## Signal, noise, chance and chancers

For those who hold to personalised medicine as the future of therapeutics, the case is made that it’s about identifying the ones who will gain from the ones who don’t. Separating the signal from the background noise. If we did a randomised trial of ‘antibiotics for fever’ we may come away believing they had no […]

## Spirals of re-validation

In the UK, revalidation, to the eyes of anyone in a permanent post, brings thoughts of GMC pleasing e-paperwork and the joy of yet more hours staring at a barely functional system to prove you are safe and sensible enough to not play with computers but auscultate bunnies (where necessary) and diagnose life-threatening disorders. To […]

## MiniStatsBlog: Making decisions from numbers

It’s a thing we like to do in medicine – make decisions on the basis of numbers. The temperature is greater than 38C in a neutropenic child? Start antibiotics. The CRP in your snuggly neonate has reduced? Stop antibiotics. The PEWS score is high – review. Lots of researchers want to help out with this too, […]

## StatsMiniBlog: Pants and primary schools.

I’ve been struggling to get the concept behind random-effects meta-analysis out for some time – it’s the ‘average effectiveness’ in an ‘average population’ – with the prediction interval being the ‘actual width of where the truth might lie’. But .. yes .. but what does that actually mean & why does that matter? Well. Take a […]

## StatsMiniBlog: Path analysis

It’s been a while since a little burst of statistical fun hit the blogosphere but summer is sort of here, and you may be faced with a choice of tracks in a forest and unsure which one to take … Path analysis will not aid you. Path analysis (aka ‘structural equation modelling’ … sort of …) […]

## StatsMiniBlog: Middling differences

Is there a difference between these two non-parametric groups? (For example, the duration of cough after bronchiolitis…)     Time to cough resolution (days)    Rx A: Median 15 days  Rx B: Median 15 days You’d want to see a stats test though, wouldn’t you. […]

## StatsMiniBlog: Trial Sequential Analysis

You might have seen this “Trial Sequential Analysis” in the odd systematic review or meta-analysis, and seen some strange graphs with ‘cumulative z-score boundaries’ in them. And then either quickly closed the PDF or flicked away to catch up with an episode of Peppa Pig. But fear not. TSA is not as strange an idea […]

## StatsMiniBlog: Value of Information

When there’s a limited pot of money to do research with, it would be sensible to put it where it might do the most good, wouldn’t it? Well that’s exactly what the ‘value of information’ framework attempts to help researchers / commissioners of research do … The concept is to take what you already know, with […]

## StatsMiniBlog: Factor Analysis

It’s another one of those things that you’ll see in a paper, often followed by the word “eigenvalue” and shudder, perhaps externally as well as internally. The’ll be a follow-up of ‘structure’ or the like after that, often fancifully named as different domains. The easiest (!) way to think of how it works is to […]

## StatsMiniBlog: Rasch Analysis

Yes. You’re right. I have spelt ‘rash’ wrongly and yes, there are many very very bad puns which can come from this title. But you may have seen, occasionally, Rasch analysis as a thing on scientific paper and wondered ‘Why have they spelled rash wrong?’ Rasch analysis is a way of creating a properly scaled measurement from […]