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    Acquiring the clinical evidence

    Specificity in literature searching

    Boolean phrases help acquire the correct literature

    I became highly vested in the EBM literature during my second year as a professor for purposes of assessing resident/fellow/faculty/physician perceptions of EBM-based practice. I wanted to know how "knowledge gaps" were really experienced, could they be experienced, and what they did about it.  

    However, I was most interested in how they accessed clinical evidence at the point of care. Some said it was readily available at bed side and others said they had their assistants run their searches for them. Others said that they read at home or had new evidence emailed to them by predetermined groups of professionals packaging evidence.

    Chances are, you have many options available to you at your institution of higher learning or applied clinical practice. But most people just go straight to Google, Bing, or Yahoo to get some quick information. If this is your chosen method, then try to use Boolean operators in your quick searches to improve the specificity (finding quality evidence) of your search queries.

    1. When you put quotations, " " around words or a phrase, then only those words inside the quotations will be searched. And, because there are so many nebulous words in statistics, just type the word with parentheses. Ex: "Logarithmic transformation"

    When typing out a phrase or series of words in quotations, the search will follow the words in the exact order you typed them into the search engine. "how to string a guitar," or "nearest pizza place" are good examples. The search would yield specific sites and information on those two queries due to the quotations.

    2. The word, OR, requires that both terms in the search query appear in the webpage or document. Using OR broadens the search yield. It can also be used to link isomorphic, similar, and interdependent concepts.

    The search "statistics" OR "precision" OR "measurement" could lead to a vast number of resources linking the three constructs and can lead to new understanding of how the three interact. If you are researching an abstract construct or phenomena, the OR statement can pay vast dividends as you search the literature.

    3. The word, AND, is the default of the Boolean system and is used to separate other Boolean operators. With more use of AND, the search yield will decrease. It is used to amalgamate the different "parts" of the search query together.  
    The search "hotel" AND "arena" AND "paid parking," will give you a very specific search result related to close hotels with valet services that are close to the local sport arena.  

    4. The words, AND NOT, will exclude anything following it in the search query. It is a good phrase to use after you have performed a few searches and have seen the same redundant sites or information pop-up. Doing this eliminates the possibility for any of the query after AND NOT from being searched.

    5. Parentheses must be used with OR statements when there is another Boolean term in the search query.  

    For example: "hotel" AND "arena" AND (Marriott OR Hilton)

    This would find you a hotel close to the arena that was either Marriott or Hilton.  

    5. The truncation, *, is a powerful search tool that will include all forms of the parent word.

    For example: Isomorph* - isomorph, isomorphs, isomorphic, isomorphism, isomorphisms

    These simple Boolean operators, OR, AND, AND NOT, parentheses, and truncations can yield much more specific (identifying the correct information needed from search) search finding.
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    Evidence-based medicine and its applications

    Critical appraisal of the clinical evidence

    The cart before the horse

    I'm getting ready to add an Education section to the website, I decided to go back to first principles.  Bloom's Taxonomy had a pervasive impact on my philosophy of learning, teaching, and cognitive complexity.  I used it back in February of this year for an evidence-based medicine (EBM) presentation at work.  Bloom's Taxonomy* stipulated six levels of "knowing" or cognitive complexity.  The six levels in increasing order were knowledge, comprehension, application, analysis, synthesis, and evaluation.  

    Here is the conundrum that Bloom's Taxonomy exacts upon applied EBM practice:

    There are five steps to EBM:  Asking, acquiring, appraising, applying, and assessing.  

    With asking, the EBM literature posits that clinicians experience "cognitive dissonance" when they have a knowledge gap in their clinical practice.  In order to deter the dissonance, the clinician decides to ask a clinical question to fill that gap.

    With acquiring, the clinician uses the PICO (population, intervention, comparator, outcome) mnemonic to acquire the best clinical evidence, given the resources and time available.

    Now we get to critical appraisal of the literature.  When looking at the nomenclature of the word "appraisal," it is reflective of the highest level of "knowing" or cognitive complexity in Bloom's Taxonomy, evaluation.  EBM stipulates that clinicians must be able to critically appraise the methods and statistical analyses of published studies.  This means that clinicians have to have functioning at a very high cognitive level to do this correctly.

    However, past literature has shown that researchers feel anxious and intimidated by statistics due to a lack of experience and competency.**  Also, undergraduate and graduate medical training rarely equips clinicians with the necessary competencies to conduct and effectively interpret clinical research evidence.***

    So, how can your everyday clinician with limited empirical/statistical training who feels "cognitive dissonance" a second time in the five steps of EBM critically appraise the literature?  Therein lies the conundrum, in my opinion.  

    I'm positing that we need to refocus our efforts on the lower echelons of Bloom's Taxonomy by educating physicians, residents, fellows, faculty, pharmacists, nurses, and staff to better understand (knowledge), recognize (comprehension), choose (application), examine (analysis), and design (synthesis) research studies before we can expect them to critically appraise (evaluation) the literature.  
    *Bloom, B. S.; Engelhart, M. D.; Furst, E. J.; Hill, W. H.;Krathwohl, D. R. (1956). Taxonomy of educational objectives: The classification of educational goals. Handbook I: Cognitive domain. New York: David McKay Company.
    **Marquardt, DW.  Criteria for evaluating the performance of statistical consultants in industry.  The American Statistician 1981; 35; 216-219.
    ***Wegwarth O.  Statistical illiteracy in residents:  What they do not learn today will hurt their patients tomorrow.  Journal of Graduate Medical Education 2013; 5; 340-341.