It is also clear that EBM is not about cost cutting, although many hospital medicine programs were started with this as the primary goal, given the current healthcare environment. Certainly fears exist that EBM is being used by healthcare managers, organizations, and administrators as a cost-efficiency tool. It may be that good evidence is cost-efficient in certain situations, while in others it may require the healthcare system to invest more in itself if available evidence supports doing so. Thus it is imperative that hospitalists accept the challenge of incorporating EBM into their daily practice and become leaders in its application, with patient safety and quality of care as primary goals. If we don’t, others will define the role of EBM for us, with a potential for poor outcomes for the patient and the profession.
The EBM skill set and its tools are being continuously refined, with the evidence pyramid as one of the most basic principles (3). This evidence pyramid is a model for grading the evidence. It puts in perspective the different grades of evidence or study designs. For example, a systematic review of randomized controlled trials that show consistent results provides the highest quality evidence and is ranked accordingly in the pyramid. In contrast, a case report or case series of a treatment would be ranked much lower.
The first step in incorporating EBM into one’s daily practice requires an understanding of its analytical approach and access to the necessary tools. The process begins with asking a question that is answerable. A well-built clinical question is one that benefits the patient and clinician. Such questions are directly relevant to patient problems and phrased in ways that direct your search to relevant and precise answers.
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Figure 2. EBM queries can be constructed using the PICO method. This table was borrowed from the Centre for Evidence-Based Medicine web site: www.cebm.net.
In forming the question the following process, referred to as the PICO method, is helpful (4).
With the question formed, consider what type of question you have. This is often referred to as the typology of the question.
- Clinical Findings: Gathering and interpreting findings from the history, clinical examination, and test results.
- Etiology: Identifying causes for disease.
- Differential Diagnosis: Ranking by likelihood, seriousness, and treatability of the patients problem.
- Prognosis: Figuring out how to estimate the likely clinical course and complications over time of the disease
- Therapy: Selecting treatments to offer that do more good than harm and that are worth the effort and cost of using them.
- Prevention: Reducing the chance of disease by identifying and modifying risk factors and how to diagnose disease early by screening.
- Self-improvement: Keeping up-to-date, improve your clinical skills, and run a better, more efficient clinical practice.
The types of questions can next be matched to the type of research that may provide the answer:
- Diagnosis: prospective cohort study with good quality validation against “gold standard.”
- Prognosis: prospective cohort study.
- Therapy or prevention: prospective, randomized controlled clinical trial (RCT).
- Harm/Etiology: RCT, cohort or case-control study (probably retrospective).
- Economic: analysis of sensible costs against evidence-based outcome.
Once the question has been formed, the following steps lie ahead: finding the evidence, critically appraising the evidence, acting on the evidence, and, finally, evaluating one’s performance. Very much like the formation of the question, each of the subsequent steps involves an analytical approach that can be mastered. Technology—particularly personal computers, the Internet and PDAs—has made the task of mastering EBM easier in many ways. The additional steps in using EBM effectively will be addressed in future articles. A list of useful links is provided below.