BACKGROUND Treatment benefits and harms are often communicated as relative risk reductions and increases, which are frequently misunderstood by doctors and patients. One suggestion for improving understanding of such risk information is to also communicate the baseline risk. We investigated 1) whether the presentation format of the baseline risk influences understanding of relative risk changes...

OBJECTIVES This study was conducted to investigate the relationship between heat-related illnesses developed in the summer of 2012 and temperature. METHODS The study analyzed data generated by a heat wave surveillance system operated by the Korea Centers for Disease Control and Prevention during the summer of 2012. The daily maximum temperature, average temperature, and maximum heat index wer...

This article examines the legal and ethical issues that surround the confidentiality of medical records, particularly in relation to patients who are HIV positive. It records some historical background of the HIV epidemic, and considers the relative risks of transmission of HIV from individual to individual. It explains the law as it pertains to confidentiality, and reports the professional gui...

INTRODUCTION Recent studies have indicated higher risk of fractures among coffee drinkers. To quantitatively assess the association between coffee consumption and the risk of fractures, we conducted this meta-analysis. MATERIAL AND METHODS We searched MEDLINE and EMBASE for prospective studies reporting the risk of fractures with coffee consumption. Quality of included studies was assessed wi...

Modified Poisson regression, which combines a log Poisson regression model with robust variance estimation, is a useful alternative to log binomial regression for estimating relative risks. Previous studies have shown both analytically and by simulation that modified Poisson regression is appropriate for independent prospective data. This method is often applied to clustered prospective data, d...

BACKGROUND Disadvantages have already been pointed out on the use of odds ratio (OR) as a measure of association for designs such as cohort and cross sectional studies, for which relative risk (RR) or prevalence ratio (PR) are preferable. The model that directly estimates RR or PR and correctly specifies the distribution of the outcome as binomial is the log-binomial model, however, convergence...

To increase change between groups, randomised clinical trials (RCT) often include patients with high risk for a particular outcome, by inclusion criteria that select predictors for that outcome. This increases the statistical power, and fewer patients are required for that RCT. The way in which patient selection influences the power, and thus sample size required, depends on how an intervention...

Both the odds ratio and the relative risk compare the relative likelihood of an event occurring between two groups. The relative risk is easier to interpret and is consistent with general intuition. Some designs, however, allow only for the calculation of the odds ration. Covariate adjustment is easier for an odds ratio. Finally, the odds ratio avoids ambiguity by being invariant to lthe labeli...

BACKGROUND AND PURPOSE External validation of the Framingham stroke risk function has been rarely performed. We assessed its predictive ability in a population-based cohort of French elderly. METHODS The sample comprised 6913 subjects from the 3C Study, aged 65 to 84 at baseline, who were followed up to 6 years. Predictive accuracy of the original Framingham stroke risk function was assessed ...