, hospitals or communities. Patients within a cluster may be similar to each other relative to patients in other clusters on key variables; therefore, sample size calculations and analyses of results require special statistical ...

OBJECTIVE To appraise critically the relevance and value of the evidence base to promote and support the duration of breast-feeding, with a specific focus on disadvantaged groups. DESIGN A systematic review was conducted of intervention studies relevant to enhancing the duration of breast-feeding; topics included public health, public policy, clinical issues, and education, training and pract...

We perform a first-principles based computational analysis of the effect of particle size and support material on the electrocatalytic activity of platinum nanoparticles. Using a mechanism for oxygen reduction that accounts for electric field effects and stabilization from the water layer on the (111) and (100) facets, we show that the model used agrees well with linear sweep voltammetry and ro...

OBJECTIVE To assess the methodological quality of the design and reporting of randomized controlled trials published in one major dermatology specialty journal. DESIGN AND DATA SOURCES In a survey of all published parallel group randomized controlled trials, we found 73 reports with allocation described as randomized from all issues of Clinical and Experimental Dermatology from its inception ...

BACKGROUND This update describes changes to procedures for our randomised controlled trial of 'On Your Feet to Earn Your Seat', a habit-based intervention to reduce sedentary behaviour in older adults. Some of the amendments have arisen from the addition of new sites, each offering different possibilities and constraints for study procedures. Others have been made in response to problems encoun...

BACKGROUND This article corresponds to a literature review and analyze how heterogeneity of treatment (HTE) is reported and addressed in cohort studies and to evaluate the use of the different measures to HTE analysis. METHODS prospective cohort studies, in English language, measuring the effect of a treatment (pharmacological, interventional, or other) published among 119 core clinical journ...