The team writing this study reviewed the decisions of forensic physicians who were determining if the age of adolescents involved in French judicial proceedings for criminal or asylum purposes, looking to see if their decisions were supported by the best quality evidence. The key finding - that they often were not - seemed to frequently centre on the average.

Let me explain. If a wrist X-ray gives a skeletal age of 8 years 2 months … this isn’t true. It’s the average age of the folk who were x-rayed to make up the atlas. Some might have been 7 years, others 9 years 10 months. The ‘truth’ is most likely to be about 8yr 2m, but may be wildly different. The spread of ages is captured with the standard deviation, and about 95% of the ages will be within 2 standard deviations of the mean.

This is even more obvious if you take another example: the classroom. The ‘average’ mark might be 65%, but it won’t shock most to find that some pupils would score 40% and others 100%. The ‘true’ mark isn’t 65% - obviously.

So say you take a wrist X-ray, check for 3rd molars, and the average comes out at 18 years 3 months. The standard deviation might also tell you, within 95% certainty,  that the adolescent may be 15yrs 11 mth old. Is refusing asylum to this - potential - child then a human rights abuse because of a failure to understand statistics?

What is the value of such a finding, and what should it prompt the paediatrician and obstetrician to do for the baby, before or after birth? Fortunately for Archi, a team from North Middlesex (UK) are trying to answer for us. But is there any experience of different approaches out there?

What may at first seema great idea (tighter trunk muscles with a flexible corset) soon turns to lavartorial distress as their ease of disgorgement is not always as great as the more common cotton poppered vest.  And their cost is considerably more than a pack of three undershirts from George.  So is there enough evidence to ‘prescribe’ lycra clothing as a medical aid, like hernia supports and wigs for my big ‘uns on chemo?

as Dr Shah in Canada is undertaking an Archimedes reveiw to see if there is a really impressive benefit for glyerine in neonates by way of helping them feel or preventing jaundice.

Anyone currently using this approach?

Acknowledgement: Photo from Rob! under a CreativeCommons licence(Dog unnamed)

Well, it’s a new one on me, and one I find rather dubious. Good job there are folk who are looking at this with some interest; Drs Winkworth & Powell for Archimedes for starters. Anyone else any thoughts on the subject?

Acknowledgement: dimninkolov’s photo under a CreativeCommons licence

Jeremy Howick, Paul Glazsiou and Jeffrey Aronson have captured a concept that all practising EB paediatricians have used for some time, and set it solidly within an unassailable tradition of critical appraisal. They have revisited the Revised Bradford-Hill Guidelines (not criteria) for Causation and developed the parachutes of evidence: a trio of the main ‘chute (direct evidence), and two subsidiary ‘chutes (mechanistic and parallel evidence).

Direct Evidence is the stuff one you rely on most securely. This is when the RCT gives results, or an exceptionally effective intervention is impossibly better than all others (like when insulin was first used in DKA). Parallel Evidence is the stuff we use in paediatrics a lot: where similarities exist between the direct evidence in other populations and the ones we treat, and by replication of results across different areas. Mechanistic Evidence I still feel the shakiest relying on: coherence with other theories of how things work, and a plausible biological explanation.  The fear of finding out our theory of how illness and the body works is wrong - again - haunts me in the guise of the inability of bacteria to live in the acidic stomach, and the nightmare of SIDS caused by babies choking on their own vomit. There are times though, when we can use nothing else. (How else would you work out how to treat pancreatoblastoma, for example?)

This clear conceptualisation of how the various guises that evidence exists in can link to help us work out what works, what works best, and what’s likely to work for this patient goes even further to helping the practicioners of EBM assist those who don’t currently work within this framework to see it’s not all smoke, mirrors and NNTs.

Acknowledgement: o0bsessed, under a CreativeCommons 2.0 licence

There’s a feed of little messages (tweets) started about EBM, Archi and Paediatrics and we’ll see how it all goes. See twitter.com for more details on Twittering and http://twitter.com/archiadc to start to follow us.

2) how do we acquire and appraise evidence of adverse effects, or conjunctions of rare occurrences?

These questions are in the process of being assessed by Dr Boyes in Bradford, but thoughts (as always) are welcome.

What else would you like to see? A cite-u-like group for paediatricians interested in applying EBM? Some route to a posterous blog about questions as they are proposed? And are their clinical questions yet unanswered you’d like to have a crack at - or leave for someone else to do?

Use this thread to get going, or tweet away to @archiadc. We’ll see what we can do.

Acknowledgment: photo from Flickr by RyanMcD under a CreativeCommons2.0 license