Tarnished gold

What can you do when a ‘gold standard’ isn’t actually that good at diagnosing a condition? It can be terribly problematic in interpreting sensitivity and specificity – for example comparing polymerase chain reaction diagnosis of microbiological infection with culture results. The ‘false positive’ may actually reflect real, and otherwise missed, diagnosis, and the ‘false negatives’ […]

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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 […]

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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 […]

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Diagnostic tests: as easy as I, II, III

Diagnostic testing keeps coming back to bite Archi, and that’s not just because of a probability-based failure about a small relative and a missed diagnosis of congenital heart disease. No, the problem with diagnostic tests and their use and abuse remains difficult because the methods of research, the quality of research and the consequence of […]

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