Article Text

Towards evidence based medicine for paediatricians
    1. Correspondence to Dr Bob Phillips, Centre for Reviews and Dissemination, University of York, York YO10 5DD, UK; bob.phillips{at}

    Statistics from

    Getting it straight from the start

    For  more than a decade Archimedes has presented clinical queries and appraised the evidence that emerges, leading on to a clinical conclusion to the dilemma. What is strikingly common is that many questions can start in a muddle, and a failure to get an ‘evidence-based answer’ might actually be a failure to ask an accurate question.

    In a recent trans-disciplinary teaching session, one anaesthetist summarised the formulation of evidence-based medicine (EBM) questions as ‘Does drug A compared to drug B make outcome X happen more or less in patient group Z?’—a brilliant anagram of the ‘PICO’ formula into Intervention, Comparator, Outcome, Patients. Now if your question doesn't fit, or can be fudged to fit, this, then you need to unpack it.

    Is it a diagnostic test? Try ‘Does super-TB-detector kit compared with Proper Microbiological Stuff indicate the presence of Mycobacterium tuberculosis infection in patients with proper immune systems?’. Prognostic features? ‘Does the presence of clinical choroamnionitis make it more likely that necrotising enterocolitis will occur in this premature neonate?’.

    Complex questions, such as ‘What’s the best diagnostic test for leukaemia?’, can drive you either to textbook style review articles, whose statements you can then EBM-ise, or allow you to list a series of sub-questions (Full blood count? Film? Six-colour flow cytometry?). Others, such as ‘Should I do a CT before lumbar  puncture in teenagers?’, might collapse into a series of queries (How effective are the clinical features of raised intracranial pressure in teenagers/adults?) which might stop you needing to ask “how good is CT at ruling out raised intracranial pressure?”

    Now if you get your PICO (or ICOP) straight from the start, you'll be well on the way to finding evidence-based answers to the evidence-based question you’ve decided upon.

    View Abstract


    • Competing interests None.

    • Provenance and peer review Commissioned; externally peer reviewed.

    Request permissions

    If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

    Linked Articles