In order to test a new treatment, in a standard randomised controlled trial, we are ethically assumed to have ‘equipoise’: an honest uncertainty at the same chance of a patient being allocated to the new or old treatment. But, I hear you scoff, how can any investigator put themselves through the hell of ethical administration […]
Secrets and lies. Truth and beauty.
… and other Bohemian aphorisms … There is a quite brilliant paper from the under-advertised PLoS One which shows how, in the are of incubation periods for respiratory disease, Truth By Citation is quite strikingly different than the reality of the evidence. The networks of citations demonstrate how repetition, sometime but not always with a […]
Confident in predicting? Meta analysis models step two.
So, in a previous post I made a foray into the dangerous world of statistical models of meta-analysis. Now, I’ll try hard to explain why we need to start doubting random effects meta-analysis more than we often have done. […]
It’s how mixed up? Meta analysis models step one.
Well, I have to start with an apology. In one of these columns, I foolishly claimed that the difference between a Peto OR fixed effect meta-analysis and a DerSimonian-Laird random effects meta-analysis was pointlessly academic. It’s not. Now, this might start getting all statistical, but there is a clear and important difference. Meta-analysis comes in […]
Many outcomes give no answer?
Some systematic reviews are confusing. Sometimes this is just poor writing style. Sometimes it’s because the techniques are difficult to grasp (meta-analytic item-response analysis, anyone?) And occasionally it’s because the data don’t seem to add up ‘right’. […]
I’m fairly sure you’ll remember the RAMbo method of reviewing the validity of single randomised controlled trials. And so I think that many readers will have been having sleepless afternoons, struggling through the lengths of a ‘User’s Guide’ checklist for systematic reviews thinking “Which action hero can rescue me from this mire?”. Or perhaps not. […]
Finding the question
It’s one of the tenets of the evidence-based practice process that questions are framed as ‘PICO’: patient, intervention, comparison and outcome. But what happens when the question is bigger than PICO? […]
New things in evidence synthesis
The days of a meta-analysis being the simple adding up of lots of studies, pretending that they are all just tiny pieces of the One Big Trial that was performed before the world was made are on their way out. Newer ways of using synthesised evidence – like meta-regression and individual patient data analysis – […]