A while ago Archimedes reviewed the benefits of using ‘pre-appraised’ search resources, short-cuts to the best methodological quality evidence to answer clinical questions. The favoured database of many, PubMed [www.pubmed.gov] has now receieved a new addition to the range of resources on offer. […]
Category: critical appraisal note
Slice, DICE and eventually something will happen
Did you know that aspirin following MI doesn’t work for those with Gemini and Libra star signs? No, it’s true*. The ISIS-2 trial, which demonstrated the mortality benefits for anti-platelet agents after myocardial infarction with a p<0.00001 only showed benefit for people born in ten of the twelve signs of the zodiac.So if you believe […]
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 […]
Hurtful or helpful?
When you’re thinking about applying the results of a clinical trial, its’ often difficult to get a meaningful handle on the balance that should be made between the beneficial and adverse effects of a treatment. If the medicine gives pain relief from your laparotomy to 1 extra patient in every three that take it (NNT=3), […]
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 […]
Natural frequencies “keeping it real”
So, on hearing Matthew Thompson open up a mini-session with natural frequencies my mind turned to the healing power of crystals, and I become acutely concerned that the open-minds approach of the Teaching EBM Conference had gone too far. But this was quashed quickly by his description: […]
Well, the world of EBM teaching has once more benefited from the bilingual brilliance of Amanda Burls [@ajburls for the Tweeterati], in a superb hour-long lecture at the 16th Oxford Conference on Teaching Evidence Based Medicine. Gardening and teaching are not too different, it seems. The role of the facilitator is to encourage growth of […]
Unknowns: known, unknown and uncertain
Along with Rumsfelt, the drug-addled Dr. House and everyone who’s ever sat an exam, we can all recollect times when we know that we don’t know something. And we have times when we know something. And we have times when we learn about something we didn’t know we were unaware of. (Varenicline anyone?) And we […]