Evidence-based medicine: How it becomes a 4-letter word

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Original Research

Evidence-based medicine: How it becomes a 4-letter word

J Fam Pract. 2005 July;54(7):604-606

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References

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Second, while attitudes and practice beliefs can be used to weigh elements of evidence to reach a final conclusion, the conclusion should not negate other perspectives. An important skill of an adept clinician is the ability to interweave the healthcare provider’s and the patient’s attitudes and practice beliefs into the body of existing evidence to determine the appropriate intervention.¹³ However, attitudes and practice beliefs vary from individual to individual and from community to community. When these factors play a critical role in defining the appropriate action based on the evidence, how attitudes and practice beliefs are used should be explicitly stated. In the Pap smear example, the pivotal issue of contention was the belief about whether individual practitioners should act as stewards of limited healthcare resources. Proponents of using solely the liquid-based Pap smear felt the cost problem was a national issue and that the actions of the individual clinician had little impact on global healthcare costs. Others felt their local actions affected insurance premiums, leading directly to decreased healthcare access.¹¹ For cervical cancer, the key impact on mortality is getting any form of screening.¹ Using the liquid-based method for low-risk women may increase cervical cancer mortality by increasing costs and decreasing healthcare access. Removing conventional Pap smears disempowered the latter group of clinicians from implementing their practice beliefs and attitudes.

FAST TRACK

Inconclusive evidence should not be stated in absolute terms; it is more helpful to explicitly state the limits of what we know

Finally, a conclusion should not be labeled as “evidence-based” when it is really made on other grounds such as economics, law, ethics, convenience, social values, or policy. Certainly, reviewing medical evidence is an important step in making decisions. However, the process for making decisions on these factors should be held to the same standards as making medical evidence decisions. This includes defining the process and explicitly stating the basis by which final decision will be made. The US is very conflicted when it comes to dealing with these non-evidence issues. We have no national standard for incorporating costs into healthcare decisions.^14,15 With respect to healthcare delivery, we have a wide range of social values that are sometimes disproportionate to logical expectations.¹⁶ Few effective systems are in place to incorporate these elements in healthcare decisions and, as a result, “evidence” is often used as a code word to focus on other issues.

For the Pap smear example, the decision factors were really economics, law, and systems of care. Proponents of the liquid-based method cited the community standard of care, fear of malpractice, patient expectations of receiving the latest technology, and the ease of adopting one screening method for the entire office. Others felt these issues, although important, were secondary to the lack of evidence supporting a liquid-based system as a sole screening method. For lowrisk women, adopting the liquid-based method only makes economic sense if screening is done every 2 or 3 years.¹⁷ However, many low-risk women still favor performing a Pap smear annually.¹⁸ As a result a decision-making process other than the strict EBM method, focusing on other factors would be necessary to change the practice standard.

FAST TRACK

Making a decision under the rubric of EBM, when other variables are clearly playing a role, perpetuates the perception of its limited utility

Conclusions: Recognize the limitations of EBM

Cervical cancer screening serves as a common example of a difficult decision healthcare providers are faced with on a daily basis—what to do when evidence, based on patient oriented outcomes, is inconclusive. Providers do not have the luxury of merely stating the evidence is inconclusive; they must act. Frequently decisions are based on attitudes and practice beliefs in a broader context of unique economic, legal, and practice environments.

EBM is one tool in the decision-making armamentarium. It is a very powerful tool and has had a very positive impact on healthcare. Its methods have been well defined and explicitly stated. However, failing to recognize its limitations and making a decision under the rubric of EBM, when other variables are clearly playing a role, perpetuates the perception of its limited utility. Advocates of EBM need to wield this instrument carefully and judiciously.

CORRESPONDENCE
Alex Krist, MD, 3825 Charles Stewart Drive, Fairfax VA 22033. E-mail: ahkrist@vcu.edu