Clinical trials are frequently analysed as if they were surveys when they are in fact experiments. In particular the experimental basis of clinical trials is rarely reflected in the graphs which are used to illustrate them. Proposals are made, and illustrated by example, as to how appropriate figure …

In this Perspective, George Davey Smith and colleagues outline how and why gene-environment equivalence, the fundamental principle of Mendelian Randomization (MR), must be properly applied and critica...

YouTube video by BBC Science Focus Magazine

•The calculation of simple ratios is ubiquitous in biomedical health research.•Ratios are formulated by dividing a numerator (Y) for a denominator (X) variable.•Ratios are spurious if underlying assum...

Professor George Davey Smith explains why he encourages scientists to look for ways they might be wrong.

Several times recently, in published papers and in papers I have been asked to review, I have come across the quite incorrect claim that the eligibility criteria of a clinical trial define the target ...

Is human energy expenditure constrained? This hypothesis was proposed by Herman Pontzer, and has received widespread interest with coverage from mainstream media, podcasts, and even the RI Christmas ...

Our editorial responsibility for the International Journal of Epidemiology (IJE) started at the dawn of the current millennium, and we marked the occasion

Observational studies often dance around the issue of causality. We propose guidelines to ensure that papers refer to whether or not the study aim is to investigate causality, and suggest language to ...

Background Following consumption of a meal, circulating glucose concentrations can rise and then fall briefly below the basal/fasting concentrations. This phenomenon is known as reactive hypoglycaemia...